2.5 Exhaust On A 330HP 327
#21
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Good reading, but more specs than I can relate to. From what I could understand, I'm on the right track using 2.5" pipes with a 330ci, with 330HP engine, but 2.25" could work just as well. Don't know about the size of the crossover, but I would think 1.5" would be OK.
Bob
Bob
Last edited by Factoid; 02-03-2019 at 09:56 AM.
#22
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#23
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Bob, you are absolutely on the right track. When I dropped the LS in my Defender (sourced from a 2012 Camaro), I spent a lot of time researching before buying a bunch of stainless 2.5” straights and mandrel bends and welding up a custom exhaust using a single Magnaflow Tru-X muffler (internal crossover). A non-mandrel bent 90 degree bend reduces flow by up to 25%. Also, saying that larger diameter equals more power is fundamentally flawed. Your exhaust system should be considered as part of your overall engine build. Some engines really benefit from a more restrictive exhaust, pushing the torque band into the most used rpm range and making the car “feel” more powerful. However, an engine with intake, exhaust and cam shaft parameters that can flow X maximum, will not benefit from an exhaust system that can flow 2X. It would also not achieve its potential if the exhaust could only flow .5X.
Great looking exhaust by the way.
Bob
Last edited by 6T2Vette; 02-03-2019 at 10:20 AM.
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Thanks, I loved the sound! On my mutant fat boy build I’m going with a 3” exhaust into a Magnaflow (same muffler, but 3”). With the new rear end set up and no spare tire carrier, I should have just enough room.
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If youre shooting for the original type exh sound no crossover is best but a small H shouldnt alter it much if at all.
#26
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Thanks Factoid. That's one reason I'm thinking that using 2.5" non-mandrel bent pipes might be OK, but if I do go with 2.25 exhaust, I do want it to be a true 2.25" exhaust and not reduced to 2.0" at the bends. I would like an "X" crossover, but I may have to settle for an "H" which will be OK.
Great looking exhaust by the way.
Bob
Great looking exhaust by the way.
Bob
In my opinion the TV show "Engine Masters"...is the MOST informative and ACCURATE engine based show on TV!....Mark
https://www.dailymotion.com/video/x5s8nr8
#28
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Almost NO horsepower gain using either an "X" pipe or "H" pipe vs NO crossover...
In my opinion the TV show "Engine Masters"...is the MOST informative and ACCURATE engine based show on TV!....Mark
https://www.dailymotion.com/video/x5s8nr8
In my opinion the TV show "Engine Masters"...is the MOST informative and ACCURATE engine based show on TV!....Mark
https://www.dailymotion.com/video/x5s8nr8
Me, I'll stay with tradition and go with what I know. I have a '56 Chevy with a 300hp 327 and dual 2,25" "H" type exhaust. I love the 327 BelAir with the throaty sound and excellent response with a 3sp with OD. I also have a '55 Nomad with a 300hp 350 with a 2.5" "X" type exhaust. It has a very mellow sounding exhaust. It has a 700R4 transmission. That's cool too. No one looks at Nomads as hot rods. they both have the same cam, and the same 14" Dynomax Super turbos. The BelAir has the same Rams horns as the Vette. The Nomad has Sanderson shorty headers.
My C1 is different from these two. It has a high 385# torque at 3700rpm, 330hp 327 engine. I wanna sit in this car and when I turn it on, I wanna be reminded it is not my BelAir or my Nomad. Sound, vibration and response are gonna do it for me, and right now the "H" pattern 2.5" is gonna help me get that feeling.
Different strokes for different folks Sidepipe. That's what makes this hobby so diverse and fantastic.
Thanks for your input, I enjoyed the video.
Bob
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#30
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I found it difficult to respond to your post, as you're stating as fact the results of your favorite commercial TV show. That's fine. We're all entitled to our opinion, based on our set of facts.
Me, I'll stay with tradition and go with what I know. I have a '56 Chevy with a 300hp 327 and dual 2,25" "H" type exhaust. I love the 327 BelAir with the throaty sound and excellent response with a 3sp with OD. I also have a '55 Nomad with a 300hp 350 with a 2.5" "X" type exhaust. It has a very mellow sounding exhaust. It has a 700R4 transmission. That's cool too. No one looks at Nomads as hot rods. they both have the same cam, and the same 14" Dynomax Super turbos. The BelAir has the same Rams horns as the Vette. The Nomad has Sanderson shorty headers.
