interesting article about log vs el manifolds
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interesting article about log vs el manifolds
Equal length manifold vs log style manifold
video of them swapping manifold, made runs, time lappsed
on the mr2 forum, they said on a modified mr2 turbo, changing the log into a el yield an extra 60 hp on the car
for the guys who are planning to run boost, invest a little in an el, not a log, that's all
video of them swapping manifold, made runs, time lappsed
on the mr2 forum, they said on a modified mr2 turbo, changing the log into a el yield an extra 60 hp on the car
for the guys who are planning to run boost, invest a little in an el, not a log, that's all
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Rep Power: 326 Nice find for some solid proof. Thing is... It's all in the design of both. Looks like they went from a crappy stock log mani, to a high performance equal runner. Some very well designed log manfolds compared to a nice ELR, the results won't be as different. Log manifolds are made for cost and reliability, and for some who just don't have the much room in the engine bay.
Still shows the potential though, I like that...
Still shows the potential though, I like that...
i highly doubt it made that much difference. That is alot but it could be if they were running like 35 lbs of boost, but they are only making 350 hp. Manifolds make a big difference in cars making 1000 hp or more.....aka Supra's, that is big boost, big pressure and alot of heat. But with a MR2? Hmmmm I'll remain skeptical.
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Interesting find..........
Dynapack are noted to have "inflated" power figures because they do not take into account wheel size, tire accomodations and fricton. Not to mention, the entire graph is noted as "flywheel" torque and "flywheel" horsepower. So I'd say maybe after all is said and done (drivetrain loss), maybe 40 WHP & 15 WTQ, which is still a GREAT gain.......then again, like Madwheel stated log style are "cost effectiveness" and reliability. Equal length are geared towards performance and power, but lack reliability because they are more probable to crack.
Dynapack are noted to have "inflated" power figures because they do not take into account wheel size, tire accomodations and fricton. Not to mention, the entire graph is noted as "flywheel" torque and "flywheel" horsepower. So I'd say maybe after all is said and done (drivetrain loss), maybe 40 WHP & 15 WTQ, which is still a GREAT gain.......then again, like Madwheel stated log style are "cost effectiveness" and reliability. Equal length are geared towards performance and power, but lack reliability because they are more probable to crack.
Last edited by dezod; Nov 17, 2004 at 03:39 PM.
hm, on the 1st site listed, it was on a B series turbo motor ... 48whp gained after tuning ... 63 whp gained before tuning.
I don't see in anyway how that is a stock log manifold? I've seen d-series HKS manifolds that look like that ...
I don't see in anyway how that is a stock log manifold? I've seen d-series HKS manifolds that look like that ...
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Originally Posted by Titleist71
i highly doubt it made that much difference. That is alot but it could be if they were running like 35 lbs of boost, but they are only making 350 hp. Manifolds make a big difference in cars making 1000 hp or more.....aka Supra's, that is big boost, big pressure and alot of heat. But with a MR2? Hmmmm I'll remain skeptical.
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The kind of dyno this was performed on has absolutely no relevance to the theory they were trying to prove. They proved that an equal length manifold WILL make more power than a log, all other things being equal.
Originally Posted by opto_isolator
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Originally Posted by Titleist71
i highly doubt it made that much difference. That is alot but it could be if they were running like 35 lbs of boost, but they are only making 350 hp. Manifolds make a big difference in cars making 1000 hp or more.....aka Supra's, that is big boost, big pressure and alot of heat. But with a MR2? Hmmmm I'll remain skeptical.
