TH400 absolutely. Not more expensive but stronger than a TH350.

This will not be a high revver. I'd go 3.42 or 3.73 at most. This motor will go 6,500rpm. With a 27" tire 6,500rpm with 3.73's is 139mph, and there will be a couple of hundred rpm converter slip. You migh be happier with 3.42's and this torque monster.

Rich Krause

 

Alright. How fast would 6,500 rpm with 3.42 be taking you to?

 

About 150 with no slip, but more like 140-145 with slippage. The 3.73's would be in the 130-135 range.

Rich Krause

 

Well thanks a million for all of your help guys. I'll be sure to ask more questions eventually. =)

 

I apologize Rich. I read the quote wrong

What was needed to put that long of a stroke in a 454? What kind of block was it? Do you recall what kind of cam you used?
Since mine will be going in a late model Caprice, I'll need plenty of torque

 

Now that I think of it, it was a 10.200" tall deck truck block. Glad you brought this up. #364776. It has been a long time since I dealt with BBC's or thought about them. These blocks can be found if you look hard enough. They were made until '85.

For a regular 427 or 454 block stick with 4.25" stroke. But if you can find one of the truck blocks (most had 4-bolt mains) they make great street motors.

Rich Krause

 

I'm looking for a tall deck 427. I would trade my stockish 454 shortblock for just a 427T bare block. I think it would be cooler to have 427 badges on my Caprice than 454 badges Then when somebody asks if the badges are true I can show them the block casting numbers to prove it

According to mortec.com http://www.mortec.com/bbc.htm they made the Gen V 427tall deck into the 90s. Ideally I'd like to find a 91+ block so I could say that my car meets all laws for it's age (there's some law saying that if you put a non-stock engine into a vehicle, the design of the engine must be no older than the vehicle.) Plus, a newer block would probably have much less wear on the cylinders.

 

Where would you suggest looking for the 454 tall block?
So if i couldn't find one, and just went with the normal 454... are you still recommending i do the following?

"454 block bored 0.030" over
Scat stroker kit
Edelbrock "Torker II Power Package" "
?
What about the stroke.... 4.25, 4.375, 4.50 ??

 

btw what is the formula you all are using to find the cubic inches?

 

try www.smokemup.com or http://murray.faithweb.com/formulas.htm

 

Awesome. Thanks man.
Rich,
if i can't find a tall block that would mean my best bet would be to go with the 4.25 stroke. You had said something that confused me earlier, you had said 454 blocks have no problem going 60 over, but it would be smarter to go 30 over at first. Wouldn't it make more sense to bore it 60 while you have everything disassembled? Yet then again, what do I know?

 

F-bud: if you start with 30 over, you can later go 40, 50, and then 60 over if needed later. IOW, you will leave three more rebuilds in the block vs. "using it up".

The older short deck blocks have no problem with a 4.25" stroke. So that's an easy "no worry" solution. Larger cranks can be fitted, but the 489ci 4.280x4.25" combo is very easy to get parts for and is plenty big for most people. It will have more rev capability than a longer stroke motor, all else being equal. But for a street motor, if you find a tall deck block, you can make a really dynamite motor using a long stroke.

It just seems that on your budget that the 489 is a good way to go. There is a lot of info out there on the BBC. I have maybe 12-15 books and can recommend some if you like. When contemplating something like this it's nice to have a background knowledge of the different castings (block, heads) before buying any parts. The best way to get into it may be to buy a motor that's already assembled, if the seller is trustworthy and you have someone knowledgable to help you.

The web also has some worthwhile info.

Rich Krause

 

I have been looking on the web, and in fact i printed out a list of all casting numbers and block numbers off mortec.com that i found the other day.
Since I am new to these engines for some reason i was thinking the TH400 was a manual tranny (This is what i have) when it is really auto.
Can anyone recommend a manual trans. that can support say 600 crank hp?
Rich, what were some of those books that you would recommend?
Thanks,
Jason

 

1. Chevrolet Big-Block Interchange Manual by Tom Currao
2. Rebuilding Gen V/Gen VI Big-Block Chevy Engines by Mike Mavrigian
3. How to Build and Modify Chevrolet Big-Block V-8 Engines by Tom Currao
4. How to Build Max Performance Chevy Rat Motors by Ed Staffel

A TH400 is a great choice for a big block. If you insist on clutching your choices are limited if keeping the budget down. The best way is to find a Muncie 4-speed. It's up to big block power levels without a doubt. Stay away form the Saginaw 4-speeds, they aren't as strong. If you want a clutch-type OD transmission, use the T56 but recognize that while it's ok behind a mild big block it won't stand up to a real mountain motor.

If money was no object, then go for a 5-speed Lenco ST1200. Tranny, clutch setup, and shifter oughta run in the $6K range but you won't be breakin it anytime soon.

Rich Krause

 

far as a 4.25 crank in a 454, it isn't just drop it in and forget it...at least not with 6.385 rods. I'm using a CAT 4.25 crank with CAT h-beam rods and the cylinder to rod clearance on the inerside is prety much nule (it will turn but you can barely fit 2 sheets of paper between the big end of the rod and the cylinder). Everything else has enough clearance, just gotta grinde that same spot 8 times. I'm going with the 489 route, using the above with SRP 10-1 pistons, Canfield alum 310cc heads and a comp-cam 288AR solid roller. That combo made 576hp in chevy high perf with oval GM heads and 612hp with GM square heads (all using about 9.5cr). Tq was above 500ftlb from 2500 up and peak power was 5900rpm (I hope I recalled all those numbers correctly )