Equal length manifold effect on midrange torque
16 June 2002, 02:40 PM
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Puzzled - Stephen Done's UK car with a manifold hauls *** http://dyno.scoobynet.co.uk/uk/stephen_done.htm , but others with VF23 and manifold are disappointed and find that boost threshold increases around 500 RPM.
Theoretically with the more even exhaust gas pulses from equal length the spool up should be improved?
Comments?
Theoretically with the more even exhaust gas pulses from equal length the spool up should be improved?
Comments?
16 June 2002, 08:28 PM
#2
It's a mystery for sure! Any 2 cars with the same mods can perform differently on the road and on the rollers. It could be down to the dyno operator as well...
But why do you need to know John? I thought you had reached you self imposed limit on power/torque to save on potential expensive clutch gear box trouble. Lets face it, if you're going to track this car a lot, then the power you're running must be on the limit of normal reliability (if not passed already), adding to it and something will complain sooner or later.
F (Jimini cricket/profit of doom mode)
But why do you need to know John? I thought you had reached you self imposed limit on power/torque to save on potential expensive clutch gear box trouble. Lets face it, if you're going to track this car a lot, then the power you're running must be on the limit of normal reliability (if not passed already), adding to it and something will complain sooner or later.
F (Jimini cricket/profit of doom mode)
16 June 2002, 08:29 PM
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I'm going for a VF23, manifold with uppipe, replacement clutch and a freer breathing centre and backbox.
Edited to say yes I know I am a ****head
[Edited by john banks - 6/16/2002 8:30:21 PM]
Edited to say yes I know I am a ****head
[Edited by john banks - 6/16/2002 8:30:21 PM]
16 June 2002, 10:14 PM
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John
Don't go down this discussion. In theory, it is due to pulse tuning. Ideally a turbo should be as near to the exhaust valve as possible in order to maiximise the expansion value of exhaust gas as possible. In theory, an inefficient manifold like the Scooby one places two cylinders nearer the turbo giving this effect rather at the expense of the top end. A 4 into one gives better top end breathing, but means that the exhuast pulse effect is lost due to longer and greater diameter tubing for the nearest cylinders. In practice, it is all down to the mapping and boost control rather than these theories. Hence some people lose mid range power, otherds gain throughout the range.
HTH
Duncan
Don't go down this discussion. In theory, it is due to pulse tuning. Ideally a turbo should be as near to the exhaust valve as possible in order to maiximise the expansion value of exhaust gas as possible. In theory, an inefficient manifold like the Scooby one places two cylinders nearer the turbo giving this effect rather at the expense of the top end. A 4 into one gives better top end breathing, but means that the exhuast pulse effect is lost due to longer and greater diameter tubing for the nearest cylinders. In practice, it is all down to the mapping and boost control rather than these theories. Hence some people lose mid range power, otherds gain throughout the range.
HTH
Duncan
16 June 2002, 11:41 PM
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To be honest with you, there are hardly any performance benifits from modifying the header pipes. Apart from the weight the standard manifold is very efficent
Equal length pipe do not really take into account the pulse factors, you need to get a tuned length pipe for this to work.
Your get the most gains by port matching the exhaust ports with the header pipes.
Equal length pipe do not really take into account the pulse factors, you need to get a tuned length pipe for this to work.
Your get the most gains by port matching the exhaust ports with the header pipes.
18 June 2002, 12:42 AM
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I want to defend my manifold !!! If equal length manifolds never work, how do you explain me getting 312 lbft at around 3000 RPM with 17PSI boost on a standard turbo and intercooler in March ?
btw, my manifold is a Maxim Racing Manifold on a 99MY. Pipes are all the same length and CSA. Pipes are actually pretty narrow compared with OEM. This would make the manifold resonate at a lower frequency for a given pipe length. Maybe this would limit ultimate top end power, but I'm only on a baby turbo.
I think we are generalising somewhat. Some manifolds don't work, and some definitely do. To me, it's like saying turbos don't work - they have different characteristics.
