What's it gonna take? 300hp from a 305?
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Car: 1987 Camaro Z28
Engine: 5.0, 305, V8, 4BBL
Transmission: 700R4
What's it gonna take? 300hp from a 305?
I have looked into doing some kind of engine work to my car. But I wasnt sure what to do. I have decided to keep the 305, rebuild it, and try to get more horses out of it, preferably 300. The engine needs to be rebuilt anyway, so why not do it right, and get more horses out of it?
The only thing is, I dont know where to start, what to buy, or what to change. I recently had the trans rebuilt. The rear is stock as far as I know. I was told that I could put 300 hundred horses out of the stock trans and rear without hurting them. Anybody got any imput???
The only thing is, I dont know where to start, what to buy, or what to change. I recently had the trans rebuilt. The rear is stock as far as I know. I was told that I could put 300 hundred horses out of the stock trans and rear without hurting them. Anybody got any imput???
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Car: 85 Trans Am
Engine: 350 (CCC QJet)
Transmission: 700R4
Axle/Gears: 3.08 9 bolt
well before the "350" people come in, maybe look into a 335 or so stroker kit, look in the magazines they are always there, of course all the basics of a rebuild. New, better valve train (Do It Once, Do It Right).
There are tons of things that can be searched on these forums too.
Good Luck
There are tons of things that can be searched on these forums too.
Good Luck
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Car: 82 Z28
Engine: Al LT1 headed LG4 305
Transmission: TH350
Axle/Gears: 3.73 posi with spacer
It will be cheaper to rebuild a 350, because the parts cost less.
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Car: 85 Trans Am
Engine: 350 (CCC QJet)
Transmission: 700R4
Axle/Gears: 3.08 9 bolt
Originally posted by ME Leigh
It will be cheaper to rebuild a 350, because the parts cost less.
It will be cheaper to rebuild a 350, because the parts cost less.
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Car: 1987 Camaro Z28
Engine: 5.0, 305, V8, 4BBL
Transmission: 700R4
But i have a 305, and thats what i have to use. If i had the money to do it better and buy a 350, i would. Getting it bored .30 wouldnt be a problem.
#7
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Here's a clue:
325 HP out of 305 CID
I've seen some members in this forum claim to reach higher than this number. Search the forum for "305" and "HP" and see what you get.
325 HP out of 305 CID
I've seen some members in this forum claim to reach higher than this number. Search the forum for "305" and "HP" and see what you get.
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Car: 85 firebird
Engine: Pos 2.8 pulled and replaced with a 350 tpi motor converted to carb.
Transmission: 700r4, vette servo,shift kit, hayden 15"x8" trans cooler.
uhm, Doesnt willie have a pretty powerful 305? And i know we have a member with a bigass blower ontop of his 305 making over 600 hp iirc.
#9
But i have a 305, and thats what i have to use. If i had the money to do it better and buy a 350, i would. Getting it bored .30 wouldnt be a problem.
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
A simple would have yielded plenty of answers.
However, the question was incomplete. Define "300 horsepower" first - gross flywheel, net flywheel, rear wheel - which one? Because which one makes a big difference.
Gross flywheel is what is quoted for all those magazine articles, crate engines, aftermarket products, etc. It's basically a red herring, and you should pretty much ignore such figures. They are obtained on a dyno with headers, typically a "velocity stack" on top of the carb, with no accessories such as water pump or alternator being powered by the engine. In other words, real world irrelevant.
Net flywheel is what the factory has to use by law, and is similar to gross flywheel except the engine has to be powering the accessories (fuel pump, water pump, alternator, etc.), have the exhaust that would be on it if the engine was in the car, and operated by the same fuel induction system including air cleaner as will be in the the car. Claimed horsepower gains that start with factory ratings and then show gross horsepower after inserting their wizbang product (such as the 335 stroker kit) should be ignored (and a case could be made for such claimers to be shot).
Rear wheel horsepower is the most "real world" because it shows what actually gets to the ground. It is also going to be the lowest number of the 3 types of ratings, and 300 RWHP would be very difficult for a non-power-adder, streetable 305 to obtain.
However...
