3rd gen questions

[Dan89rs]

just got my 1st car 89 rs 305 tbi, all stock,but wondering some CHEAP ways to get more performance and fuel milage... i know, i know, if i had the $ id change the above text to: 89 rs 350 stripped of all the computer crap, but i cant afford much. father has 86 t/a, brother 86 iroc-z. we're all kind of wondering if there is such a thing as 'true'-dual on 3rd gens. thanks.

[Morley]

Yes you can run a true dual exhaust on a 3rd gen but it would have to be custom fabricated and would cost $$.
The best starting mods would be a cat back exhaust (3") and headers. Then you'd need to start working on the induction side, K&N air filter, better intake manifold. Then cam, custom chip....

[demon9766]

\0

Originally Posted by Dan89rs

just got my 1st car 89 rs 305 tbi, all stock,but wondering some CHEAP ways to get more performance and fuel milage... i know, i know, if i had the $ id change the above text to: 89 rs 350 stripped of all the computer crap, but i cant afford much. father has 86 t/a, brother 86 iroc-z. we're all kind of wondering if there is such a thing as 'true'-dual on 3rd gens. thanks.

Yes u can put duals on a third gen because i did mine but it is a pain in the a#$ and cost a good bit , unless u know someone with a muffler shop like i do.

[drvngstorm05]

where did u run them? i've seen some guys who ran them right next to the driveshaft... didn't know if there was any other way

[Morley]

Originally Posted by drvngstorm05

where did u run them? i've seen some guys who ran them right next to the driveshaft... didn't know if there was any other way

They run along the stock exhaust routing, side by side, then the mufflers criss-sross at the back of the car using mufflers like this http://store.summitracing.com/defaul...ffler&x=6&y=10 P/N SUM-630622

[92rs25th]

DUal exhaust on a 3rd gen is pointless. Unless you want it for looks and satisfaction. No increase over a 3" single system with a 2 1/2 or even dual 3" system. It actually loses flow which cuases loss of back pressure which causes loss of power. It allows the gas to cool off faster making them slow down. Single 3" system is better for the buck an the bang.

[Morley]

Originally Posted by 92rs25th

It actually loses flow which cuases loss of back pressure which causes loss of power.

Actually, back pressure is what you DON'T want. But you were correct in saying it can cause a loss of flow....You want to keep the VELOCITY of the spent gasses up, which helps scavenge the cylinders.
And, yes a dual 2.5" exhaust will not flow as well as a 3" single. you'd have to be over 400hp to "need" a dual exhaust ovet a 3" single.

[camaronumerouno]

what about side pipes ?

[89IROC&RS]

i have looked into side pipes for the third and fourth gens, you can basicly forget about the big chrome shiney ones from the old vettes, but hit up www.musclemotorsports.com (i think thats the address) they sell used nascar parts. and they have the low profile, large flat sidepipes that nascars use and i have come to the conclusion that with a little work they can fit under the 82-02 camaros. would be damn hot too. inside the car and out

Dual exhausts are doable, but they fall under the catagory of "with enough money, anything is possible." for most Third gen camaros, and most cars on the road to be honest, they arent nessesary. True 3in exhausts are theoreticly only nesseary for an engine making around 700-800hp. a single 3in pipe will handle 400hp well. so until you get to that point, i wouldnt even concider it. My IROC should be pushing 450-500hp, and ill be running a single 3in pipe. and have no reservations about doing so.

as far as gas mileage forget losing the computer, it wil be your best friend in this regard. Focus on combustion efficincy to get better mileage. Look to getting more effective heads with fastburn chambers, I like vortec heads myself, but there are others, SR Torquer 305's, and any other small chamber sbc head. Also get an aftermarket, high power, capasitive discharge ignition system, preferably with multiple spark capibility, match that with a high power coil, a good set of 8mm wires, and youll have much better combustion. Also look to your spark plugs, i am currently looking at new style plugs such as Halo Plugs and E3 plugs due to the larger spark kernel offered by their design, but Bosh +4 plugs or any high performance plug should work just fine.

The cool thing about doing all of these things is that they make the most out of the available fuel and air mixture, which not only give better gas mileage, but also makes more power so youll be killing two birds with one stone.

Depending on how into the engine you want to go, you can also invest in coatings. Anti friction coatings on all bearing, and metal on metal surfaces will reduce friction which wont add power, but will free up that power lost to overcoming rotational resistance. Thermal coatings on piston faces, combustion chambers, and intake/exhaust ports will boost combustion efficiency and make power, and will limit heat transfer to other parts of the engine.

aside from those, the cheap power is limited to stuff outside the engine. a K&N air filter, headers, high flow catback exhaust system, and maybe a higher flow throttle body and intake.