ok i have an 87 stock everything, from reading various posts an exhaust is the way to go to improve hp. but, do i want full headers back to exhaust tips or just cat back or just pre cats? i`m confused opinions appreciated.

 

long tube headers with high flow cats and a corsa exhaust system is my recommendation, im sure there will be some different opinions, thats just mine.

 

Corsa exhaust will give you nice power, great sound, and almost no drone...

 

120417111943 like this one on ebay?

 

would a 52mm throttle body produce more power if i have a stock plenum?

 

yes, exactly like that one...

 

Throttlebody will give you the POTENTIAL for more power, by allowing you to pull more air into the plenum, but note that the air needs to be pulled in first. This is accomplished by several upgrades, i.e. Heads, intake runners/base, better cam, stroker, etc.

Stock Throttlebody will flow adequate air for stock and mildly enhanced setup. Once your motor has a larger flow requirement, the bigger throttlebody will allow that air to get in, but alone and without enhancements, you will not see any noticeable gains. Put the $300 towards a good cam or some heads first.

Oh, and welcome to the bone stock Vette club :o (I'm also a member)

 

hey, there's nothing wrong with that. you have something to start with and play with it a little at a time.

 

You could probably build a custom dual exhaust system including headers for the price of that cat-back

 

you will get more air in but you will have to put more fuel in it if you do the throttle body. how much money and time do you have to do upgrades?

 

A cheap improvement is to replace the three cat system with a new front y pipe and a single high flow cat. Summit sells these for a little over $200. It will give you better flow and a slightly louder exhaust. You can do the whole thing in an hour if you have access to a lift, or pay some muffler dude to install it for $100 or so. K&M air filter is also supposed to be good for a few hp, and removing the A/C heavy flywheel a few hp as well. One of the members dynoed this combo and saw around a 20 hp increase. My car seemed to have noticably more power after the exhaust change.


I stopped at these three mods. I ordered 1.6 rockers, but there were so many opinions on these that I decided against it and returned them.

Save the old parts in case you decide to sell the car to a pureist.

Also, keep in mind that pure stock is a good thing too. Other than adding a nice catback, most mods are frowned upon if you ever sell the car. I have a 90 convertible and changed the cats to a single cat system. Would I do it again? Probably not, since the louder exhaust gets annoying with the top down at times. It is fine for an hour or so, but after that I sometimes wish I had left it alone. A nice catback would probably cure that, but that will cost around $1k.

The golden formula for horsepower is about $50/additional HP. It ain't cheap.

 

A cheap improvement is to replace the three cat system with a new front y pipe and a single high flow cat. Summit sells these for a little over $200.

Could you give me link to the system you mean on the summit site please?

 

Here ya go..
http://store.summitracing.com/partde...5&autoview=sku

Make sure you spend some time aligning the exhaust so it does not look like a hack job, and so that it does not rattle. View it from the back a few times before you tighten the clamps. Tighten the clams a bit, then take it for a drive around the block and listen for rattles. Double check, then tighten it up for good.

There is nothing worse than driving behind a vette with a crooked exhaust.

I would do this first, and then decide if you need/want a catback. The catbacks bolt up to this ypipe and cat assy, so you can do it at a later date if you so desire.

 

Your stock throttlebody is more than adequate for your motor, even if its modded. Put the money in the exhaust.

 

A big factor in this is the are in which you live. If you have emissions laws you need to keep those in mind. If emissions are of no concern to you then may I suggest long tube headers, dual straight pipes with a X pipe in the middle, and a good set of mufflers. Nice power gain and it will sound awesome.

 

Do not buy an airfoil

 

probably the most useless piece of equipment for the intake. it might work if you had a huge engine sucking in lots of air. but for a stock motor, don't waste the money...