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Hello to all c3 fans.

I´m a proud owner c3 1981 and i´d like to improve the performances of my vette. I have change the stock chip and the only inprove i´ve obtain is relative to the shifts, because i feel it "changes" faster.
Could you help me how to improve slightly my vette? I´m living in spain and for me is not cheap to ask for parts ( shipment ). If you can help giving me some ways to improve and where can i find them ( i have to order them by internet ).

Thanks a lot and excuses about my redaction !!!! With your help i´m sure to improve it!!!!
My e-mail is: [email protected]
 

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Replacing the stock exhaust is the easiest and most effective single performace mod you can make. A set of headers and true duals, 2.5 inch pipes and free flowing mufflers will improve gas milage and give you a horsepower improvement you can feel in the seat of your pants. God bless, Sensei
 

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sensei said:
Replacing the stock exhaust is the easiest and most effective single performace mod you can make. A set of headers and true duals, 2.5 inch pipes and free flowing mufflers will improve gas milage and give you a horsepower improvement you can feel in the seat of your pants. God bless, Sensei
Thans a lot Sensei !!!
But i have a problem..... here in Spain, we can´t remove the cat to pass the smog inspection. And i think the dual exaust don´t have this ?? Is it true ?

Thanks about your quick answer.
 

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feldespato said:
Thans a lot Sensei !!!
But i have a problem..... here in Spain, we can´t remove the cat to pass the smog inspection. And i think the dual exaust don´t have this ?? Is it true ?

Thanks about your quick answer.
We cannot remove the cat in Illinois either. I plan on replacing my single cat with two free flowing cats. THat way I can get most of the benefits of having a true dual exhaust.
 

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The 81 Vette has a 2.87:1 rear gear ratio on a three speed auto trans that has a fairly week ratio for the first gear. If you really want to wake the car up I would suggest installing 3:73 rear gears, or putting a 700R4 trans in the car. I would suspect you may have a junkyard there with an old GM truck/car that might have a 700R4. You will need to modify your cross member and shorten your driveshaft. The 700 has a super low first gear that will wake that car up. You will think you have another 100 hp under the hood.
 

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The 81 Vette has a 2.87:1 rear gear ratio on a three speed auto trans that has a fairly week ratio for the first gear. If you really want to wake the car up I would suggest installing 3:73 rear gears, or putting a 700R4 trans in the car. I would suspect you may have a junkyard there with an old GM truck/car that might have a 700R4. You will need to modify your cross member and shorten your driveshaft. The 700 has a super low first gear that will wake that car up. You will think you have another 100 hp under the hood.
2end best mode I made. I would also suggest a GM 151 camshaft. That will perk it up.:thumbsup:
 

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the power is in the heads and the cam, exhaust will get you only a small gain.

The 81 only comes w/ 2.87 gears if it has the alu wheels, otherwise it has 2.73s.

You could have a dual system made w/ 2 cat cons, doubt they'd make an issue out of that.

Here's what I built for an 82. it's a full stainless 2.75" dual system w/ dual cats, equal length all the way using a modified (notched) stock crossmember

If you want to really open it up, do away w/ the ECU controlled Q jet and build a proper motor with proper components. The 81 engine is not exactly a performance part.



 

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The '82 catalytic converter is good for 10 HP over the earlier units. You could pick up ten horses and still pass emissions testing.

:thumbsup:
 
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