83 Crossfire TA

iTrader: (2)

3.736”

A larger bore allows for a larger unshrouded valve area which helps breathing.

OTOH, it also makes for a larger, more spread out chamber which results in a slower, less efficient burn that is more prone to detonation issues…

PROPHET69

305? 350? Screw em Both. Give that to your grandma and find yourself a chevy 400 ci . If you're modding out an engine for hp and torque, might as well make your money really worth it.

Here ya go, you can start with one of these:

http://cgi.ebay.com/ebaymotors/Small...11294542QQrdZ1

http://cgi.ebay.com/ebaymotors/Chevr...00942085QQrdZ1

http://www.customdesignperformance.c...vyengines.html

http://www.comeracing.com/weblog/2006/06/08.html

Bitchin!!

RebelGQ

Has anyone heard of this ford slogan?

Have you beaten a Ford lately?

1991Formula350

I finally went this past weekend and had a 3:42 gear put in, WOW, what a difference! The gear and kit was 300.00 and parts and gear oil was on 280.00.also had a part to be replaced that was 160.00 ( forgot the part ).

Now I plan on getting headers ( car is a '91 305 ) and 3" exhaust to compliment that. Thanks to all posts!

Andy

Guest

Other way around. LS1/LS6 are closer to 4" than 3.736". But GM is moving away from that anyway, the LS2, LS3, LS7, and probably LS9 are all 4" or more.

jay_d

to everybody arguing over moters.....305=P.O.S 327....decent moter, but by the time u reached your optimium rpm range(which is very high) the 350 has done hit its "happy place" caught another gear and is half way down the track......the only thing a 327 is good for is a "correct" resoration on a vette.......plus......have u ever seen a 4 bolt main 327 or 400 sb? no.....A 350 is the moter to tune in on because the parts are available...and if u sling a rod.....so what go to the junk yard and pick up a new block...327, 400.....things aint that simple...my point 350's are available....( oh yeah, and the 400....while it may be able to smoke the 350 with similar mods, well...i just hope u aint doin 2 races back to back.....cause u gonna run hot as hell...)

junkcltr

iTrader: (1)

I don't know why 305ci gets a bad rep. My stock 305 with over 135K miles is putting out about 310 FWHP right now. The plan is to turn up the compressors and make a peak 400-425 FWHP at 5000 RPM. The 305 engines (not "moters") seem OK to me.

327_TPI_77_Maro

iTrader: (8)

3.7 bore, see 1st page. I had an extra set of world products sportsman heads kicking around, but realized I'd have to notch a 305 I have in one of my cars just to use them. LOL.

Stephen

iTrader: (12)

FWHP? What front wheel driver, do you have a 305 in?

327_TPI_77_Maro

iTrader: (8)

Oh my God are you for real? FWHP = flywheel horsepower. LO

Stephen

iTrader: (12)

Yes, I'm for real...

RWHP=Rear wheel Horse Power
FWHP=Front Wheel Horse Power

For all I knew, you were referring to an older Olds Toronado, that has a tranverse V8, and FWD.

PETE

iTrader: (1)

There is no reason a small bore motor can't make decent power. You do not need a 2.02 valve in the smaller cylinder. Y0ou can run a 2.00 valve on a conservative cam.

As for the larger motors outrunning it I should hope so. But think of this. How many 10 second cars do any of the naysayers here own or have seen?

The 305 can produce more than enough power to surprise 9 out of every 10 cars it lines up against.

I'd like to here that crybaby argument after getting your **** handed to you by a 305.

Try telling the guy he shoulda went a with a 350 instead of that 305! What will be your reasoning? He woulda laid an even bigger beatdown on you!

If I ever sell the TTA I'd love to build a 305 motor.

Splay/stud the mains(already have em), Vortec heads Max port(no reason to machine the pockets I'd use a smallish cam), I'd use the TPI with a vortec base and at least a T-66 turbo. If the heads turn out that good it may be able to use a T-70. All but the most hearty of cars on this board wont be able to hang with it.

