305 to 400 My swap log
#202
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Car: 1988 Camaro sport coupe
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Re: 305 to 400 My swap log
Considering pulling the engine out again. Whats the best way to go about doing this while keeping the transmission in. Like should I just disconnect the bolts on the bellhousing to the block and that should be enough for the engine to slide out? I was thinking that wont work because of my 7qt oilpan. Let me know. I reall dont want to have to take out my tranmisison again im tired of that.
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Car: 1987 Iroc Z28/ 1982 Z28
Engine: 355 TPI IP/ 305 CFI
Transmission: T-56/ 300C
Axle/Gears: 3.42 Open/ 3.73 Posi
Re: 305 to 400 My swap log
take the trans off, no way around it without the possibilty of damage.... its not worth breaking **** over an extra hour of work.
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Re: 305 to 400 My swap log
you cant unbolt the trans and slide it back enough to clear the input shaft without practically dropping it anyway. luckily the t5 is a feather weight and its easy to un bolt and drop out of the way. and easy to toss back up and bolt it back in place when the engine is back in.
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Car: 1988 Camaro sport coupe
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Axle/Gears: i think its 3.08 ration posi
Re: 305 to 400 My swap log
Ya the T5 would be easy. But its got a T56 Im just tired of taking my transmission in and out because of all the problems i have had with it. I suppose I will.
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Re: 305 to 400 My swap log
ah, i was going by the info on the left. ive man handled my t56 quite a few times and know how much of a pain it is.
#207
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Axle/Gears: i think its 3.08 ration posi
Re: 305 to 400 My swap log
Im workin on it now. My granpa has my transmission jack so im just undoing the bolts for now. I already have my engine down to a short block, thats why im just going to go ahead and pull the engine out. change the oil pan, I want a 5qt. fix the front oil leak, maybe change both seals. and to properly put the heads back on easier.
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Car: 91 Camaro RS
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Axle/Gears: 3.42 stock posi disc
Re: 305 to 400 My swap log
i wish i had a trans jack. i just used 2 regular jacks to drop it....it takes some effort that way.
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Car: 1988 Camaro sport coupe
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Axle/Gears: i think its 3.08 ration posi
Re: 305 to 400 My swap log
Ya haha the trans jack is the best $80 i spent. I would not want to balance that T56 on some regular jacks and have it fall on my face. I have everything unhooked pretty much. Just waiting on my transjack and all i have to do is take the crossmember off and pull the trans out. all bolts off. all wires unhooked on engine.
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Re: 305 to 400 My swap log
ive had to catch it on more than one occasion. just makes me glad im no weakling. where did you get a trans jack for $80?
#211
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Re: 305 to 400 My swap log
Got it at Harbor Freight, I think it was $80, maybe $90 but I know it was less than a 100
http://www.harborfreight.com/450-lb-...ack-39178.html
http://www.harborfreight.com/450-lb-...ack-39178.html
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Re: 305 to 400 My swap log
i might have to get me one of those. i always seemt o be dropping the trans out of something or another
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Car: 1988 Camaro sport coupe
Engine: 305 TBI
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Axle/Gears: i think its 3.08 ration posi
Re: 305 to 400 My swap log
Engine is out, gonna redo seals, new timing chain cover, new head gaskets, and a 5qt oil pan instead of a 7qt.
#214
Re: 305 to 400 My swap log
Like I suggested.Run a straight edge corner to corner on both the deck and the heads to check to see if anything is warped.A close inspection of the deck from the steam holes to the bolt holes for cracks and look at the exhaust valve seats for the same.
Last edited by 1gary; 11-19-2011 at 04:04 AM.
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Car: 1988 Camaro sport coupe
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Re: 305 to 400 My swap log
ya we checked the heads to see if they were warped. they are fine. Gonna check out the block today
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Re: 305 to 400 My swap log
Scrap the stock heads. <3 my dad. He ordered me a pair of these http://www.jegs.com/i/Edelbrock/350/5089/10002/-1 and yes I will get the steam holes drilled.