You can get respectable power out of a 305 without having to touch the shortblock. Assuming your shortblock is in good condition. The combination in the sig produces about 245 rear wheel horsepower, based on drag strip results and a few conversion factors applied. Desktop Dyno says it's 362 HP at 6000 RPMs - that's a gross flywheel estimation.
However (and there are always plenty of "howevers" in life)...
If you need to apply a Summit rebuild kit to a 305 bottom end - forget it. You're wasting your money. Find a rebuildable 350 - may not drop in your lap, but spend the time to find one. Even getting a crate 350 shortblock makes more sense $'s/HP-wise than rebuilding a 305 shortblock.
See https://www.thirdgen.org/techbb2/sho...hreadid=255367 lest you think I'm biased against 305's. It's not bias when it's common sense.
And we didn't even touch whether the proposed combination needs to be emissions-legal...
However, the question was incomplete. Define "300 horsepower" first - gross flywheel, net flywheel, rear wheel - which one? Because which one makes a big difference.
Gross flywheel is what is quoted for all those magazine articles, crate engines, aftermarket products, etc. It's basically a red herring, and you should pretty much ignore such figures. They are obtained on a dyno with headers, typically a "velocity stack" on top of the carb, with no accessories such as water pump or alternator being powered by the engine. In other words, real world irrelevant.
Net flywheel is what the factory has to use by law, and is similar to gross flywheel except the engine has to be powering the accessories (fuel pump, water pump, alternator, etc.), have the exhaust that would be on it if the engine was in the car, and operated by the same fuel induction system including air cleaner as will be in the the car. Claimed horsepower gains that start with factory ratings and then show gross horsepower after inserting their wizbang product (such as the 335 stroker kit) should be ignored (and a case could be made for such claimers to be shot).
Rear wheel horsepower is the most "real world" because it shows what actually gets to the ground. It is also going to be the lowest number of the 3 types of ratings, and 300 RWHP would be very difficult for a non-power-adder, streetable 305 to obtain.
However...
You can get respectable power out of a 305 without having to touch the shortblock. Assuming your shortblock is in good condition. The combination in the sig produces about 245 rear wheel horsepower, based on drag strip results and a few conversion factors applied. Desktop Dyno says it's 362 HP at 6000 RPMs - that's a gross flywheel estimation.
However (and there are always plenty of "howevers" in life)...
If you need to apply a Summit rebuild kit to a 305 bottom end - forget it. You're wasting your money. Find a rebuildable 350 - may not drop in your lap, but spend the time to find one. Even getting a crate 350 shortblock makes more sense $'s/HP-wise than rebuilding a 305 shortblock.
See https://www.thirdgen.org/techbb2/sho...hreadid=255367 lest you think I'm biased against 305's. It's not bias when it's common sense.
And we didn't even touch whether the proposed combination needs to be emissions-legal...
Last edited by five7kid; 08-30-2004 at 02:03 PM.
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Originally posted by GangsteressRide
Getting it bored .30 wouldnt be a problem.
Getting it bored .30 wouldnt be a problem.
.30" is entirely too much to bore any factory small block.
(I realize that was probably a typo on your part, but we do get the "can I bore a 305 to 350" question all too often. 3.736" to 4.036" would be a .30" overbore, but it ain't gonna happen.)
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Car: Firebird
Engine: 388 Stroker
Transmission: Trubo 400
well my friend re-built his 305 in his firebird, it puts about 390. He went with a stroker kit, .30 over, and little things, upgraded the intake and carb.
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Originally posted by 90Firebird550
well my friend re-built his 305 in his firebird, it puts about 390. He went with a stroker kit, .30 over, and little things, upgraded the intake and carb.
well my friend re-built his 305 in his firebird, it puts about 390. He went with a stroker kit, .30 over, and little things, upgraded the intake and carb.
But, you can't bore a 305 .30" over, so...
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Car: 83Z28 HO
Engine: Magnacharged Dart Little M 408
Transmission: G Force 5 speed
Axle/Gears: Moser 9" w/Detroit Trutrac
Originally posted by five7kid
A .30" over 305 with a 3.75" stroke would be slightly over 383 CID.
But, you can't bore a 305 .30" over, so...
A .30" over 305 with a 3.75" stroke would be slightly over 383 CID.
But, you can't bore a 305 .30" over, so...