Who wants to donate a 305 Tpi car to me for the test..... I have the hotside parts, splayed caps, studs, fuel pump, DFI, etc......

Street Lethal

iTrader: (16)

Don't know either. Everytime I hear that I'm immediately reminded of an article that TPI-454 posted a few years back. Click Here....

83 Crossfire TA

iTrader: (2)

As much as I’m all for going fast with a 305, Smitty’s car is not a good example, since it’s only a 305 WRT to displacement, not wrt to the 305’s limitations, that thing has a 4” bore, and he’s not so much going fast with a 305, but going fast with an overbored 302 or destroked 350 (355…).

1984Z28HO

everybody talks all this crap about 305s.. really nothing wrong with them.. if you have the older cheaper lg4 motors then yes they are just about worthless.. l69 are the best.. flat top pistons, put a cam intake and carb on them along with some 3:73 and it will leave most 350s behing along with almost any 4.6 mustang.. they are a very rev happy motor, mine pushes 6500rpm on stock internal and i have never pulled the heads off.. still factory sealed.. its also all in the driver..

PETE

iTrader: (1)

The car still ran low 11's on a stock block 305 with the supercharger. Even that car woulda spanked most of the clowns on any board bashing the 305.

It's a preference.

With the wide spread use of turbochargers now any engine can make gobs of power. When you to the track now a days you see all types of cars putting down disgusting numbers they normally couldn't do....

Last time out I saw a BMW, a few Fox Bodied Stangs and the normal cars like Evo's, STI's, older Toyota's etc. That argument on displacement should only be compared factory equipped or for n/a comparisons.........

Orr89RocZ

iTrader: (20)

yep larger bores can flow more air, thats why you need to watch out for aftermarket head companies flow numbers.. you need to see what bore they flowed those heads on, alot of them use large 4.125+ inch bores and those numbers look good for that application but not so much on a 4.030 bore.

305 TPI cars arent bad but they really need a cam/head work then abit of intake work to compete.

there are several guys on this board now with 12 second cammed/headed 305's. some with carbs, some with fuel injection. Granted it only took my L98 with bolt ons to get a 12.9 pass and if i add a cam to the stock longblock, i'll be deep 12's more than likely.

BUT a hotcam and a HSR with proper gear will SCREAM on the topend in a 305. may not make alot of bottom end but damn it be like a 302 DZ engine for sure.

If you dont want to spend the money on all that work, ie heads/cam/intake bolt ons, etc, then just get a procharger and be done with it. should make near 200whp stock and then jump to 350whp or more with the blower

91Bird305

You realize you can build a decent 350 small block for around 1K right? Why dump tons of money into that 305 when you can just create a cheap, more powerful 350 and then add whatever power adder you want. You will spend a lot less money making a 350 faster then a 305.

getchevy

question for you? have a 87 iroc 350 5.7l tpi. stock it has 225 horses, trying to get up to 300 to 350 horses. what can i add?

91Bird305

A mild head and cam package can get your 300-350 easy (including exhaust work). Talk to your local performance shop and ask them what they have been using. That way you know it is proven and they know how to tune for it.

8T9 BANDIT

i regularly smoke stock l98 cars
----------
on the street that is

91Bird305

with your modified LB9? Good work. I think you are missing the point...

8T9 BANDIT

im not missing the point. i know same $ into a 350 will give u more hp than the same $ in a 305. most of my mods are bolt on's so if the old lb9 ever pops it will all go to a nice stroker.. 305's are still great street machines if done right. and i surprise the hell out of most people.. when i say its just a 305. especially the 4th gen guys. i will be adding a crane 2032 and a prochager over the next few months.. and yes it will be fun!

junkcltr

iTrader: (1)

Why not just put a 350ci in it and still say that it is just a 305ci? Most people can't tell the difference and most really don't care anyway (even though they act surprised). 265/283/302/305/327/350/400...........build the one that excites you most.