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Re: 305 to 400 My swap log
I dont know what it will do the the comperssion. The pistons and crankshaft are stock so im guessing 64cc will raise it right I dont know the math on it? And the heads should be able to support the cam. The max lift on my cam is like .480 and these heads can support upto like .550
#219
Re: 305 to 400 My swap log
Here is a link with a whole bunch of formulas along with one for C/R's.Just plug in the values and it does the math for you.Kind of handy to have and you might want to bookmark it.
http://www.csgnetwork.com/automotiveconverters.html
http://www.csgnetwork.com/automotiveconverters.html
#220
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Car: 1988 Camaro sport coupe
Engine: 305 TBI
Transmission: T5 world class manual transmission
Axle/Gears: i think its 3.08 ration posi
Re: 305 to 400 My swap log
I dont know the deck clearance. The Engine is stock besides cam and heads.
Bore size is 4.125
Stroke is 3.75
Head gasket is 4.2
I dont know what the gasket is compressed but its a .045 thickness gasket.
Combustion chamber is 64cc
Stock 400 piston 12cc ya?
Deck clearance. ????
Bore size is 4.125
Stroke is 3.75
Head gasket is 4.2
I dont know what the gasket is compressed but its a .045 thickness gasket.
Combustion chamber is 64cc
Stock 400 piston 12cc ya?
Deck clearance. ????
#221
Re: 305 to 400 My swap log
I dont know the deck clearance. The Engine is stock besides cam and heads.
Bore size is 4.125
Stroke is 3.75
Head gasket is 4.2
I dont know what the gasket is compressed but its a .045 thickness gasket.
Combustion chamber is 64cc
Stock 400 piston 12cc ya?
Deck clearance. ????
Bore size is 4.125
Stroke is 3.75
Head gasket is 4.2
I dont know what the gasket is compressed but its a .045 thickness gasket.
Combustion chamber is 64cc
Stock 400 piston 12cc ya?
Deck clearance. ????
#222
Re: 305 to 400 My swap log
I have a soft spot for guys that have a limited budget and want to build what they got.That said the Stock rod 400's do have their limits in cam choices and RPM ranges where they can perform safely.Here is a link that explains that better than I can.
http://www.carcraft.com/techarticles...ock/index.html
So given the size of the engine there are guys that think you can cam it up.Really the stock rod deal is more of a torquer engine and not so much a HP deal.Which for street vehicles that is fine.
Also guys think because of the size of the engine they should make a big move in intake runner size and given the stock rod size that isn't the truth.The 180 cc runners are about right because of that.
So while you have it apart you should review the cam choice/RPM range.
The deck ht is 9.025.
Not trying to run up a bill on this build on you,yet you could make a move to a 5.7 rod and oversized .030 piston.A quote from my friend Richard is:
On the pin end of the rod, check for interference of the balance pad with the underside of the piston crown.
On the big end, check for interference with the cam in the area of the rod bolt head and at the pan rail where the oil pan bolts up.
The point is to make you aware of the choices you make.
http://www.carcraft.com/techarticles...ock/index.html
So given the size of the engine there are guys that think you can cam it up.Really the stock rod deal is more of a torquer engine and not so much a HP deal.Which for street vehicles that is fine.
Also guys think because of the size of the engine they should make a big move in intake runner size and given the stock rod size that isn't the truth.The 180 cc runners are about right because of that.
So while you have it apart you should review the cam choice/RPM range.
The deck ht is 9.025.
Not trying to run up a bill on this build on you,yet you could make a move to a 5.7 rod and oversized .030 piston.A quote from my friend Richard is:
On the pin end of the rod, check for interference of the balance pad with the underside of the piston crown.
On the big end, check for interference with the cam in the area of the rod bolt head and at the pan rail where the oil pan bolts up.
The point is to make you aware of the choices you make.
#223
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Re: 305 to 400 My swap log
By rod you mean Push rod right? The rods I have are not stock, they are hardened. I forgot the length though I'll ask my dad tomorrow.