Won't give you a 383 though! Seriously, I rebuilt my 305 and really have no regrets- but that's me.
I know I wasn't pushing 300 HP with it, but yet I wasn't a bit afraid of stock 350's. I've owned 350's in the past that seemed much slower than my slightly built 305 HO....
BUT - I ended up with a 400 under the hood.....go figure.
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Car: 1966 impala , 1998 sebring vert,1978 buick regal turbo, 1991 chevy silverado 3/4ton 4x4 lifted
Engine: 283, 2.5,3.8 turbo 350
Transmission: powerglide,auto overdrive, th350,4L80
Originally posted by five7kid
But, you can't bore a 305 .30" over, so...
But, you can't bore a 305 .30" over, so...
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Car: 1984 Trans Am WS6
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Nothing new there. The same work and money applied to a 350 would yield over 400 hp.
Rebuilding a 305 lower end is a waste of performance money.
Period.
Still haven't heard if this needs to be an emissions-legal combination in the end.
Rebuilding a 305 lower end is a waste of performance money.
Period.
Still haven't heard if this needs to be an emissions-legal combination in the end.
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Car: 83Z28 HO
Engine: Magnacharged Dart Little M 408
Transmission: G Force 5 speed
Axle/Gears: Moser 9" w/Detroit Trutrac
Originally posted by five7kid
Nothing new there. The same work and money applied to a 350 would yield over 400 hp.
Rebuilding a 305 lower end is a waste of performance money.
Period.
Still haven't heard if this needs to be an emissions-legal combination in the end.
Nothing new there. The same work and money applied to a 350 would yield over 400 hp.
Rebuilding a 305 lower end is a waste of performance money.
Period.
Still haven't heard if this needs to be an emissions-legal combination in the end.
Soooo, let's take it a step further.
The same work and money applied to a 400 would yield even more hp....
Do the same on a 454, and you'll yield even more power than that.
Bottom line: There's no replacement for displacement. Easy enough.
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
400 shortblocks are less commonly available. Use of things such as 305 58cc chamber heads, while possible and effective on a 350, is much less so on a 400. A 400 is also externally balanced, which drives up cost and complexity.
454 is a whole new ballgame. Weight becomes a factor. Cowl hood required (unless you're willing to settle for a hole in the hood). Exhaust is a royal pain. Etc., etc., etc.
For a 300 HP goal, no need to go through those hoops.
454 is a whole new ballgame. Weight becomes a factor. Cowl hood required (unless you're willing to settle for a hole in the hood). Exhaust is a royal pain. Etc., etc., etc.
For a 300 HP goal, no need to go through those hoops.
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Car: 83Z28 HO
Engine: Magnacharged Dart Little M 408
Transmission: G Force 5 speed
Axle/Gears: Moser 9" w/Detroit Trutrac
Originally posted by five7kid
400 shortblocks are less commonly available. Use of things such as 305 58cc chamber heads, while possible and effective on a 350, is much less so on a 400. A 400 is also externally balanced, which drives up cost and complexity.
454 is a whole new ballgame. Weight becomes a factor. Cowl hood required (unless you're willing to settle for a hole in the hood). Exhaust is a royal pain. Etc., etc., etc.
For a 300 HP goal, no need to go through those hoops.
400 shortblocks are less commonly available. Use of things such as 305 58cc chamber heads, while possible and effective on a 350, is much less so on a 400. A 400 is also externally balanced, which drives up cost and complexity.
454 is a whole new ballgame. Weight becomes a factor. Cowl hood required (unless you're willing to settle for a hole in the hood). Exhaust is a royal pain. Etc., etc., etc.
For a 300 HP goal, no need to go through those hoops.
It all boils down to this in my mind:
How fast do you wanna go, and how much do you want to spend to get there?
300 hp isn't all that much to ask out of a 305, and it's even less to ask of a 350 - and so on.
But I'll tell you what - I'm a lot more impressed with a 300hp 305 than I would be with a 300 hp 350!
That's just me though.
But - as I said above, I agree with you 5-7....you're practically buying the same parts to rebuild a 350 at no real additional cost, so why not?
Last edited by Confuzed1; 09-01-2004 at 11:28 AM.