We (Myself and Mattback) built a car for a customer that wanted 500whp. Specs are as follows:
CP Pistons 9.0:1 CR
Stock Rods w/ ARP rod bolts
ARP Headstuds
Greddy Headgasket
HKS 264 Step 2's
RAS
Greddy valvesprings
Greddy Intake Manifold
Garrett GT3040R Turbo
ROM tune - Z32 MAF, 96# injectors
JGS Tools Log Manifold
HKS Intercooler
When we took it to the dyno for tuning all we could get out of the car at the wastegate pressure of 12.8 psi (0.9 kg/cm^2) was 300whp. I tried different AFR's and timing values but they yeilded no change. The setup simply would not make more than 300whp @ 12.8 psi. This was a problem becasue I knew that we werent going to get to 500whp without running stupid boost...which i didnt want to do. So after alot of head scratching and a few beers to help cope with the disappointment Matt and I compiled a list of everything that was different between this car and my car when it was running a nearly identical setup and making 340hp @ 10 psi.
This is what we came up with:
1) Log manifold vs. Full Race manifold.
2) ROM tune with MAF vs. Haltech on MAP.
At which point we looked across the garage to my car which is currently out of commission and decided we needed to try swapping manifolds. A call to the customer to discuss the situation...and he agreed it was the correct course of action. So the test was on!!
Matt and I worked dilligently friday night after work to get the manifold swapped over. We used my old downpipe and hot pipe of my car. These pieces were nearly identical to the downpipe and hotpipe that were on with the log...just slightly different fitments. We got it up and running, celebrated at Hooters for a late dinner...then headed off to the dyno on saturday morning. I was expeciting to see gains but we were unsure of how much. On satuday morning we ran the car at wastegate pressure (12.8 psi) and after a bit of tuning to get the new setup dialed in we saw the following gains:
All i can say is WOW...60whp and 35ft-lbs. Spoolup was almost identical with the Full Race hitting maybe 100 rpm later. I was completely floored by the results of this test. I was expecting 30-40hp maybe...but 60hp. I was totally shocked.
I think this also disproves the myth that MAF sensors are a restriction. this car made exactly what my setup made at 12 psi with a MAP sensor based system.
The truth of the matter is the flow properties of the LOG manifold are terrible. The flow from 1,2 and 3,4 directly oppose each other then are forced to do a hard 90 deg turn to enter the turbine housing. A basic understanding of fluid dynamics will tell you this is terrible for flow. The smooth transistions of the full race manifold make all the difference allowing the car to make more power even during spoolup!!
Thumbs up to the guys at Full Race for making such a quality product!!
Oh...and the car did 507whp @ 25 psi later that day!!
3) anyone who thinks a long runner merge collector manifold doesnt make power will have a VERY difficult time doing so. Runner length DOES matter, and shorter is certainly not better.
There are a lot of things that go into properly designing and engingeering a manifolds, and rules of them apply VERY rarely.
CP Pistons 9.0:1 CR
Stock Rods w/ ARP rod bolts
ARP Headstuds
Greddy Headgasket
HKS 264 Step 2's
RAS
Greddy valvesprings
Greddy Intake Manifold
Garrett GT3040R Turbo
ROM tune - Z32 MAF, 96# injectors
JGS Tools Log Manifold
HKS Intercooler
When we took it to the dyno for tuning all we could get out of the car at the wastegate pressure of 12.8 psi (0.9 kg/cm^2) was 300whp. I tried different AFR's and timing values but they yeilded no change. The setup simply would not make more than 300whp @ 12.8 psi. This was a problem becasue I knew that we werent going to get to 500whp without running stupid boost...which i didnt want to do. So after alot of head scratching and a few beers to help cope with the disappointment Matt and I compiled a list of everything that was different between this car and my car when it was running a nearly identical setup and making 340hp @ 10 psi.
This is what we came up with:
1) Log manifold vs. Full Race manifold.
2) ROM tune with MAF vs. Haltech on MAP.
At which point we looked across the garage to my car which is currently out of commission and decided we needed to try swapping manifolds. A call to the customer to discuss the situation...and he agreed it was the correct course of action. So the test was on!!
