flowmaster merge will get rid of your rasp according to a well known builder on ls1tech.
what muffler or mufflers to use????
- Thread starter lt1z350
- Start date
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Zed 71
Full Access Member
I think it needs more than just a change of mufflers to address the rasp. There are just too many changes in piping diameter and no way to even out the exhaust pulses. Is the flowmaster merge a sort of x-pipe like the magnaflow type?
lt1z350
TYF Newbie
so the 3 inch in dual 2.5 out is what is making it rasp? Well I got the y pipe already that is set up to run duals so that is how I am going with it.Being it will be supercharged here soon I am sure that it will not be over kill on it. I have the smaller american racing long tubes which are 1 and 3/4 and runs to a dual 3 inch y pipe which squeezing the dual 3 inch pipes to one 3 inch probably wasnt the best design and should have been 2.5 dual off headers to the single 3 inch flange.
I dont know how many times I saw people pick up power on older 302 mustangs going to long tubes and bigger exhaust. I was very fortunate to work at a speed shop for years having access to a dyno and doing before and after on all kinds of mods as we had time to play. So a smaller 302 made use of a good dual setup and sounded killer so why cant a larger inch 327 make use of it and sound good? We had a early 79 I beileve come though and it had a factory single exhaust and went to a traditional 2.5 dual off mac long tubes and it picked up mad hp and torque with a b303 cam and stock ported heads now granted the whole setup was barley breaking 300 rwhp there was a good difference over the stuff he had on it.
I feel like the long tubes hurt low end torque right off the bat over the factory manifolds and cats which doesnt make much sense unless the 1 3/4 is just too big for it. Seems to lost some low end but makes up for it up top some. If I wasnt going with boost I would have took the long tubes back off but will need all this soon.
So many mufflers now and so many people saying do this or dont do this. Duals kill it or no it dont I just dynoed mine and it made more power so who to believe????? You cant go off typical old style thinking as these heads flow so much more and design is different so seems same things dont apply as before with thinking a set of inch and 3/4 headers will gain you low end torque but if stuff behind it isnt right then can kill it all anyway.
I saw a chevy high performance mag a while back where they took off gibson shorites and single cat back in favor for kooks long tubes and a kooks dual exhaust set up on a 2002 truck 5.3 I believe and it picked up around 20 to 40 hp and same in torque I believe. I cant find it again to see what exact numbers are. So that right there shows if done right you can see good gains on a NA motor and it was stock with bolt ons. I hope the mess of pipes and merges is hurting it all now and with a good exhaust it will pick torque back up and sound good.
As for the throttle body spacer they not worth the metal made from????? I had it so put it on one of those things but if hurts it I will pull it off. I have a wide band on the truck so have a pretty good tune on it I use tunercat and have messed with it all from trans o the dod stuff to make it stay on longer and hold more under throttle and the truck is getting 16.5 town and up to 20 highway depending on how fast but drive normal around 80 mph I see around 17.5 to 18 as I can hold 4 cyl mode at speed. Being in fl it is pretty flat so easy to hold 4 cyl with how I have it tuned. truck is very similar to Zed 71 but have 3.73 and 275 70 18 on the stock rims.
I know the post is long but tried to break it up into paragraphs for easier reading sorry about the other posts being confusing.
I just was hoping to find someone that has a similar setup and is happy with what they have done I am tired of trial and error and not being happy as I will give up the power now to have it sound good as before spring it will have the cam and magnacharger on it.
I dont know how many times I saw people pick up power on older 302 mustangs going to long tubes and bigger exhaust. I was very fortunate to work at a speed shop for years having access to a dyno and doing before and after on all kinds of mods as we had time to play. So a smaller 302 made use of a good dual setup and sounded killer so why cant a larger inch 327 make use of it and sound good? We had a early 79 I beileve come though and it had a factory single exhaust and went to a traditional 2.5 dual off mac long tubes and it picked up mad hp and torque with a b303 cam and stock ported heads now granted the whole setup was barley breaking 300 rwhp there was a good difference over the stuff he had on it.
I feel like the long tubes hurt low end torque right off the bat over the factory manifolds and cats which doesnt make much sense unless the 1 3/4 is just too big for it. Seems to lost some low end but makes up for it up top some. If I wasnt going with boost I would have took the long tubes back off but will need all this soon.
