pwmin Posted February 23, 2007 Report Share Posted February 23, 2007 i just used a dynomax glass pack cuz it was the only one i could find that was short enough. they can be installed either way. if you have more room just get a thrush or similar and install it backwards. theyll be cheaper than the dynomax and will work fine. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted February 23, 2007 Author Report Share Posted February 23, 2007 How much does the Dynomax resonator quiet it down? Also, does the length of the resonator affect the sound quality and/or the overall loudness of the system? Quote Link to comment Share on other sites More sharing options...
BIGBULS Posted February 23, 2007 Report Share Posted February 23, 2007 Okay that is EXACTLY what I wanted to know- thank you. I think I will go with 2.5" exhaust, don't want too little backpressure, as that is not good also. What??? Ahahahaha. Um, I see that this myth is still being propagated........... ANY backpressure is bad. On an NA engine you DO want high exhaust VELOCITY though to enable ANY scavenging effects at all and to keep low rpm torque intact. On an NA engine.......... On a turbo car, you just want the most posible flow you can get. The turbo itself sits right smack in the middle of your exhaust stream killing ANY possibility of pulse scavenging. The ONLY reason to stay small is to save $$$ (you may not NEED a 3in exhaust, but it will NOT hurt you AND leaves headroom for power increases later), or for fitment reasons. I would point out, on the exhaust side of things, SC engines act like NA ones do (they CAN benefit from proper exhaust sizing)............they move a lot more air though, so for a pair of similar sized engines, one NA , one SC, the SC car should have a larger exhaust. Basically, a 3in probably WON'T hurt yu much at all compared to 2.5in at the boost/flow levels you are talking about.........BUT............if you have ANY plans of going bigger later.......... May as well only do the exhaust ONCE (which is why I also recomended stainless) Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted February 23, 2007 Author Report Share Posted February 23, 2007 Okay that is EXACTLY what I wanted to know- thank you. I think I will go with 2.5" exhaust, don't want too little backpressure, as that is not good also. What??? Ahahahaha. Um, I see that this myth is still being propagated........... ANY backpressure is bad. On an NA engine you DO want high exhaust VELOCITY though to enable ANY scavenging effects at all and to keep low rpm torque intact. On an NA engine.......... On a turbo car, you just want the most posible flow you can get. The turbo itself sits right smack in the middle of your exhaust stream killing ANY possibility of pulse scavenging. The ONLY reason to stay small is to save $$$ (you may not NEED a 3in exhaust, but it will NOT hurt you AND leaves headroom for power increases later), or for fitment reasons. I would point out, on the exhaust side of things, SC engines act like NA ones do (they CAN benefit from proper exhaust sizing)............they move a lot more air though, so for a pair of similar sized engines, one NA , one SC, the SC car should have a larger exhaust. Basically, a 3in probably WON'T hurt yu much at all compared to 2.5in at the boost/flow levels you are talking about.........BUT............if you have ANY plans of going bigger later.......... May as well only do the exhaust ONCE (which is why I also recomended stainless) Okay... well I'm NOT worried about price. I want the best possible exhaust system that I can possibly make and I want it done right. So will running a 3" exhaust hurt ANYTHING in ANY way???? Thanx Quote Link to comment Share on other sites More sharing options...
intern8tion9l Posted February 23, 2007 Report Share Posted February 23, 2007 considering you can just dump the exhaust right after the downpipe, i don't see any way in hell it would hurt you. as stated, after the turbo your exhaust needs zero backpressure. i myself will be going will 3" from the dp back this year. if you're gunna do it, just go for it all at once. no sense changing it down the road. i def don't see all this downsizing throughout the system benefiting you at all Quote Link to comment Share on other sites More sharing options...
z24turbo93 Posted February 23, 2007 Report Share Posted February 23, 2007 my turbo cavalier with open 3 inch downpipe spools up a lot quicker than with full exhaust. One of the first upgrades you see alot of stock turbo cars do is a 3 in downpipe. Hell i think turbo buicks even run 5 inch downpipes as upgrades. The only problem with the turbo grand prix is the turbo. What is the outlet size on the turbo? It doesn't make sense to make a huge exhaust system when the turbo outlet size is only so big atleast i think. 2.5 inch should be sufficient. 3in exhaust is huge compared to 2.5in. If you want to cut down on cost run 3 inch to where the cat is and buy a exhaust cut out and put that where teh cat is. Then run 2.5 the rest of the way back. Thats what i did. Quote Link to comment Share on other sites More sharing options...