By stock I mean that my engine still has the original crankshaft and pistons and the bore is still stock to. This is the camshaft I have Crane#114142 Compucam and I have all the supporting parts for the cam, Lifters, rocker arms, springs, rods.
Sorry if im wrong on the rods, I'm just learning about the details on this stuff.
By stock I mean that my engine still has the original crankshaft and pistons and the bore is still stock to. This is the camshaft I have Crane#114142 Compucam and I have all the supporting parts for the cam, Lifters, rocker arms, springs, rods.
Sorry if im wrong on the rods, I'm just learning about the details on this stuff.
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Re: 305 to 400 My swap log
or do you mean the rod that connects the piston... lol
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Car: 1987 Iroc Z28/ 1982 Z28
Engine: 355 TPI IP/ 305 CFI
Transmission: T-56/ 300C
Axle/Gears: 3.42 Open/ 3.73 Posi
Re: 305 to 400 My swap log
connecting rod = rods that connect pistons. and hes right, our short rods suck. moving to a 5.7 in rod takes some stress off of cylinder walls and makes for a safer high rev
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Car: 1987 Iroc Z28/ 1982 Z28
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Transmission: T-56/ 300C
Axle/Gears: 3.42 Open/ 3.73 Posi
Re: 305 to 400 My swap log
i invested in an eagle specialties rotating assembly for mine, but thats kinda big bucks
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Car: 1987 Iroc Z28/ 1982 Z28
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Transmission: T-56/ 300C
Axle/Gears: 3.42 Open/ 3.73 Posi
Re: 305 to 400 My swap log
i dont have any problems with them. neither do any of my friends >.>
#229
Re: 305 to 400 My swap log
Honestly I don't want to derail this thread in a debate.I am merely reporting what is a known factor in the trades of building engines and with that I think I have said enough.Suffice to say there are not any "cheap deals" because you surely do get what you pay for.
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Car: 92 camaro R.S.
Engine: 406 Carbed
Transmission: T-400
Axle/Gears: 3.73 limited slip
Re: 305 to 400 My swap log
I dont know the deck clearance. The Engine is stock besides cam and heads.
Bore size is 4.125
Stroke is 3.75
Head gasket is 4.2
I dont know what the gasket is compressed but its a .045 thickness gasket.
Combustion chamber is 64cc
Stock 400 piston 12cc ya?
Deck clearance. ????
Bore size is 4.125
Stroke is 3.75
Head gasket is 4.2
I dont know what the gasket is compressed but its a .045 thickness gasket.
Combustion chamber is 64cc
Stock 400 piston 12cc ya?
Deck clearance. ????
In Car Craft May 2011 they did a 400 SBC rebuild and found that the decks were soooo bad that with a 64 cc head on top of the Huge bore of the standard bore 400, only yielded a compression ratio of 8.5:1 on the best cylinder and as little as 8.39:1 in the lowest cylinder, this is probably where you're gonna be with the NEW HEADS, who knows what you had with your current heads, so you must consider squaring and decking your block, a good flat top or dish piston, and at least a 5.70in. rod, with a 6.00in. being best, I went with the flat top SRP (Sportsman Racing Pistons) and a 6.00in. Rod to take some of the load off the cylinder walls, but I have a touch over 11.5:1 compression, with the Felpro 1014 gaskets (with steam holes) that are .039 compressed thickness, but I don't really know your goals or expectations for your ride, but there is alot of great advise on this site for you, and I hope this is helpful, but my car is not going to be a daily driver but quite streetable for the weekends and cruise nites.
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Car: 92 camaro R.S.
Engine: 406 Carbed
Transmission: T-400
Axle/Gears: 3.73 limited slip
Re: 305 to 400 My swap log
I'll say about ten years ago this was a hot topic, but now their Quality Control is much tighter now, infact I currently use their Rods & Crank in my 1968 Pontiac Firebird racer, and I have no complaints for the last 5-6 years, maybe I'm lucky?