Does anyone have a Maxim Racing / Power Manifold and think it doesn't work ?
Having said that, Merv & I got 2 crates of Stella for recommending taking a manifold off last week after we couldn't get any bottom end power out of the car. We were convinced that there was something amiss, and went so far as to swap the entire exhaust (thought the CAT was blocked), MAF, air filter & ECU to eliminate other areas, since the turbo just wouldn't spool anything like it should, no matter what we did to the fuelling, ignition or boost control.
Submannz: Which manifold didn't work in your experience ?
Anyone have any recommendations of manifolds they like. It would be good to know their relative benefits.
Some manifolds are non-equal length and not tuned. Some are equal length and tuned. Some are both. The tuned frequency of a pipe is based on its length and internal CSA. This means you can have two pipes of differing lengths that have the same resonant frequency because their CSA is different. This means that in theory you can make a tuned manifold in the same rough shape as the OEM design (2 short, 2 long) but tuned. I think some manufacturers do this - is it HKS possibly ?
>Any 2 cars with the same mods can perform differently
>on the road and on the rollers
>
Much of this can be attributed to different ECU maps on cars with OEM ECUs.
>Apart from the weight the standard manifold is very efficent
>
At absorbing noise maybe. I didn't make this graph up ;-)
http://www.steve.ukmail.org/car/torque.gif
Red to green is purely manifold.
Also bear in mind ambient temp was higher when the manifold was tested. Everything else, including fuel was the same.
Cheers
Steve
P.S. My car and the troublesome one were both mapped by the same people (Mervyn and I) with dramatically different outcomes. My point is, this difference was not down to differing mapping abilities. If anything we would have had more experience on this car, unless senility is setting in of course ;-) Same rollers too. The list of variables is narrowing !
(Edited in response to BugEyed, Floyd & Neal)
[Edited by StephenDone - 6/18/2002 10:17:32 AM]
btw, my manifold is a Maxim Racing Manifold on a 99MY. Pipes are all the same length and CSA. Pipes are actually pretty narrow compared with OEM. This would make the manifold resonate at a lower frequency for a given pipe length. Maybe this would limit ultimate top end power, but I'm only on a baby turbo.
I think we are generalising somewhat. Some manifolds don't work, and some definitely do. To me, it's like saying turbos don't work - they have different characteristics.
Does anyone have a Maxim Racing / Power Manifold and think it doesn't work ?
Having said that, Merv & I got 2 crates of Stella for recommending taking a manifold off last week after we couldn't get any bottom end power out of the car. We were convinced that there was something amiss, and went so far as to swap the entire exhaust (thought the CAT was blocked), MAF, air filter & ECU to eliminate other areas, since the turbo just wouldn't spool anything like it should, no matter what we did to the fuelling, ignition or boost control.
Submannz: Which manifold didn't work in your experience ?
Anyone have any recommendations of manifolds they like. It would be good to know their relative benefits.
Some manifolds are non-equal length and not tuned. Some are equal length and tuned. Some are both. The tuned frequency of a pipe is based on its length and internal CSA. This means you can have two pipes of differing lengths that have the same resonant frequency because their CSA is different. This means that in theory you can make a tuned manifold in the same rough shape as the OEM design (2 short, 2 long) but tuned. I think some manufacturers do this - is it HKS possibly ?
>Any 2 cars with the same mods can perform differently
>on the road and on the rollers
>
Much of this can be attributed to different ECU maps on cars with OEM ECUs.
>Apart from the weight the standard manifold is very efficent
>
At absorbing noise maybe. I didn't make this graph up ;-)
http://www.steve.ukmail.org/car/torque.gif
Red to green is purely manifold.
Also bear in mind ambient temp was higher when the manifold was tested. Everything else, including fuel was the same.
Cheers
Steve
P.S. My car and the troublesome one were both mapped by the same people (Mervyn and I) with dramatically different outcomes. My point is, this difference was not down to differing mapping abilities. If anything we would have had more experience on this car, unless senility is setting in of course ;-) Same rollers too. The list of variables is narrowing !