So many mufflers now and so many people saying do this or dont do this. Duals kill it or no it dont I just dynoed mine and it made more power so who to believe????? You cant go off typical old style thinking as these heads flow so much more and design is different so seems same things dont apply as before with thinking a set of inch and 3/4 headers will gain you low end torque but if stuff behind it isnt right then can kill it all anyway.
I saw a chevy high performance mag a while back where they took off gibson shorites and single cat back in favor for kooks long tubes and a kooks dual exhaust set up on a 2002 truck 5.3 I believe and it picked up around 20 to 40 hp and same in torque I believe. I cant find it again to see what exact numbers are. So that right there shows if done right you can see good gains on a NA motor and it was stock with bolt ons. I hope the mess of pipes and merges is hurting it all now and with a good exhaust it will pick torque back up and sound good.
As for the throttle body spacer they not worth the metal made from????? I had it so put it on one of those things but if hurts it I will pull it off. I have a wide band on the truck so have a pretty good tune on it I use tunercat and have messed with it all from trans o the dod stuff to make it stay on longer and hold more under throttle and the truck is getting 16.5 town and up to 20 highway depending on how fast but drive normal around 80 mph I see around 17.5 to 18 as I can hold 4 cyl mode at speed. Being in fl it is pretty flat so easy to hold 4 cyl with how I have it tuned. truck is very similar to Zed 71 but have 3.73 and 275 70 18 on the stock rims.
I know the post is long but tried to break it up into paragraphs for easier reading sorry about the other posts being confusing.
I just was hoping to find someone that has a similar setup and is happy with what they have done I am tired of trial and error and not being happy as I will give up the power now to have it sound good as before spring it will have the cam and magnacharger on it.
Zed 71
Full Access Member
Y pipe to run duals? Then you are not running a true dual exhaust. Take a picture of what you have.
IMO you need to find a good exhaust and performance shop to help you out. It's all about proper flow from intake to exhaust. Keep in mind long tube headers usually provide more power at higher rpms. As you are experiencing, it's not all about getting the highest numbers; area under the curve and actual use/drivability are important factors.
Honestly did not read your entire post. Need to organize your thoughts. Just saw at the end you want to install a cam and supercharger. That changes things a lot and you should just wait to do everything at once. Hopefully you have a good shop installing this stuff...
IMO you need to find a good exhaust and performance shop to help you out. It's all about proper flow from intake to exhaust. Keep in mind long tube headers usually provide more power at higher rpms. As you are experiencing, it's not all about getting the highest numbers; area under the curve and actual use/drivability are important factors.
Honestly did not read your entire post. Need to organize your thoughts. Just saw at the end you want to install a cam and supercharger. That changes things a lot and you should just wait to do everything at once. Hopefully you have a good shop installing this stuff...
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lt1z350
TYF Newbie
I work at a shop and am a master mechanic transmission rebuilder. I have two 9 second cars a turbo 1992 formula making 620 rwhp on 7 lbs and 820 rwhp at 15 lbs and built the complete kit and tuned myself with using a syclone computer and def code. I was trying to write stuff work and write more and work and didnt read what I was doing and now I have laugh so sorry just trying to do to much at one time here at work.
I had american racing basically take an off road y pipe and not merge it together so left open ended with two pipes. I could have chopped up the y pipe but 400 for a y pipe and they made me what I needed pretty cheap and figured someone could use the y pipe and save some money and being stainless steel cant weld right to it anyway so just had them build that part of it. So I have two pipes running to the passenger side of the truck as if a y pipe but not merged so will run two 2.5 inch pipes off that to either a x pipe then two mufflers or one of the magnaflow tru x mufflers. The tru x sounds like a really good idea as it says it scavenges the gasses and pulls them out rather than pushing so they say on the web site but I cant find a sound clip anywhere or has anyone said they like it and have it so not wanting to throw away another 130 on a muffler I will just dump for 40 bucks like I have the other stuff. My friends vette has ultra flow welded mufflers and a x pipe and sounds pretty good so might go that route with it and if wasnt for the tru x write up I wouldnt even consider it but sounds pretty cool if it actually does what they say.