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Car: 1989 FIREBIRD FORMULA WS6
Engine: TPI 305
Transmission: T-5
Well then
What about the small block 454 crate motor. I'm not sure what the company name is, but I have seen articles in hot rod mag and super chevy. If ya applied the same principals to this 454 then it would make more hps than a 350. May be this person like his 305.
#23
May be this person like his 305.
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Car: 1989 FIREBIRD FORMULA WS6
Engine: TPI 305
Transmission: T-5
What like this
What you mean like me spending $700 dollars for my 89 firebird formula WS6 305 TPI with T-5 and 9bolt posi, and then smoking a few 5.0 ponies with about 5 to 7 times the money into their cars. Turnin em and burnin em. It just depends on what you want from your engine and car. If it's a daily driver/ slight street racer, and you want a straight drop in go with a 305. But if ya want to get it to go faster cheaper, now would be the time to up the displacment of your motor. If I spent 1500 on a 305 and 1500 on a 350 ( assuming engine is in the same condition ) the 350 would go faster, with more horspower.
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
The L69 & TPI guys are in a lot better shape in that regard than LG4 or LO3 guys are. The intake & exhaust of L69/TPI can support a 350 (minor TPI mods needed, like AFPR and possibly injectors), however the LG4 and LO3 exhaust cannot support a 350 (can't support a 305, for that matter). So, the "supporting cast" has to be handled first.
$1500 for a 350 to replace an LG4 with nothing else changed will be slower than $1500 spent to upgrade exhaust, cam, air cleaner and port the heads on an otherwise sound 305. LO3 would also require PROM tuning and injector upgrades, so $1500 probably wouldn't quite cover it.
$1500 for a 350 to replace an LG4 with nothing else changed will be slower than $1500 spent to upgrade exhaust, cam, air cleaner and port the heads on an otherwise sound 305. LO3 would also require PROM tuning and injector upgrades, so $1500 probably wouldn't quite cover it.
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Car: 1983 Z28
Engine: 383
Transmission: 700R4
I did a cheapo rebuild on my 305 in my 83Z
edelbrock rpm manifold
comp 268h cam
flat top cast pistons
I used the stock metal shim gasket,did some porting on the heads,just basic gasket match and cleaned up the short side radius.
i used some cheap headers,and man what a difference really woke up the engine.It wasnt stupid fast but it was a blast to drive.The machine work consisted of having the block cleaned and punched out 30,crank polished.
This was 10 years ago now,I think the pistons cost me 80bux cdn.
If i had to do it again though id get one of gm cheapo crate motors,Plenty of power and a good foundation for later upgrades
edelbrock rpm manifold
comp 268h cam
flat top cast pistons
I used the stock metal shim gasket,did some porting on the heads,just basic gasket match and cleaned up the short side radius.
i used some cheap headers,and man what a difference really woke up the engine.It wasnt stupid fast but it was a blast to drive.The machine work consisted of having the block cleaned and punched out 30,crank polished.
This was 10 years ago now,I think the pistons cost me 80bux cdn.
If i had to do it again though id get one of gm cheapo crate motors,Plenty of power and a good foundation for later upgrades
#28
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Car: '85 Camaro
Engine: LG4 305
Transmission: T-5
Could it be said that the main reason one would build a 305 is so they don't have to go through the extra expense of upgrading the transmission and rear end for the additional torque?
Jason
Jason
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Car: 1966 impala , 1998 sebring vert,1978 buick regal turbo, 1991 chevy silverado 3/4ton 4x4 lifted
Engine: 283, 2.5,3.8 turbo 350
Transmission: powerglide,auto overdrive, th350,4L80
Originally posted by jrg77
Could it be said that the main reason one would build a 305 is so they don't have to go through the extra expense of upgrading the transmission and rear end for the additional torque?
Jason
Could it be said that the main reason one would build a 305 is so they don't have to go through the extra expense of upgrading the transmission and rear end for the additional torque?
Jason
if you are going from a 305 to 350 the transmission and rearend will handle alot of abuse before it needs upgrading..
thats not a good reason to build a 305 thats a bad excuse ...LOL
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Car: 1966 impala , 1998 sebring vert,1978 buick regal turbo, 1991 chevy silverado 3/4ton 4x4 lifted
Engine: 283, 2.5,3.8 turbo 350
Transmission: powerglide,auto overdrive, th350,4L80
there are lots and lots of guys running a t-5 with a 350 that are running in the 300+hp range and not having any problems with thier transmissions at all....