8T9 BANDIT

i really dont like to lie to people.. thats pretty stupid. saying u have a 305 when u have a 350 is just dumb. ill stick with my plans.

junkcltr

iTrader: (1)

Exactly, bragging about a 305ci is the same. People aren't trying to shoot down your 305ci plans. They are just trying to let you know that the engine config. is not cost effective when compared to other blocks. I have a 305ci with boost and when it croaks a 350ci will probably replace it.

8T9 BANDIT

tell me about youre boosted 305,, specs hp. tq what kind of sc..

junkcltr

iTrader: (1)

All the info for it is here:
https://www.thirdgen.org/forums/powe...turbo-tpi.html

It is slow, but fun.

junkcltr

iTrader: (1)

According to the calcs it puts out about 340-350HP at the crank.

91Bird305

Exactly.

One thing I learned thru all the years, don't **** around with **** that you know your going to replace later down the road. It is just a waste of money and time. If I could go back in time and tell myself "Don't modify that 305, it's a waste, this is why..." then I would. There is just a lot better out there for a lot cheaper and more cost effective in the long run and I could have saved so much money and time if I would have just started with my current motor I have now, then trying to make my 305 fast before. That whole "Well I like it because its a 305 and I shock people" is a lame excuse. The only people you are shocking are 13-14 second cars. When it comes down to it, it isn't fast and you will want to go faster in the future, which will involve you replacing that motor with something bigger or better, so why dump money into it?

That is just my 2 cents.

*This rule doesn't go towards the things that can be swapped onto a different motor. ie: nitrous, headers, etc...

8T9 BANDIT

dude, tahts exactlly what i said.. its a bolt up car.. everything could be swapped to a diff motor.. most of my mods are suspension/exhaust and such.. and the sc will also go to a bigger motor.. but this is a street car. not a track car. i dosent matter to me if i run a 12.7 with a blown 305 or a 12.2 with a 350.. its a street machine. and a dahm nice one to add. and i dont do ANYTHING to impress anybody!! everything i do is to satisfy myself. and what i want. not to mention there's a ton of 305's on these boards running 13's and 12's which to me, is a fast street car.

91Bird305

Where I am from, those are stock Ls1 times.

All I am saying is if your going to do it, do it right and not waste your time. But to each their own. I just couldn't stand myself if I had a supercharged V8 that ran 12's or 13's. That would **** me off.

Guest

That all depends on what you spent. I havent had any trouble with any LS1 cars and I have less in it than a typical engine rebuild cost so the cost/benefit ratio is pretty good.

ZONES89RS

iTrader: (2)

Bottom line is if you are looking for power and speed you want to avoid a 305. Stock a 305 is junk, but you can make anything fast with money. It really is not cost efficient to use a 305. They are good for a ton of nitrous or forced induction due to keeping cool easy, but as usual the more cubes would make more HP.


I have had 2.8 V6-455 pontiac, and as usual i will olmost allways pick more cubes.


jay_d -Yes they made a 400 small block with 4 bolt mains, but it is even said the 2 bolt is stronger.

91Bird305

Details please?

8T9 BANDIT

ok,, im sick of arguing with children about what motor is better.. duh. common sense more cubes = more power.. we all know this. but why do u children insist on ragging on the motors that the majority of our cars came with from the factory?? modding one and running fast is a good thing. and when it dies, u go bigger and better. if u dont like a stock thirdgen powertrain. then dont comment on them. if u can help people on this forum with some good info, then give it. or go surf the web. im just sick of hearing 350's r faster drrrrrrrrrrrr,, $%&(++_!@# no f-in sh++,, but so is a 400, 396, 454, 383, 502 and so on... and one last word. i will be glad to run anybody thats runs there mouth on how 305's suck, if they have a stock or mild 350. any offers????? grow up already people! just answer peoples questions. not " u duh get a 350? duh"

Guest

13.8@104 with a 2.3 60' time and 7-8psi, only time I ever took it to the track. With a decent 60 (I was on old worn out street tires) you can go ahead and figure out what it would have ran. I'm now running twice that psi and havent had much trouble with anything I've come across on the road although quite a few have tried. Hey its a thirdgen, its supposed to be slow.