89GPSE Posted February 23, 2007 Report Share Posted February 23, 2007 I am planning on doing my exhaust soon also and was wondering, how big of a downpipe can I fit in there? It doesnt look like I have a lot of room to work with. Quote Link to comment Share on other sites More sharing options...
pwmin Posted February 23, 2007 Report Share Posted February 23, 2007 How much does the Dynomax resonator quiet it down? Also, does the length of the resonator affect the sound quality and/or the overall loudness of the system? its still pretty loud, but it was too loud and the exhaust made a funky sound on full throttle. the glasspack cleaned it up. i didnt run it long at all w/o the pack so i cant explain the difference very well except it made it sound a hell of a lot better. the longer the gp, the more quieting material, so the longer, the quiter (generally) Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted February 23, 2007 Author Report Share Posted February 23, 2007 Ok thanks for the info, guys- I will run a 3" exhaust then. How much does the Dynomax resonator quiet it down? Also, does the length of the resonator affect the sound quality and/or the overall loudness of the system? its still pretty loud, but it was too loud and the exhaust made a funky sound on full throttle. the glasspack cleaned it up. i didnt run it long at all w/o the pack so i cant explain the difference very well except it made it sound a hell of a lot better. the longer the gp, the more quieting material, so the longer, the quiter (generally) Alright thats what I thought. I will run a long resonator on there. Does anyone know how big of a downpipe I should/could run? Thanks Quote Link to comment Share on other sites More sharing options...
Nick1234 Posted February 23, 2007 Report Share Posted February 23, 2007 Again what size is the stock dp and how hard is it to get a newer one made. I understand back pressure is bad for a car, but i drove around all summer with this shitty exhaust on the car, and then took everything off from the downpipe back to go to track, and on the way there the car was a complete dog with no exhaust. Even when i added a muffler where the cat was and had the pipe and split in back, the car felt quicker moving around the city. I am also doing my exhuast this year and am not sure what i want to do. I was thinking 2.5 and also thought if i went three, i would still have the bottle neck where the downpipe is. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted February 24, 2007 Author Report Share Posted February 24, 2007 I understand back pressure is bad for a car, but I took everything off from the downpipe back to go to track, and on the way there the car was a complete dog with no exhaust. So there IS a point where too little backpressure is bad... I'm still unsure of what size exhaust to run. Has anyone here ACTUALLY tried a 3" exhaust on their car? I need more info. Thanks Quote Link to comment Share on other sites More sharing options...
Nick1234 Posted February 24, 2007 Report Share Posted February 24, 2007 I understand back pressure is bad for a car, but I took everything off from the downpipe back to go to track, and on the way there the car was a complete dog with no exhaust. So there IS a point where too little backpressure is bad... I'm still unsure of what size exhaust to run. Has anyone here ACTUALLY tried a 3" exhaust on their car? I need more info. Thanks im just speaking from my experience with my car. I heard back pressure was bad aswell. See i took the exhuast off after driving a good 5 months with it. I had my friend in the car and we were on the freeway, and i hit it (on the way to track, just downpipe) and the car barely threw us back. Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted February 24, 2007 Report Share Posted February 24, 2007 I think what hes trying to say is focus on what gives you the most gains. and louder isnt always better. ...you know its factory stainless exhaust???right? not many cars come with that. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted February 24, 2007 Author Report Share Posted February 24, 2007 I'm shooting for good power gains everywhere, not just on top end- thats my goal. ...you know its factory stainless exhaust???right? not many cars come with that. And your point is.....???? Quote Link to comment Share on other sites More sharing options...
