adding torque and accel to an 85'
Thread Starter
Drifting
Joined: Aug 2013
Posts: 1,463
Likes: 0
From: Everett Washington
adding torque and accel to an 85'
my corvette is for leisure getting out here and there and having fun, im no street racer. im the kind of guy that floors it on the on ramps and drives 5-10 mph over. and i love my back roads. so what kind of luck have people had with adding more torque and low to mid range acceleration? im not looking for much top speed here.
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 13
If you have the std 2.59 auto rear then swapping to the factory optional 3.07 gear set can make a major difference
without too much adverse effect on the fuel economy.( depending on your driving style )
http://forums.corvetteforum.com/1568185079-post21.html
without too much adverse effect on the fuel economy.( depending on your driving style )
http://forums.corvetteforum.com/1568185079-post21.html
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
The 85 responds very well to exhaust modifications. If you can't afford headers or they are a problem in Washington then go to the 2-1/2" fron "Y", drop the cat and use a straight thru pipe. You will notice a world of difference. With the stock engine the converter change would help a little. Shift kit would just firm up the shifts and prolong the life of the trans a small amount
Cut the air box over the air filter to get more air into the engine. Leave the stock 48 TB there. It can support up to about 400 HP and your far from that.
Add March under drive pulleys. The engine will spin up a little faster.
1.5 roller rocker arms on the intake valves and 1.6 roller rocker arms on the exhaust will give you a few more HP.
After that......bring out your checkbook. HP Costs money. Your looking at engine modifications at this point. Heads, cam and intake. If you change the cam, you will need to tune the car. Go down to Tom Wong in Vancouver and he will take care of you.
A very good read is to check out Vader86's home page.
Cut the air box over the air filter to get more air into the engine. Leave the stock 48 TB there. It can support up to about 400 HP and your far from that.
Add March under drive pulleys. The engine will spin up a little faster.
1.5 roller rocker arms on the intake valves and 1.6 roller rocker arms on the exhaust will give you a few more HP.
After that......bring out your checkbook. HP Costs money. Your looking at engine modifications at this point. Heads, cam and intake. If you change the cam, you will need to tune the car. Go down to Tom Wong in Vancouver and he will take care of you.
A very good read is to check out Vader86's home page.
Last edited by John A. Marker; Sep 8, 2013 at 01:10 PM.
Thread Starter
Drifting
Joined: Aug 2013
Posts: 1,463
Likes: 0
From: Everett Washington
no emissions at all up here, i was looking for some long tubes, as i recall the emissions are good fore the engine, like the smog and egr is this true or can it all be gutted away?
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
I ran my 85 with the ZZ4 with all emissions equipment attached and running except I pulled the cat to run at the drag strip. Ran 13.2 @107+ multiple times....and that was with AFR low compression (8.5:1) heads.
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Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
You can get a decent gain with the March pulleys. You will see a BIG gain with headers and no cat. The 85 cat bolts in and out, but the pipes "Y" down from the exhaust manifold into a single pipe into the cat and then a reverse "Y" out to the mufflers.
This is what you current exhaust manifold looks like where it joins the "Y" pipe....
Side view...they almost look like a shorty header....pipe not cast iron. There are heat shields over them so unless you have removed them, you don't see the pipe.
I built my own "test pipe" or straight thru pipe to replace the cat when I race....
Good luck with your 85. I will actually be up your direction next week
This is what you current exhaust manifold looks like where it joins the "Y" pipe....
Side view...they almost look like a shorty header....pipe not cast iron. There are heat shields over them so unless you have removed them, you don't see the pipe.
I built my own "test pipe" or straight thru pipe to replace the cat when I race....
Good luck with your 85. I will actually be up your direction next week
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Here is my 85 when it was at Tom Wong's Performance being dyno tuned.
http://www.streetfire.net/video/_2415621.htm
http://www.streetfire.net/video/_2415621.htm
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
About 320 HP and 390 torque at the engine on a Mustang Dyno which is stingy on numbers. I had a dyno done down hear before the ZZ4 and it was showing 350 Hp and 430 torque. The ZZ4 is twice the engine. My son has the 85 in Portland it that car kicks my stock LT1's ***.