I was looking at getting a dual exhaust from mandrelexhaust.com and was wondering should i get 2.25 (thats what i have now, but i have compression bent, well i did but its now destroyed) or should i get 2.5 i dont want to lose all my back pressure.

i got the 2.2 ohv
-Short Ram Intake
-HAD full exhaust, went off roading now i have smashed header
i plan to buy a pacesetter header -------- Should i get 4-1 or 4-2-1???
i also plan to get Comp Cams roller rockers 1.6 ratio, will they fit under my valve cover???
and then my origional question what size exhaust pipe, and what type of muffler will sound best with a dual setup?

My old header,but owell it was a $40 ebay header lol

pick one. it really doesn't matter. your'e not going to lose backpressure lolz

on a side note..............wtf were you doing offroading in a cavalier for?
now granted i kinda wanted to give my car a small lift for awhile but really, y?

you WANT to lose backpressure. you DO NOT want to lose scavenging. two completely different things. N/A ohv will be fine with 2.25.



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Just replace the down pipe and be done.





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NCR-SCCA

Also dual exhaust is going to be a waste on a 4 cylinder, all it will do is add looks and weight. unless your going to build the engine, such as a fully worked head, bigger cam, forged internals with more compression, or plan on going turbo there is no need for anything bigger than 2.25" exhaust on your car.

i'd go with 2.25. 2.5's a waste of money and space.

ok, the reason im replacing the whole thing is that its craply put together and raddles everywhere. the header is a cheap ebay one. so i think ima go with a better header and then get a mandrel 2.25" with borla muffler

2.5 Inch all the way! I had a 2.25 until a few weeks ago. I've been needing and wanting a 2.5 inch for a long time. With my mods, the 2.5 inch mandrel bent system works much better. I don't think back pressure would be an issue if you didn't have enough power to warrant a 2.5 inch on a cavy, but I could be wrong. I can already feel a difference low and top end with this 2.5 inch system. I am getting re-tuned next weekend so we will see just how much WHP it gave me


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With stock internals, stay with 2.25" exhaust. You can't turn enough rpms to necessitate the need for the 2.5" exhaust with proper savaging.

If you really want to upgrade the exhaust, look into a merge collector for the header you have now, with a flex pipe. Cut the crappy ball and socket collector off, get the merge collector welded in place, make the bend and then the flex joint. After that go into a high flow spun cat, a resonator/glass pack(perforated core, not louvered) make the bends to the muffler the a straight through perforated core muffler (Magnaflow, Dynomax UltraFlo, Hooker Maximum Flow, etc...) and the tip of your choice. Whenever possible leave atleast 8" of smooth, straight pipe between bends or components and minimize the severity of the bends(i.e., use two 45-60* bends instead of 90* bends to center up to the center exhaust channel, behind/beneath the firewall.

Zs Z wrote:Also dual exhaust is going to be a waste on a 4 cylinder, all it will do is add looks and weight. unless your going to build the engine, such as a fully worked head, bigger cam, forged internals with more compression, or plan on going turbo there is no need for anything bigger than 2.25" exhaust on your car.

Dual exhaust doesnt really add much weight to make a big difference IMO. You can get a CF hood like me and do the dual exhaust which will basically be just like keeping the same weight with a stock hood. The extra pipe to make it a dual exhaust weighs less than an OEM hood so duals balanced out with a CF hood will still mean less weight than keeping the stock hood. Pretty sweet math equation isnt it? Im running thrush glasspacks on my 2.25" exhaust and LOVE IT. Way better than the Magnaflows. In terms of sound a dual exhaust wont change much.

Why not a pic.

FireRedCav wrote:

Zs Z wrote:Also dual exhaust is going to be a waste on a 4 cylinder, all it will do is add looks and weight. unless your going to build the engine, such as a fully worked head, bigger cam, forged internals with more compression, or plan on going turbo there is no need for anything bigger than 2.25" exhaust on your car.

Dual exhaust doesnt really add much weight to make a big difference IMO. You can get a CF hood like me and do the dual exhaust which will basically be just like keeping the same weight with a stock hood. The extra pipe to make it a dual exhaust weighs less than an OEM hood so duals balanced out with a CF hood will still mean less weight than keeping the stock hood. Pretty sweet math equation isnt it? Im running thrush glasspacks on my 2.25" exhaust and LOVE IT. Way better than the Magnaflows. In terms of sound a dual exhaust wont change much.

Why not a pic.

The duals look nice on your car and for that purpose are great. I was just meaning to say that there is no real performance benefit from it. And when racing every pound counts....but that being said I realize not everyone hits the quarter mile.

FireRedCav, the duals do look good. As for performance, I have to agree, they don't do anything but add weight. If it's for looks, thats fine.

MadJack wrote:FireRedCav, the duals do look good. As for performance, I have to agree, they don't do anything but add weight. If it's for looks, thats fine.

Oh yes I agree with you and Zs Z completely, they do add a tiny bit amount of weight. Just wanted to state if you could drop weight like from an OEM hood to a CF hood then there will be no added weight really.

blucavvy wrote:pick one. it really doesn't matter. your'e not going to lose backpressure lolz

on a side note..............wtf were you doing offroading in a cavalier for?
now granted i kinda wanted to give my car a small lift for awhile but really, y?

well, theres a level c road a few min from my house that is perfect for "rally car driving" but after a few miles it turns into level A and most people wont take tractors up it but i said owell and somehow managed to get my car up it, bottomed out most the way. no oil or tranny leaks yet, but my header got smashed, and my circle tip is now oval lol but as to why i actually did, I truly dont know?

PS: its not realy street racing considering this unmanaged road used like once a year for tractors and the farmers whos land it crosses just luagh there ass off

Im not to worried about weight, i just like the looks of duals, but for a header? what should i get? 4-1 or 4-2-1? what brand?

wow, just realized the first part makes me sound like a complete ricer lol, trust me, im not