BIGBULS Posted February 24, 2007 Report Share Posted February 24, 2007 Look............seriously. A 3in exhaust IS going to do the trick IF it fits (this is the only hurdle *I* see). Period. You'll VERY likely be making over 200whp, and I know of FISTFULLS of other turbo cars that have run 3in exhausts with less power and still had LARGE gains. Hell, while I don't own a TGP, my NX2000 is in the middle of a (forced........due to an 11K rpm excursion) turbo-motor swap. And guess what, if its' little 2.0L (also with a T-25) is getting a 3in and other SR20DET's have been PROVEN to make good power gains with this, I'm pretty sure your 3.1L will also. Both engines WILL be moving similar amounts of air..........a 5500rpm 3.1L vs a 7500rp, 2.0L with the same basic turbo.......... Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted February 24, 2007 Author Report Share Posted February 24, 2007 Look............seriously. A 3in exhaust IS going to do the trick IF it fits (this is the only hurdle *I* see). Period. You'll VERY likely be making over 200whp, and I know of FISTFULLS of other turbo cars that have run 3in exhausts with less power and still had LARGE gains. Hell, while I don't own a TGP, my NX2000 is in the middle of a (forced........due to an 11K rpm excursion) turbo-motor swap. And guess what, if its' little 2.0L (also with a T-25) is getting a 3in and other SR20DET's have been PROVEN to make good power gains with this, I'm pretty sure your 3.1L will also. Both engines WILL be moving similar amounts of air..........a 5500rpm 3.1L vs a 7500rp, 2.0L with the same basic turbo.......... Perfect. That is close enough as far as I'm concerned. 3" it is! I found a thread: http://www.tgpforums.com/index.php?topic=852.0 That told me that the stock DP is only 2.25"! That NEEDS to be made bigger... does anyone with experience here know if I can cut the stock DP, use teh stock flange/mounts/coupler, and as you go further down the DP, I was thinking of cutting it there, and welding a 3" pipe onto there. Could I do this? Also, in that thread, they talk about certain resonators giving too much backpressure, due to their design. Does anyone know of a straight through resonator they recommend running that doesn't have the backpressure problem? Thanks Quote Link to comment Share on other sites More sharing options...
BIGBULS Posted February 24, 2007 Report Share Posted February 24, 2007 Any PERFORATED core, straight-through resonator will work beautifully. In stainless, check out some of the ROUND Dynomax Ultrafow mufflers, also Magnaflow has some nice ones too. Also Borla, Burn's stainless etc. The "bad" resonators are usually the cheaper glasspacks (NON stainless).............Flowtech Red-Hots and Purple Hornies are both louvered core and flow like shit, and I've heard that some of the Cherry-Bombs are too (but others AREN'T). Just look inside............if it's a straight pipe with holes in it, you are gold. Here: Look down inside and you'll see what I mean. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted February 26, 2007 Author Report Share Posted February 26, 2007 Ok cool- I see what you mean. Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted February 26, 2007 Report Share Posted February 26, 2007 I'm shooting for good power gains everywhere, not just on top end- thats my goal. ...you know its factory stainless exhaust???right? not many cars come with that. And your point is.....???? nothin.. just that it aint goin no where. I got a whole nother exhaust for a TGP in the yard if it ever rusts out. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted February 26, 2007 Author Report Share Posted February 26, 2007 Mine's in pretty sad shape and just plain looks like shit. It will look, sound, and perform great when I'm done... you'll see...hehehehe Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted February 26, 2007 Report Share Posted February 26, 2007 nice. soon as the good weather hits I might take out that exhaust out from under the redwoods and upgrade to mandrels and throw it in. I am probably gonna be sick of the too low sounding mufflers that came on my project car. Im not sure but they probably arent the straight through ones. someone just threw on some flowmasters. trying to keep it under $200 for a nice upgrade. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted March 2, 2007 Author Report Share Posted March 2, 2007 Well I'm working on getting together the pieces for this exhaust. I was looking at a Y today: http://www.magnaflow.com/02product/shopexd.asp?zone=main&id=861 What do you guys think? Is that spendy for one of them? Would I be best off running a Magnaflow Y like that, have a custom Y made, or... any suggestions? Thanks Quote Link to comment Share on other sites More sharing options...
mfewtrail Posted March 2, 2007 Report Share Posted March 2, 2007 See my reply @ the other board. BTW, you might want to email the company in that link I gave you to make sure those are stainless(the others of similar price were, but they don't specifically state that on the universal y-pipe I linked you to). Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted March 2, 2007 Author Report Share Posted March 2, 2007 I checked it out and posted a reply on the other board. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted March 4, 2007 Author Report Share Posted March 4, 2007 Anyone know what the dimensions are for the stock mufflers? (length, width, height)? I'm looking at Magnaflow mufflers. http://www.magnaflow.com/02product/02muffler.asp Thanks Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.