Matt and I worked dilligently friday night after work to get the manifold swapped over. We used my old downpipe and hot pipe of my car. These pieces were nearly identical to the downpipe and hotpipe that were on with the log...just slightly different fitments. We got it up and running, celebrated at Hooters for a late dinner...then headed off to the dyno on saturday morning. I was expeciting to see gains but we were unsure of how much. On satuday morning we ran the car at wastegate pressure (12.8 psi) and after a bit of tuning to get the new setup dialed in we saw the following gains:
All i can say is WOW...60whp and 35ft-lbs. Spoolup was almost identical with the Full Race hitting maybe 100 rpm later. I was completely floored by the results of this test. I was expecting 30-40hp maybe...but 60hp. I was totally shocked.
I think this also disproves the myth that MAF sensors are a restriction. this car made exactly what my setup made at 12 psi with a MAP sensor based system.
The truth of the matter is the flow properties of the LOG manifold are terrible. The flow from 1,2 and 3,4 directly oppose each other then are forced to do a hard 90 deg turn to enter the turbine housing. A basic understanding of fluid dynamics will tell you this is terrible for flow. The smooth transistions of the full race manifold make all the difference allowing the car to make more power even during spoolup!!
Thumbs up to the guys at Full Race for making such a quality product!!
Oh...and the car did 507whp @ 25 psi later that day!!
3) anyone who thinks a long runner merge collector manifold doesnt make power will have a VERY difficult time doing so. Runner length DOES matter, and shorter is certainly not better.
There are a lot of things that go into properly designing and engingeering a manifolds, and rules of them apply VERY rarely.
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Rep Power: 326 When I was referring to the stock manifold... I though beause you pulled this from an MR2 forum, it came of a stock MR2 turbo car, to an upgraded manifold... My b...
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Originally Posted by 4drcivic2k1
The kind of dyno this was performed on has absolutely no relevance to the theory they were trying to prove. They proved that an equal length manifold WILL make more power than a log, all other things being equal.
It should make more power, but that much is an over-statement. That was what I was pointing out.
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Originally Posted by MadWheel
When I was referring to the stock manifold... I though beause you pulled this from an MR2 forum, it came of a stock MR2 turbo car, to an upgraded manifold... My b...
not matter, brawler t3/t4, ko downpipe and a new manifold will take me up to the magical 300 under 20psi, that's all it matters
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Rep Power: 0 They were comparing power gains between a log and a equal length manifold, not the ability of a dyno to measure horsepower. The way the dyno reads is irrelevant. The point of the whole expirement is to prove that an equal length manifold will indeed make more power than a log style. How much is completely variable.
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Originally Posted by 4drcivic2k1
They were comparing power gains between a log and a equal length manifold, not the ability of a dyno to measure horsepower. The way the dyno reads is irrelevant. The point of the whole expirement is to prove that an equal length manifold will indeed make more power than a log style. How much is completely variable.
Not to mention, yes it is VERY variable because each and every engine will not respond the same way to the addition of an EL manifold. The deisgn of the log and the EL will have huge differences as well, not to mention boost pressures being run. An EL on a D17 running 7-8 PSI will not see those gains, maybe, I'd say 10-15 WHP....That is probably pushin it. On the other hand, maybe running 15-20 PSI it will probably make a huge difference.
Also, the gains on how they are measured will definitely skew the stats in a positive or negative fashion. It is the equivalent of me telling you to go measure a box with your foot knowing it's approx 12" versus using a ruler.
A K20 may not respond the same to an EL manifold placed on a 2JZGTE or a 4G63. It SHOULD make more power than a log manifold, but too many variables in the equation can dictate different results.
I am speaking from a statistical standpoint of view & general logic point of view w/ automotive knowledge. Side note: I used to be a professional number chruncher for a living prior to owning Dezod.
Anyway..........back to this thread.
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Rep Power: 0 Agreed but the point of this test was not to determine an exact figure for how much more power you will make, they were trying to prove that an equal length will make more power, and any dyno thats worth anything can show that, be it a mustang, dynojet, or dynapack, etc.
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