#232
Re: 305 to 400 My swap log
In Car Craft May 2011 they did a 400 SBC rebuild and found that the decks were soooo bad that with a 64 cc head on top of the Huge bore of the standard bore 400, only yielded a compression ratio of 8.5:1 on the best cylinder and as little as 8.39:1 in the lowest cylinder, this is probably where you're gonna be with the NEW HEADS, who knows what you had with your current heads, so you must consider squaring and decking your block, a good flat top or dish piston, and at least a 5.70in. rod, with a 6.00in. being best, I went with the flat top SRP (Sportsman Racing Pistons) and a 6.00in. Rod to take some of the load off the cylinder walls, but I have a touch over 11.5:1 compression, with the Felpro 1014 gaskets (with steam holes) that are .039 compressed thickness, but I don't really know your goals or expectations for your ride, but there is alot of great advise on this site for you, and I hope this is helpful, but my car is not going to be a daily driver but quite streetable for the weekends and cruise nites.
#235
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Car: 1988 Camaro sport coupe
Engine: 305 TBI
Transmission: T5 world class manual transmission
Axle/Gears: i think its 3.08 ration posi
Re: 305 to 400 My swap log
I'm probably going to keep my crank and pistons/rods the way they are it still good for 5500rpm I believe. I'm only 18 with a part time job my dad payed for mostly everything and I don't want to make him spend more than needed.
And really? With my new heads I would only have 8.5:1 compression?
And really? With my new heads I would only have 8.5:1 compression?
Last edited by Cerridius; 11-22-2011 at 02:24 PM.
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Car: 92 camaro R.S.
Engine: 406 Carbed
Transmission: T-400
Axle/Gears: 3.73 limited slip
Re: 305 to 400 My swap log
It may be a little more it may be a little less, but this was the findings in the May 2011 Car Craft article, because the dish style pistons the 400 comes with and the fact that the actual factory deck heights were all over the place on the unmachined block causing compression variances in every cylinder, which goes to show you the importance of a good machinist and exact tolerances, and balancing during assembly to make the most Horse power from your combo, but you'll be more than happy with the power you'll make and have no issues at the Gas pump if you don't go too crazy with ignition timing, so have fun and Happy Holidays.
Last edited by N.J.-SLICK-1; 12-04-2011 at 11:54 AM.
#237
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Car: 1988 Camaro sport coupe
Engine: 305 TBI
Transmission: T5 world class manual transmission
Axle/Gears: i think its 3.08 ration posi
Re: 305 to 400 My swap log
Ya I'm sure with the 6speed and 4.10 gears I will be happy with the hp I have compared to the original 305.
#238
Re: 305 to 400 My swap log
No-no-no.Limited RPM = not a 4.10.I would think torque peaks at 2500 to 3500 and HP peaks at 4500 to 5000(and that estimate might be a shade high).Don't gear this beyond the curves.The one thing to constantly remember is these 400's where built as a smog engine and because of that it does take some cash to turn them around.Capitalize on your set up and tailor your build towards that.You don't have a high RPM engine.You can have somewhat a torquer engine.I think the 24cc piston or the 26cc piston does come into play here.S/C dictates what camming to do and that is why I was wanting you to find the S/C ratio.Makes 0 sense to cam for a high RPM range with your piston/rod/heads,set-up.If you where to 0 deck it,5.7 rods, flat top pistons,195 cc heads,cam it for a higher RPM then with a greater compression ratio.
Just from the days yrs ago where guys like your dad and well me stuck a cam into something and went racing.................that horse left the barn long ago and we have learned how to match things up much better now.
Just from the days yrs ago where guys like your dad and well me stuck a cam into something and went racing.................that horse left the barn long ago and we have learned how to match things up much better now.
#239
Re: 305 to 400 My swap log
Tell you what and I am suggesting here.Never lose sight of any performance vehicle that "you are only as good as the leakiest link".That includes everything from the h/b to the rear wheels.That each level requires you to invest more to have what you expect covered and alittle more.
Example-a guy wants to spray heavy on a cast crank or use a trans brake on a heavy car.That is a grenade with the pin pulled.
Those great deals on "cheap parts" are just what you pay for.Sooooooooo
Example-a guy wants to spray heavy on a cast crank or use a trans brake on a heavy car.That is a grenade with the pin pulled.