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Car: '85 Camaro
Engine: LG4 305
Transmission: T-5
I thought running a T-5 with a 350 was one of those abominations that 3rd gen owners don't do. From what I've read the actual Case can split apart. Are these guys just choosing to let the thing break then upgrade?
I haven't done either so I am not claiming to be an expert at all. I agree that building a 350 preferrable to a 305. But if you just recondition the rods and crank, get new pistons and call it a day that is a whole lot less than a 350, even if it is just the fact that you don't have to buy a sued one to start with. From a purely short term cheap route the 305 is sufficient.
This doesn't even consider that according to this board there are NO good stock 350 heads, while the '416 and '081(?) are workable with a homemade port and polish with bigger intake valves with a 305. Locally that's about $300 vs. $500 for some new vortecs (which the car did not come with) that require a new intake manifold to boot.
It is better to build a 350. But if it means that you don't get in the game because of all the "might as well's" then build the 305, and just plan on more later.
Jason
I haven't done either so I am not claiming to be an expert at all. I agree that building a 350 preferrable to a 305. But if you just recondition the rods and crank, get new pistons and call it a day that is a whole lot less than a 350, even if it is just the fact that you don't have to buy a sued one to start with. From a purely short term cheap route the 305 is sufficient.
This doesn't even consider that according to this board there are NO good stock 350 heads, while the '416 and '081(?) are workable with a homemade port and polish with bigger intake valves with a 305. Locally that's about $300 vs. $500 for some new vortecs (which the car did not come with) that require a new intake manifold to boot.
It is better to build a 350. But if it means that you don't get in the game because of all the "might as well's" then build the 305, and just plan on more later.
Jason
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Car: 1966 impala , 1998 sebring vert,1978 buick regal turbo, 1991 chevy silverado 3/4ton 4x4 lifted
Engine: 283, 2.5,3.8 turbo 350
Transmission: powerglide,auto overdrive, th350,4L80
Originally posted by jrg77
I thought running a T-5 with a 350 was one of those abominations that 3rd gen owners don't do. From what I've read the actual Case can split apart. Are these guys just choosing to let the thing break then upgrade?
I haven't done either so I am not claiming to be an expert at all. I agree that building a 350 preferrable to a 305. But if you just recondition the rods and crank, get new pistons and call it a day that is a whole lot less than a 350, even if it is just the fact that you don't have to buy a sued one to start with. From a purely short term cheap route the 305 is sufficient.
This doesn't even consider that according to this board there are NO good stock 350 heads, while the '416 and '081(?) are workable with a homemade port and polish with bigger intake valves with a 305. Locally that's about $300 vs. $500 for some new vortecs (which the car did not come with) that require a new intake manifold to boot.
It is better to build a 350. But if it means that you don't get in the game because of all the "might as well's" then build the 305, and just plan on more later.
Jason
I thought running a T-5 with a 350 was one of those abominations that 3rd gen owners don't do. From what I've read the actual Case can split apart. Are these guys just choosing to let the thing break then upgrade?
I haven't done either so I am not claiming to be an expert at all. I agree that building a 350 preferrable to a 305. But if you just recondition the rods and crank, get new pistons and call it a day that is a whole lot less than a 350, even if it is just the fact that you don't have to buy a sued one to start with. From a purely short term cheap route the 305 is sufficient.
This doesn't even consider that according to this board there are NO good stock 350 heads, while the '416 and '081(?) are workable with a homemade port and polish with bigger intake valves with a 305. Locally that's about $300 vs. $500 for some new vortecs (which the car did not come with) that require a new intake manifold to boot.
It is better to build a 350. But if it means that you don't get in the game because of all the "might as well's" then build the 305, and just plan on more later.