(Edited in response to BugEyed, Floyd & Neal)
[Edited by StephenDone - 6/18/2002 10:17:32 AM]
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18 June 2002, 09:18 AM
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Are there any photos of the various header designs?
Check out www.tezet.ch and then click on 'Aktuelles'. The price is good (£766 with up-pipe), but I'm not sure of the design.....
Thanks
Richard
[Edited by dowser - 6/18/2002 10:19:35 AM]
Check out www.tezet.ch and then click on 'Aktuelles'. The price is good (£766 with up-pipe), but I'm not sure of the design.....
Thanks
Richard
[Edited by dowser - 6/18/2002 10:19:35 AM]
18 June 2002, 09:55 AM
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I am not particularly happy that this is being discussed on an open forum but as it now is......Stephen, I think careful consideration is needed before conclusions are drawn, I am prepared to discuss this in more detail but offline, not here.
Just for the record the manifold was on my car, a UK MY00. Currently it has an ITG, SS d/p, standard mid-cat and standard BB plus a TEK2.
PE did not remove the manifold. The beer was bought in recognition of all the after hours work both Stephen and Merv did on my car.
When first fitted (SS d/p, 802 ECU, ITG) the manifold showed midrange gains up to 25 ftlb of torque at PE when compared to a similar UK car without manifold.
With the TEK2 the car did not show the low down gains expected. Stephen and Merv worked very hard (for which I am still grateful) to improve torque but to no avail, the recommendation was to remove the manifold and re-test.
I now have a ported OEM manifold on the car, pickup below 3K is improved but peak power is a little less than before (given that the RR run was on a different day, it is difficult to be 100% accurate) and turbo spool up, IMHO, it still not right.
I would like people to consider that the UK car has a small TD04 turbo which maybe part of the problem and also that my car has never produced a lot of power, even with a d/p, TEK2, de-cat center and PE back box the figures are not outstanding.
To draw a conclusion that it must part/product 'X' as responsible on a test sample of one is not very valid.
Let's see how John gets on and take it from there.
Neal
Just for the record the manifold was on my car, a UK MY00. Currently it has an ITG, SS d/p, standard mid-cat and standard BB plus a TEK2.
PE did not remove the manifold. The beer was bought in recognition of all the after hours work both Stephen and Merv did on my car.
When first fitted (SS d/p, 802 ECU, ITG) the manifold showed midrange gains up to 25 ftlb of torque at PE when compared to a similar UK car without manifold.
With the TEK2 the car did not show the low down gains expected. Stephen and Merv worked very hard (for which I am still grateful) to improve torque but to no avail, the recommendation was to remove the manifold and re-test.
I now have a ported OEM manifold on the car, pickup below 3K is improved but peak power is a little less than before (given that the RR run was on a different day, it is difficult to be 100% accurate) and turbo spool up, IMHO, it still not right.
I would like people to consider that the UK car has a small TD04 turbo which maybe part of the problem and also that my car has never produced a lot of power, even with a d/p, TEK2, de-cat center and PE back box the figures are not outstanding.
To draw a conclusion that it must part/product 'X' as responsible on a test sample of one is not very valid.
Let's see how John gets on and take it from there.
Neal
18 June 2002, 09:58 AM
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Here are the piccies to compare side by side.
#1 http://www.tezet.ch/aktuell/subaru.jpg
#2 http://www.steve.ukmail.org/car/powermanifold2.jpg
#1 is non equal length with larger diameter pipes from what I can see. Also seperate manifold and up pipe - easy to fit. Design is 4 into 1.
#2 is equal length. Pipes appear smaller diameter, difficult to tell though. Up pipe and manifold are combined - a bitch to fit. Design is 4 into 2 into 1.
Does anyone have a nice HKS piccy we can compare too ?
Steve
#1 http://www.tezet.ch/aktuell/subaru.jpg
#2 http://www.steve.ukmail.org/car/powermanifold2.jpg
#1 is non equal length with larger diameter pipes from what I can see. Also seperate manifold and up pipe - easy to fit. Design is 4 into 1.