Those great deals on "cheap parts" are just what you pay for.Sooooooooo
#240
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Car: 1988 Camaro sport coupe
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Axle/Gears: i think its 3.08 ration posi
Re: 305 to 400 My swap log
The Dad here: Are you saying we should not be upgrading to the 4.10 rear end vs. the 3.08 to match the six speed T-56 Trans? Everyone tells me we will shred the 3.08 in no time. Also, from what I read, to do what you are suggesting we would need to tear the block apart and take it to a machine shop, get it bored out and shave the deck (I guess that is what you mean by 0 decking it) to square it? Then buy new piston rods, pistons, rings, crank bearings etc? With that amount of money and time, I might as well just order a short block already done. If I wanted to do that we would have went with a 350 or 383 crate engine, ready to go. With the $$ we have already invested in this project, I thought I could get better heads to go with the Hydraulic Flat Tappet camshaft, upping to a Holley Avenger 770 cfm carb, and get a bit more oomph than the 882 heads we just drilled out. I guess I could see this more of an issue if we were going to race the car at the track however, it is primarily going to be used as a daily driver. Am I really off the deep end here missing everything or what?
#241
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Car: 91 Camaro RS
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Transmission: Built T-56
Axle/Gears: 3.42 stock posi disc
Re: 305 to 400 My swap log
its not the gears in the car that make the rear week, its the general design of the GM 10 bolt. some say they cant stand up to much power, some have used them successfully behind high hp motors. both the rear with 4.10 gears and the rear with 3.08 gears will withstand the same amount of power if theyre both 10bolts.
what gary is saying is using a 4.10 gear means the engine will spend more time in the higher rpms which you dont wanna do with the set up you have.
what gary is saying is using a 4.10 gear means the engine will spend more time in the higher rpms which you dont wanna do with the set up you have.
#242
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Car: 1988 Camaro sport coupe
Engine: 305 TBI
Transmission: T5 world class manual transmission
Axle/Gears: i think its 3.08 ration posi
Re: 305 to 400 My swap log
The engine will be to high of a RPM even with 6gears?
#243
Re: 305 to 400 My swap log
When I ref .010 down or 0 deck-that is the piston in the bore and the amount of clearance from the top of the piston to the deck surface.Those two in machining are most common and both "should" square the block.One might be used(.010 down) to not have as much compression as 0 deck would.
With what you now know is a torquer engine that you have,you don't want to spin that engine up high.What you want is for it to pull the car threw each torque & HP curve with each gear change and somewhat short shift it.Say as a guess at 4800 RPM.
So here is what I suggest with you engine set-up.3.42's would make that much of a difference for you still allowing the engine to work threw those curves.
About the 10 bolt rear end.Guys have done mod's on them that help,but it is kind of not a complete fix.You can trust in the fact that if you have thoughts of side stepping the clutch peddle at 4 grand the cast crank and the 10 bolt are not going to give you a whole lot of love for the long term.Remember the term you are only as good as the weakest link.
I think you could accept the engine set-up you have now and appreciate it's strengths and weakness working within those refs.
Oh yeah-the days of "crate engines" meaning something have darkened somewhat.I have had two and both surely where not what they are supposed to be.When you build your own,you KNOW what is the build.
With what you now know is a torquer engine that you have,you don't want to spin that engine up high.What you want is for it to pull the car threw each torque & HP curve with each gear change and somewhat short shift it.Say as a guess at 4800 RPM.
So here is what I suggest with you engine set-up.3.42's would make that much of a difference for you still allowing the engine to work threw those curves.
About the 10 bolt rear end.Guys have done mod's on them that help,but it is kind of not a complete fix.You can trust in the fact that if you have thoughts of side stepping the clutch peddle at 4 grand the cast crank and the 10 bolt are not going to give you a whole lot of love for the long term.Remember the term you are only as good as the weakest link.
I think you could accept the engine set-up you have now and appreciate it's strengths and weakness working within those refs.