Only thing thats done other than the Vortech is some SLP headers and a catback. I got the s/c used so... not much invested and it was a fairly simple bolt on. Would a 350 run faster? Probably. But I dont have one, and the 305 is fine so far so... no reason to change it unless I feel like it. I was not trying to build the fastest car, just playing around with what I've got and its been fun.

91Bird305

The GN, TTA, SRT4, Skyline,EVO, etc...guys might disagree with that.

People, not kids, are simply giving advice on the subject, people with experience on both sides of the fence. It would be irresponsible, dumb, and boring, if no one was to comment on something they don't agree with and have common knowledge about.
We did give it. This is actually info that is meant to inform you or help you. Not to "rag on".

LoL, why does it have to be stock or mild? They can't have the same mods you do? L98 with your suspension and gears > LB9 with the same setup. I don't know why you would call that out.

We are. It is really just that simple. Get rid of the 305 and don't bother with it unless you like spending lots of money to run 13's or 12's.

So you run low to flat 13's with a supercharged V8. Been to the track with 16psi yet?

ZONES89RS

iTrader: (2)

Well, when you go with boost things change, you cannot really compare that apples to apples. You speak thru the N/A to N/A. More mods for any cubes yields more gains.

91Bird305

That is true but there is a point where technology starts to compenstate for cubes. Not that GN's or TTA's are very high tech, I meant for the other applicants.

Guest

Havent been to the track yet but I dont see mid 12's being an issue.

91Bird305

Get your 60 ft problem fixed? What was the issue?

8T9 BANDIT

dude, u must have contradicted youreself about 3 times already.. i think most of us know about tta's and gn's now youre saying forget cubes when u have boost. before u were saying get 45 more cubes.. dude just stop already! youre remarks are BS u sound like hillary clinton at a debate full of s+++! enjoy youre boosted v6 and ill enjoy my supercharged lb9. but youre still a jack==== for puting down anyones motor here on this forum. .. i just had an idea, wouldnt youre car be faster with a 400 block rather than that 3.8??????????????

8T9 BANDIT

hey 91bird,, you know, if u added moore boost youre car would go faster? hey if u added more cubes youre car would be faster? if u added both youre car would be faster? hey if u twin turbocharged a big block and added a 300 shot of juice yure car would be really fast? just stop stating the obvious.

91Bird305

It could.

But 400's like to crack sometimes at the mains so I probably wouldn't go with a 400.

I never said that. I said eventually technology does start making up for cubes. Eventually. Not right away.

My remarks are not BS or full of ****. Please tell me how they are instead of just saying "BS" when you provide no facts behind the statement.
And I am not putting it down, the question was asked, should I modify my 305? I simply anwsered with "no, your money will go a lot furthur with a different motor." It's a fact. I have been on both sides and I just don't find any sense of dumping time and money into a motor that barely produces and competes with real street cars.

91Bird305

Depends on the turbo. Turbos normally have a "max boost". Mine is 25-26lbs. Anything after that is risking this turbos stability. But I am sure you know it is the cfm that matters, not how many lbs of boost I run.

Depends on how many cubes and how much faster I want to go. Eventually I would have to go to a stage II motor, which can run low 8's.

Can't understand this.

Yes...but not only really fast...but super duper fast...

Guest

Added LCA brackets and that helped. Also have some stickier tires.

Probably my next time out wont be a fair comparison because the car will be lighter by then.

91Bird305

Ah. What tires did you go with? I am a big fan of the M/T drag radials so far.

Juiced01ss

<edited - Let's keep the BS level down - This board is "power adders", not insults. If you're not adding any tech to the discussion, please don't bother posting.>

Guest

Same as you. I may run some slicks next time at the track though... which will probably be in a few months.