Jason
if your going to do the work to a 305 then youd be alot better off doing it to a 350 ....there is no replacement for displacement... as for the heads issue yes you are correct to say that there arent very many good heads that came stock on a 350 but thier are alot to work with expecially when you look at putting a set of 305 heads on a 350 with some work done to them ....not only will it give you better compretion but you already have the heads if you are going from a 305 to 350.....
look at it like this if you are just wanting to get your car moving and dont have much funds yes rebuild your 305 to stock and go ....but if you want to build something for performance then its rediculous to build a 305 when everything you put on it you could have put on a 350 and made more power....
#36
i think 335tpi has a nice setup he is doing 13 second quarter mile.
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Car: 1987 Camaro Z28
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TOO MUCH COMPETITION!!!
Im getting too many awswers here. Ones arguing 350, ones arguing 305, ones arguing 383, and another doesnt care.
Ok, what are the benefits of rebuilding a 305, or a 350? Which will be cheapest and best, and not overkill. Yes, we have to be emmisions legal. I just want some respect while driving a camaro. Smoke some Neons and Civics or somethin."
"It's a GM, I don't ask questions"
Im getting too many awswers here. Ones arguing 350, ones arguing 305, ones arguing 383, and another doesnt care.
Ok, what are the benefits of rebuilding a 305, or a 350? Which will be cheapest and best, and not overkill. Yes, we have to be emmisions legal. I just want some respect while driving a camaro. Smoke some Neons and Civics or somethin."
"It's a GM, I don't ask questions"
#38
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Car: '83 Z28, '07 Charger SRT8
Engine: 454ci, 6.1 Hemi
Transmission: TH350, A5
Axle/Gears: 2.73 posi, 3.06 posi
If I wanted a 300hp 305, this is where I would start:
- Bore the block .030 and have all needed machine work done
- Port a set of 416/601/081 heads, add 1.94 and 1.6 valves
- Flat top pistons
- Perf RPM manifold
- 650cfm Double Pumper 4bbl
- 1-5/8" headers from Hooker, Hedman, etc
I dunno about the cam though, never been good at cam stuff.
- Bore the block .030 and have all needed machine work done
- Port a set of 416/601/081 heads, add 1.94 and 1.6 valves
- Flat top pistons
- Perf RPM manifold
- 650cfm Double Pumper 4bbl
- 1-5/8" headers from Hooker, Hedman, etc
I dunno about the cam though, never been good at cam stuff.
#39
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Car: '85 Camaro
Engine: LG4 305
Transmission: T-5
The easiest way to answer your question is how cheap is cheap to you? Given a dollar amount the answers get easier.
It also helps to know if your car has a carb or TPI.
There's a tie for absolute cheapest. You can rebuild your engine or buy a crate 350.
For a few dollars more is a 383 which is just a 350 with some changes on the internals. Depending on how badly you want to beat the 4 bangers or how much work they've done on them will determine how much more expensive it will get.
Under $1000 work with what you've got. You may get to 300hp you may not.
$1000-2000 get a 350.
$2000 and up get a 383.
Hope that helps.
Jason
It also helps to know if your car has a carb or TPI.
There's a tie for absolute cheapest. You can rebuild your engine or buy a crate 350.
For a few dollars more is a 383 which is just a 350 with some changes on the internals. Depending on how badly you want to beat the 4 bangers or how much work they've done on them will determine how much more expensive it will get.
Under $1000 work with what you've got. You may get to 300hp you may not.
$1000-2000 get a 350.
$2000 and up get a 383.
Hope that helps.
Jason
#40
what are the benefits of rebuilding a 305, or a 350
#41
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Car: 1987 Camaro Z28
Engine: 5.0, 305, V8, 4BBL
Transmission: 700R4
I was told the carb on my car cant be changed without doing serious work, because its the electronic controlled Carb, "Mechanics Nightmare". So thats all ran off the computer. I dont know whats involved changing over a carb on this car, but I was told you cant without doing serious work.
Money spending wise, I would say like 1,000-1,500. I just have to know exactly what to get, how to tune, and stuff like that. Also why was the one guy saying you cant bore a 305 .30 over? I thought you could. Thanks guys for helping so far, im new at this stuff.
:rockon: :hail:
Money spending wise, I would say like 1,000-1,500. I just have to know exactly what to get, how to tune, and stuff like that. Also why was the one guy saying you cant bore a 305 .30 over? I thought you could. Thanks guys for helping so far, im new at this stuff.