Oh yeah-the days of "crate engines" meaning something have darkened somewhat.I have had two and both surely where not what they are supposed to be.When you build your own,you KNOW what is the build.
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Axle/Gears: 3.42 stock posi disc
Re: 305 to 400 My swap log
do you have a complete rear with 4.10 gears in it? if so is it posi and have disc brakes? ive got a 3.42 posi disc rear in my car and wouldnt mind doing a stright swap for a taller geared rear.....
#245
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
its not the gears in the car that make the rear week, its the general design of the GM 10 bolt. some say they cant stand up to much power, some have used them successfully behind high hp motors. both the rear with 4.10 gears and the rear with 3.08 gears will withstand the same amount of power if theyre both 10bolts.
I had 4.10 gears in a "built" 10-bolt behind the LS1/T56 in Berlinetta #2. It was fine for the first pass, since I didn't have the RPMs up high enough and the engine bogged. But after the 2nd pass, the gears were toast (although not broken) due to case spread. With a support cover.
With the current 4.11 gears in a 9", with 25" diameter tires, the car turns 1900 RPMs at 65 MPH in 6th gear. Sure, the LS1 is happier with that than a 400 would be, but 1900 RPMs should be a cakewalk with the 400 as well.
#246
Re: 305 to 400 My swap log
That's not really true. The higher number gears multiply the torque being applied by the driveshaft, and actually promote case spread. It'll last longer with 3.08 gears than with 4.10 gears.
I had 4.10 gears in a "built" 10-bolt behind the LS1/T56 in Berlinetta #2. It was fine for the first pass, since I didn't have the RPMs up high enough and the engine bogged. But after the 2nd pass, the gears were toast (although not broken) due to case spread. With a support cover.
With the current 4.11 gears in a 9", with 25" diameter tires, the car turns 1900 RPMs at 65 MPH in 6th gear. Sure, the LS1 is happier with that than a 400 would be, but 1900 RPMs should be a cakewalk with the 400 as well.
I had 4.10 gears in a "built" 10-bolt behind the LS1/T56 in Berlinetta #2. It was fine for the first pass, since I didn't have the RPMs up high enough and the engine bogged. But after the 2nd pass, the gears were toast (although not broken) due to case spread. With a support cover.
With the current 4.11 gears in a 9", with 25" diameter tires, the car turns 1900 RPMs at 65 MPH in 6th gear. Sure, the LS1 is happier with that than a 400 would be, but 1900 RPMs should be a cakewalk with the 400 as well.
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
On the track it would be fine. Driving around town it would be a granny gear.
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Car: 1988 Camaro sport coupe
Engine: 305 TBI
Transmission: T5 world class manual transmission
Axle/Gears: i think its 3.08 ration posi
Re: 305 to 400 My swap log
Dad here again; Got a question on something that is confusing the heck out of me. The casting numbers on our engine are 3951511. Those numbers are for a 70-73; 400; 255-265; 4 bolt mains/HD Truck/Pass. Here is even the link to the castings page: http://www.thedirtforum.com/castings.htm
My issue: I checked and rechecked the casting numbers no less that 20 times and they are 3951511. Trouble is, our engine is a two bolt main when it is supposed to be four bolt. I know the two bolt mains are supposed to be better however, how could this be screwed up? I removed the main caps to make sure someone didn't just put two main caps on there covering the other holes. No such luck, no additional holes. Anyone got any clues????? Here are a couple of pics:
My issue: I checked and rechecked the casting numbers no less that 20 times and they are 3951511. Trouble is, our engine is a two bolt main when it is supposed to be four bolt. I know the two bolt mains are supposed to be better however, how could this be screwed up? I removed the main caps to make sure someone didn't just put two main caps on there covering the other holes. No such luck, no additional holes. Anyone got any clues????? Here are a couple of pics:
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Car: 91 Camaro RS
Engine: empty bay (for now)
Transmission: Built T-56
Axle/Gears: 3.42 stock posi disc
Re: 305 to 400 My swap log
the cost of additional parts needed to change it now wouldnt be worth it.