My C1 is different from these two. It has a high 385# torque at 3700rpm, 330hp 327 engine. I wanna sit in this car and when I turn it on, I wanna be reminded it is not my BelAir or my Nomad. Sound, vibration and response are gonna do it for me, and right now the "H" pattern 2.5" is gonna help me get that feeling.
Different strokes for different folks Sidepipe. That's what makes this hobby so diverse and fantastic.
Thanks for your input, I enjoyed the video.
Bob
Me, I'll stay with tradition and go with what I know. I have a '56 Chevy with a 300hp 327 and dual 2,25" "H" type exhaust. I love the 327 BelAir with the throaty sound and excellent response with a 3sp with OD. I also have a '55 Nomad with a 300hp 350 with a 2.5" "X" type exhaust. It has a very mellow sounding exhaust. It has a 700R4 transmission. That's cool too. No one looks at Nomads as hot rods. they both have the same cam, and the same 14" Dynomax Super turbos. The BelAir has the same Rams horns as the Vette. The Nomad has Sanderson shorty headers.
My C1 is different from these two. It has a high 385# torque at 3700rpm, 330hp 327 engine. I wanna sit in this car and when I turn it on, I wanna be reminded it is not my BelAir or my Nomad. Sound, vibration and response are gonna do it for me, and right now the "H" pattern 2.5" is gonna help me get that feeling.
Different strokes for different folks Sidepipe. That's what makes this hobby so diverse and fantastic.
Thanks for your input, I enjoyed the video.
Bob
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6T2Vette (02-04-2019)
#31
Pro
I found it difficult to respond to your post, as you're stating as fact the results of your favorite commercial TV show. That's fine. We're all entitled to our opinion, based on our set of facts.
Me, I'll stay with tradition and go with what I know. I have a '56 Chevy with a 300hp 327 and dual 2,25" "H" type exhaust. I love the 327 BelAir with the throaty sound and excellent response with a 3sp with OD. I also have a '55 Nomad with a 300hp 350 with a 2.5" "X" type exhaust. It has a very mellow sounding exhaust. It has a 700R4 transmission. That's cool too. No one looks at Nomads as hot rods. they both have the same cam, and the same 14" Dynomax Super turbos. The BelAir has the same Rams horns as the Vette. The Nomad has Sanderson shorty headers.
My C1 is different from these two. It has a high 385# torque at 3700rpm, 330hp 327 engine. I wanna sit in this car and when I turn it on, I wanna be reminded it is not my BelAir or my Nomad. Sound, vibration and response are gonna do it for me, and right now the "H" pattern 2.5" is gonna help me get that feeling.
Different strokes for different folks Sidepipe. That's what makes this hobby so diverse and fantastic.
Thanks for your input, I enjoyed the video.
Bob
Me, I'll stay with tradition and go with what I know. I have a '56 Chevy with a 300hp 327 and dual 2,25" "H" type exhaust. I love the 327 BelAir with the throaty sound and excellent response with a 3sp with OD. I also have a '55 Nomad with a 300hp 350 with a 2.5" "X" type exhaust. It has a very mellow sounding exhaust. It has a 700R4 transmission. That's cool too. No one looks at Nomads as hot rods. they both have the same cam, and the same 14" Dynomax Super turbos. The BelAir has the same Rams horns as the Vette. The Nomad has Sanderson shorty headers.
My C1 is different from these two. It has a high 385# torque at 3700rpm, 330hp 327 engine. I wanna sit in this car and when I turn it on, I wanna be reminded it is not my BelAir or my Nomad. Sound, vibration and response are gonna do it for me, and right now the "H" pattern 2.5" is gonna help me get that feeling.
Different strokes for different folks Sidepipe. That's what makes this hobby so diverse and fantastic.
Thanks for your input, I enjoyed the video.
Bob
I built and fabricated a FULL custom exhaust for my 1991 Ferrari Testarossa.....seen/heard at 2:10 & 2:24 of the video...so I'm Not a neophyte at "Custom Exhaust Systems"....Mark
Last edited by sidepipe seeker; 02-03-2019 at 11:35 PM.
#32
The best muffler shop in the Bay Area is, surprisingly, this Meineke shop in Redwood City. Lupe, the owner, is a natural wizard with exhaust systems. I had a hard time believing this at first, because the shop's in a mediocre neighborhood. I couldn't get my Super Turbos to quite fit on my 67 Vette, and neither could other shops, but Lupe got it right. Lupe is a dedicated first-generation Mustang fan but likes all classic cars. He can do anything you want with an exhaust system, he is a perfectionist.
https://www.yelp.com/biz/meineke-car...r-redwood-city
Lou
https://www.yelp.com/biz/meineke-car...r-redwood-city
Lou
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6T2Vette (02-04-2019)
#33
Le Mans Master
Interesting thread. last year, about 3 of my customers bought my chambered mufflers & ended up returning them to me because they could not find a muffler shop that could custom-bend pipe! I can hardly believe this, but it must be true. All I can say is any muffler shop that does not know how to bend pipe & build a system is a ***** - just parts changers. Scary thought that bending exhaust pipes is becoming a lost art.