:rockon: :hail:
#42
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Car: '85 Camaro
Engine: LG4 305
Transmission: T-5
The correct term is .030 over, not .30 over.
With $1500 max don't even think about swapping to EFI. You just want to replace the stuf under the carb. A basic 350 should suffice. The $1500 will buy a new crate engine. You would still have to pay the mechanic to replace your current engine with it, unless you do it yourself.
I hope this isn't your daily driver, cause it will be a couple of days, and your mechanic doesn't really sound interested.
Jason
With $1500 max don't even think about swapping to EFI. You just want to replace the stuf under the carb. A basic 350 should suffice. The $1500 will buy a new crate engine. You would still have to pay the mechanic to replace your current engine with it, unless you do it yourself.
I hope this isn't your daily driver, cause it will be a couple of days, and your mechanic doesn't really sound interested.
Jason
#43
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Car: 1992 Camaro RS
Engine: L03
Transmission: 700R4
Axle/Gears: Stock
I'm sure that GangsteressRide is well aware that a 350 can put out much more power. But he didn't say anything about putting a 350 in the car. Maybe he has a great 305 thats still running strong and wants to rebuild it and put some work into it to make it a kickass engine, instead of being a lazy *** and just dropping in a 350 like everyone else and their mother does. I salute him for wanting to build a bitchin' 305 and if I had the money I would do the same. Because where's the challenge/fun in building up a 350? Besides, it's gonna be very rewarding to snuff out some of you 350 guys with lil' 305. GangsteressRide... you're gonna have to redo the entire engine. Get some World Torquer or L98 heads a new valvetrain and exhaust and you can figure it out from there.
#45
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Car: 88 Firebird
Engine: 350 LO5 TBI
Transmission: 700R4 Vette Servo/Shift
take cadillac's advice and check out that webpage. If you have $1500 then your set for 300+ hp.
L31 Vortec Heads $600 Assembled
Edelbrock RPM intake $150-200
750 Holley $150-200
Comp Cam $100-200
spend the rest on exhaust.
Youll be good for 300hp at least
but you need to grab 3.73 gears and a decent stall so add another $300-$400 at least.
(Also consider upping your wires ($60), ignition ($150), and fuel pump ($150)
worst case is about $2000.
Now consider finding a 350 Block for $300-600, then buying decent heads, intake, exhaust, and carb and doing the complete swap. Youll need a new knock, and computer. In the end you have more oppertunity down the road. But you spend an extra $600-$1000 minimum and lots of time just to get around the same results. The main difference is that the 350 isnt already there. So you have to consider everything needed for a swap before looking for hp figures
I personally did a 350 swap instead of 305 build-up and so now considering heads and bottom end is easy since Im not debating 305 or 350. I know its not much help but thats my personal account. Goodluck
L31 Vortec Heads $600 Assembled
Edelbrock RPM intake $150-200
750 Holley $150-200
Comp Cam $100-200
spend the rest on exhaust.
Youll be good for 300hp at least
but you need to grab 3.73 gears and a decent stall so add another $300-$400 at least.
(Also consider upping your wires ($60), ignition ($150), and fuel pump ($150)
worst case is about $2000.
Now consider finding a 350 Block for $300-600, then buying decent heads, intake, exhaust, and carb and doing the complete swap. Youll need a new knock, and computer. In the end you have more oppertunity down the road. But you spend an extra $600-$1000 minimum and lots of time just to get around the same results. The main difference is that the 350 isnt already there. So you have to consider everything needed for a swap before looking for hp figures
I personally did a 350 swap instead of 305 build-up and so now considering heads and bottom end is easy since Im not debating 305 or 350. I know its not much help but thats my personal account. Goodluck
Last edited by Avenger007; 10-24-2004 at 08:39 PM.
#46
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Originally posted by GangsteressRide
I was told the carb on my car cant be changed without doing serious work, because its the electronic controlled Carb, "Mechanics Nightmare". So thats all ran off the computer. I dont know whats involved changing over a carb on this car, but I was told you cant without doing serious work.
I was told the carb on my car cant be changed without doing serious work, because its the electronic controlled Carb, "Mechanics Nightmare". So thats all ran off the computer. I dont know whats involved changing over a carb on this car, but I was told you cant without doing serious work.