I have done tons of cars working for more than one speed shop in the past here in jacksonville florida and now work for a small transmission shop building automatics and doing whatever comes through the shop and my prior posts make me sound like on crack so really sorry I shouldnt have tried to think and explain and work at the same time especially walk away then write more going down a different road. I should have started over on this thread and done it now at lunch or at home this evening.
So tru x or not is really the question and you mentioned ditch the throttle body spacer is it just worthless or hurting it? thanks as sorry again for being so missleading and a scatter brain!!!!! lol
I had american racing basically take an off road y pipe and not merge it together so left open ended with two pipes. I could have chopped up the y pipe but 400 for a y pipe and they made me what I needed pretty cheap and figured someone could use the y pipe and save some money and being stainless steel cant weld right to it anyway so just had them build that part of it. So I have two pipes running to the passenger side of the truck as if a y pipe but not merged so will run two 2.5 inch pipes off that to either a x pipe then two mufflers or one of the magnaflow tru x mufflers. The tru x sounds like a really good idea as it says it scavenges the gasses and pulls them out rather than pushing so they say on the web site but I cant find a sound clip anywhere or has anyone said they like it and have it so not wanting to throw away another 130 on a muffler I will just dump for 40 bucks like I have the other stuff. My friends vette has ultra flow welded mufflers and a x pipe and sounds pretty good so might go that route with it and if wasnt for the tru x write up I wouldnt even consider it but sounds pretty cool if it actually does what they say.
I have done tons of cars working for more than one speed shop in the past here in jacksonville florida and now work for a small transmission shop building automatics and doing whatever comes through the shop and my prior posts make me sound like on crack so really sorry I shouldnt have tried to think and explain and work at the same time especially walk away then write more going down a different road. I should have started over on this thread and done it now at lunch or at home this evening.
So tru x or not is really the question and you mentioned ditch the throttle body spacer is it just worthless or hurting it? thanks as sorry again for being so missleading and a scatter brain!!!!! lol
04ctd
Full Access Member
I would like to see some pictures of what all you have, to try to get an idea of what the problem is, and what you have now IN PLACE, and what all parts you have ready to work with.
here is what most folks agree on:
-no crossover sounds sloppy & loud & like you can't afford a good exhaust. alot folks around Kings Bay & Jax sound like that
-you need crossover to even out the exhaust pulses, and to make low end torque.
FWIW, i would run a nice X pipe type of crossover, and I would run the largest (longest) muffler you can fit ( a borla should work )
you want a longer body to absorb more sound
and a Borla is straight through ( just a fancy stainless steel glass pack ) that lets it roar at WOT (because the exhaust isn't impeded on it's way out)
maybe, you could run two sets of mufflers.
like 2 glass packs coming off the collectors, maybe even the tiny bullets.
a lot of guys are using these on there high HP cars on other forums:
http://tl.acurazine.com/forums/showthread.php?t=739889
and put some paragraphs/white space in your typing.
i know how it is to multi-task and try to post something from work
is Flow master not a sponsor on here?
http://www.chevelles.com/forums/showthread.php?t=352829&highlight=install+inside+pipe&page=2
here is what most folks agree on:
-no crossover sounds sloppy & loud & like you can't afford a good exhaust. alot folks around Kings Bay & Jax sound like that
-you need crossover to even out the exhaust pulses, and to make low end torque.
FWIW, i would run a nice X pipe type of crossover, and I would run the largest (longest) muffler you can fit ( a borla should work )
you want a longer body to absorb more sound
and a Borla is straight through ( just a fancy stainless steel glass pack ) that lets it roar at WOT (because the exhaust isn't impeded on it's way out)
maybe, you could run two sets of mufflers.
like 2 glass packs coming off the collectors, maybe even the tiny bullets.
a lot of guys are using these on there high HP cars on other forums:
http://tl.acurazine.com/forums/showthread.php?t=739889
and put some paragraphs/white space in your typing.
i know how it is to multi-task and try to post something from work
is Flow master not a sponsor on here?
http://www.chevelles.com/forums/showthread.php?t=352829&highlight=install+inside+pipe&page=2