Also, muffler shop bends are called compression bends, & honestly I do not believe there is very much loss in HP or performance in these vs. mandrel bends. Another couple things discussed were the differences between 2" flowpath & 2.5" flowpath - comments made that there was not much difference. There is actually quite a big difference in flow between these diameters. From 2" to 2.25" alone is quite significant. Between 2.25" & 2.5" there is not a huge difference. Personally on any V-8 exhaust, I would start at 2.25" diameter & use 2.25" or 2.5" diameter up to 485 HP. Beyond that, stepping up to 3" duals can make sense. On the comment of OE C2 sidepipes & systems in 2.5" diameter, still if you cut an OE chambered system open you'll find a MUCH smaller inner diameter of the core - like 1-5/8". Now THOSE are very restrictive!
Also, muffler shop bends are called compression bends, & honestly I do not believe there is very much loss in HP or performance in these vs. mandrel bends. Another couple things discussed were the differences between 2" flowpath & 2.5" flowpath - comments made that there was not much difference. There is actually quite a big difference in flow between these diameters. From 2" to 2.25" alone is quite significant. Between 2.25" & 2.5" there is not a huge difference. Personally on any V-8 exhaust, I would start at 2.25" diameter & use 2.25" or 2.5" diameter up to 485 HP. Beyond that, stepping up to 3" duals can make sense. On the comment of OE C2 sidepipes & systems in 2.5" diameter, still if you cut an OE chambered system open you'll find a MUCH smaller inner diameter of the core - like 1-5/8". Now THOSE are very restrictive!
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6T2Vette (02-04-2019)
#34
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H pipes were never intended for additional horsepower but rather to balance out the exhaust from left and right banks to give a quitter more pleasing sound rather than the back down rap it has without it. Any h.p. gain derived no matter how minimal from it was just a bonus.
Bob
#35
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The reason it's my Favorite Auto TV show is based on the FACTUAL evidence!!...I believe in Dyno numbers that are Replicated from Exacting parameters ....your mileage may vary!...
I built and fabricated a FULL custom exhaust for my 1991 Ferrari Testarossa.....seen/heard at 2:10 & 2:24 of the video...so I'm Not a neophyte at "Custom Exhaust Systems"....Mark
https://www.youtube.com/watch?v=_UQkr_x-Y9k
I built and fabricated a FULL custom exhaust for my 1991 Ferrari Testarossa.....seen/heard at 2:10 & 2:24 of the video...so I'm Not a neophyte at "Custom Exhaust Systems"....Mark
https://www.youtube.com/watch?v=_UQkr_x-Y9k
You should have used your mileage to provide your opinion rather than a critique of your favorite TV show that spent half their time promoting an oil brand and someone's straight through mufflers.
#36
Pro
I'm posting a photo of the FACTUAL evidence provided by a dyno shop of the average of three tests done on my engine. They used headers for the test. I plan to use the original 2.5" manifolds so I'm looking to Replicate or improve the numbers they got.
You should have used your mileage to provide your opinion rather than a critique of your favorite TV show that spent half their time promoting an oil brand and someone's straight through mufflers.
You should have used your mileage to provide your opinion rather than a critique of your favorite TV show that spent half their time promoting an oil brand and someone's straight through mufflers.
Now "if"....you had a dyno printout showing "Your" engine being dynoed for a possible horsepower gain using an "H" pipe...a "X" pipe ...and No pipe....THEN you would have something to compare!...Mark
#37
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jim lockwood (02-04-2019)
#38
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Bob
#39
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I am at a loss to find the correlation of your posting of a dyno printout as it relates to the testing of any gains that the use of an "X" pipe vs an "H" pipe vs No crossover has...
Now "if"....you had a dyno printout showing "Your" engine being dynoed for a possible horsepower gain using an "H" pipe...a "X" pipe ...and No pipe....THEN you would have something to compare!...Mark
Now "if"....you had a dyno printout showing "Your" engine being dynoed for a possible horsepower gain using an "H" pipe...a "X" pipe ...and No pipe....THEN you would have something to compare!...Mark
#40
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Bob
Last edited by 6T2Vette; 02-04-2019 at 02:54 PM.