Suggestions for big block swap?

B

Big Block 1974

I'm New Here
You're 5
Nov 14, 2014
2
0
Edmonton
VetteCoins
600
Car
1974 454
Hi. Just found this cool forum. (Hope I'm doing this right).

I am the second owner of a 74 with a numbers matching 454. I've owned it over 20 years, and it's a survivor with 80,000 miles and original paint. But I'm thinking about pulling and wrapping up the engine and tranny, and putting in something with a few more teeth. Any suggestions for out here in the now frozen wasteland of Edmonton? Thanks!
 
Welcome to the forum. Sounds like a nice Corvette you have.

Wish I could offer some sound advice on the motor but I wonder about a GM crate motor, they always seemed to be a good value for the money.

Best of luck with your project.
 
After three summers with a 400 hp LS2 Corvette, I would certainly take a long look at that route. Great power, great gas mileage and docile too. It can be a little expensive and you are dealing with a computer. Still, I'd sure give it a good close look.
 
Transmission

New choices for transmission in these beefed up Borg Warner T10 four speed and five speed transmissions. A few years ago I did up a nice Pontiac 455 powered Lemans Sport with a Borg Warner Super T10. It shifted as nicely as the Muncie M20 and M21 transmissions that I have used over the years. One of these five speeds in an old Musclecar would definitely improve the gas mileage and make the car much more versatile.
SEMA 2014: Motive Gear Brings Back T-10 Transmission In 4 & 5 Speed - Chevy Hardcore
 
700R4 transmissions are a good choice. The early five speed stick shifts were supposed to be weak. A friend took one from a Camaro and put it behind the 396 in his '68 Chevelle. While he doesn't pound the gears but doesn't mind getting on the throttle. After many years, he has had zero problems and gets a fair bit better gas mileage. Today, there are lots of options. With 4.10 gears, I would love to have had a six speed in our musclecars.
 
The '74 big block has what.... about 270 HP ? (380 Torque)
(At least that's what I recall from the early 70's, what GM had to do to meet all the
new-fangled smog requirements).
I had a '74 Olds 455.... it was 250 HP.

Anyway, moving to a newer BB (Crate), or a newer SB (LS2),
you are talking considerably more HP.
The LS2 has 400 HP.

So I really doubt your existing transmission will be able to withstand
any SERIOUS playing.... Burn outs, Drag strip runs, etc.
So, as recommended, a 700R4 is a good choice for a SB... it does have an overdrive.
But for a BB, maybe a 4L80E would be better. It is designed to handle 440 torque.
It also has an overdrive.

If you do go with an LS2, then (as mentioned) you are going to have to
work with a computer, etc., etc.
As far as I am concerned, this is probably too much time, money, etc. to be practical.

Also, what rear gears do you have ? (probably 3.36).
This is another component you might have to look at,
but I think this would still be a good all-round good one.
 
I'm by far no expert so correct me if I am wrong. A 4L60E is, more or less, a modern equivalent to the 700R4 if I remember right and although has some inherent weaknesses that can be overcome with the right internal parts, is a better match for a computer controlled engine if a transmission change is planned IMO. I think the 4L80E, although a stronger transmission, is also larger than the 700R4. I don't know if that will come into play or not but might be something to be aware of.
 
AMS engines in Edmonton does some very good work, I'd just get yours built, then a 700r4 and your good to go, I built a 700r4 for my big block Malibu a few years ago, was very pleased with it, car was around the 3000lb mark, vettes are about the same, the heavy vehicles like trucks is where the 700r4 has issues
 
Big Block 1974 said:
Hi. Just found this cool forum. (Hope I'm doing this right).

I am the second owner of a 74 with a numbers matching 454. I've owned it over 20 years, and it's a survivor with 80,000 miles and original paint. But I'm thinking about pulling and wrapping up the engine and tranny, and putting in something with a few more teeth. Any suggestions for out here in the now frozen wasteland of Edmonton? Thanks!
Click to expand...

Purchase a Big Block from Blue Print engines and install a 4L80E from Jakes. You can thank me later!

Les
 
....my thoughts are to keep those matching numbers in the car. If your need is for more power then why not just add to the existing 454 ? Get the pistons and cam from a 70 and that will give you alot more right there. Everything will look stock. Or next upgrade the intake manifold , factory quadrajets are excellent but a Holley will work too, headers will help abit but can be a road clearance problem . The turbo 400 is a tough tranny so just leave it alone if it's in good shape. Overall mods are minimum and the car will remain near stock looking yet go like a mad man.
Each his own, but once it is altered with tranny swaps, computers , wiring etc . it is a car that loses appeal and value my opinion. When I was searching for one to buy as soon as I seen stuff like that changed I looked the other way no matter how much money was put into it.
Good luck with your project.
 
Old Thread: Hello . There have been no replies in this thread for at least 100 days.
Content in this thread may no longer be relevant.
Perhaps it would be better to start a new thread instead.

Similar threads

Users who are viewing this thread

Total: 1 (members: 0, guests: 1)
Top Bottom