Money spending wise, I would say like 1,000-1,500. I just have to know exactly what to get, how to tune, and stuff like that.
The air cleaner (small, but important, detail), assuming you have an LG4, which is most likely. You need a dual snorkel air cleaner, either a factory-type one, or one that's fabricated. An open element will do, but it is less desireable, and is not emissions-compatible.
Then cam.
Then head porting.
If any money needs to be spend on things like rings, bearings, or pistons for the 305, cut your losses and go find a 350 to rebuild. Seriously.
The sig in my original post is a 350 GFWHP combo on desktop dyno, performance indicates 250 rear wheel horsepower. With the stock computer controlled carb.
Last edited by five7kid; 10-25-2004 at 06:07 PM.
#47
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Car: '84 Berlinetta
Engine: 305
Transmission: A4
http://www.hioutput.com/tech/343hp/343hp.html
this arcile can help you find some ideas
i know the 305 Vs. 350 arguement could go on forever but seriously about the whole "no replacement for displacement" i dont believe its entirely true, at the same time yes i agree bigger is better but at the same time i think its quite possible for a fully tricked out 305 equiped with low compression pistons, a turbo or two, or even a supercharger would kick some serious @$$ and be able to beat out alot of lager displacement engines (given that they dont have the same amount of work done as you, in which, yes displacement would previal)
besides all that, if you really know what your doing anyone could potentially make some boss power from any engine dispite displacement.
this arcile can help you find some ideas
i know the 305 Vs. 350 arguement could go on forever but seriously about the whole "no replacement for displacement" i dont believe its entirely true, at the same time yes i agree bigger is better but at the same time i think its quite possible for a fully tricked out 305 equiped with low compression pistons, a turbo or two, or even a supercharger would kick some serious @$$ and be able to beat out alot of lager displacement engines (given that they dont have the same amount of work done as you, in which, yes displacement would previal)
besides all that, if you really know what your doing anyone could potentially make some boss power from any engine dispite displacement.
Last edited by berlinator; 10-26-2004 at 09:19 AM.
#48
Maybe he has a great 305 thats still running strong and wants to rebuild it and put some work into it to make it a kickass engine, instead of being a lazy *** and just dropping in a 350 like everyone else and their mother does.
L98 heads a new valvetrain and exhaust and you can figure it out from there.
#49
what about LPE 211/219 cam, and superram on World S/R's torquers with minor port job. should make close to 325 hp if not more.
fully upgraded Large runners and ported base setups should easily flow tons of air for the 305 cuz its designed for it LOL. Should be easy to make 300hp+ with 210/220 cam from comp cams and those World heads, but i guess other heads can be used as well like L98's vette heads. That be nice mid 13's or better combo for sure.
fully upgraded Large runners and ported base setups should easily flow tons of air for the 305 cuz its designed for it LOL. Should be easy to make 300hp+ with 210/220 cam from comp cams and those World heads, but i guess other heads can be used as well like L98's vette heads. That be nice mid 13's or better combo for sure.
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Car: 1966 impala , 1998 sebring vert,1978 buick regal turbo, 1991 chevy silverado 3/4ton 4x4 lifted
Engine: 283, 2.5,3.8 turbo 350
Transmission: powerglide,auto overdrive, th350,4L80
Originally posted by berlinator
i know the 305 Vs. 350 arguement could go on forever but seriously about the whole "no replacement for displacement" i dont believe its entirely true, at the same time yes i agree bigger is better but at the same time i think its quite possible for a fully tricked out 305 equiped with low compression pistons, a turbo or two, or even a supercharger would kick some serious @$$ and be able to beat out alot of lager displacement engines (given that they dont have the same amount of work done as you, in which, yes displacement would previal)
i know the 305 Vs. 350 arguement could go on forever but seriously about the whole "no replacement for displacement" i dont believe its entirely true, at the same time yes i agree bigger is better but at the same time i think its quite possible for a fully tricked out 305 equiped with low compression pistons, a turbo or two, or even a supercharger would kick some serious @$$ and be able to beat out alot of lager displacement engines (given that they dont have the same amount of work done as you, in which, yes displacement would previal)
you went back and forth 4 times ...LMAO..LOL