#2 is equal length. Pipes appear smaller diameter, difficult to tell though. Up pipe and manifold are combined - a bitch to fit. Design is 4 into 2 into 1.
Does anyone have a nice HKS piccy we can compare too ?
Steve
18 June 2002, 10:04 AM
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It has been said before many times, that equal length manifolds are designed specifically to improve normally aspirated (and mechanically supercharged actually) cars.
The tuned length idea is much better, and has some merits on turbo charged cars.
I have seen vastly different outcomes from several types of headers, and am also convinced it comes down to mapping.
Every make of headers I have seen (eventually) produced better results than standard, but in some cases it took a lot of work.
Anders headers have been suffering so far, but I think the leaking issue needs to be resolved before anyone can comment.
When approaching 350+bhp you really need to consider changing headers as the standard ones, and most notably the up pipe start to look a little restrictive.
Saying that my old mrt headers formerly belonging to R19KET, and before that Firefox, and now Moray Mackenzie were not much larger diameter wise than standard to the point that some people right them off based on their appearance, but when on the car, the difference was phenominal.
In Marks car, no apparent loss in spool up, no loss in low down torque, and 25% extra fuel required at the top end. The car was not slow before, but with four fat *******s in it, it was pulling harder, than a very hard pulling thing.
The tuned length idea is much better, and has some merits on turbo charged cars.
I have seen vastly different outcomes from several types of headers, and am also convinced it comes down to mapping.
Every make of headers I have seen (eventually) produced better results than standard, but in some cases it took a lot of work.
Anders headers have been suffering so far, but I think the leaking issue needs to be resolved before anyone can comment.
When approaching 350+bhp you really need to consider changing headers as the standard ones, and most notably the up pipe start to look a little restrictive.
Saying that my old mrt headers formerly belonging to R19KET, and before that Firefox, and now Moray Mackenzie were not much larger diameter wise than standard to the point that some people right them off based on their appearance, but when on the car, the difference was phenominal.
In Marks car, no apparent loss in spool up, no loss in low down torque, and 25% extra fuel required at the top end. The car was not slow before, but with four fat *******s in it, it was pulling harder, than a very hard pulling thing.
18 June 2002, 10:10 AM
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Hi Neal,
Sorry if you aren't happy about this. I wasn't going to mention any manufacturers or names - I wanted to the thread to remain more abstract than this. I'll remove my posting if you like. My point wasn't about your make of manifold, only that their effect and designs can vary significantly. If I have some of the details wrong, apolgies. I assumed PE removed it - we spent 'til midnight experimenting with other aspects of the car and when I spoke to Mervyn later that week, he said the manifold had been removed - I assumed by PE.
John perhaps you can remove your post ?
Just to let you know my situation too. I work closely with David Power and Mervyn Carroll on EcuTek. This business has no financial relations to Power Engineering - we just use their dyno when it's free, and have an office in the same building - just like London Superchips. I bought my manifold before I knew the guys any better than anyone else on the BBS and paid full price. I have no incentive to plug my manifold other than the fact that I think it's great.
Cheers
Steve
Sorry if you aren't happy about this. I wasn't going to mention any manufacturers or names - I wanted to the thread to remain more abstract than this. I'll remove my posting if you like. My point wasn't about your make of manifold, only that their effect and designs can vary significantly. If I have some of the details wrong, apolgies. I assumed PE removed it - we spent 'til midnight experimenting with other aspects of the car and when I spoke to Mervyn later that week, he said the manifold had been removed - I assumed by PE.
John perhaps you can remove your post ?
Just to let you know my situation too. I work closely with David Power and Mervyn Carroll on EcuTek. This business has no financial relations to Power Engineering - we just use their dyno when it's free, and have an office in the same building - just like London Superchips. I bought my manifold before I knew the guys any better than anyone else on the BBS and paid full price. I have no incentive to plug my manifold other than the fact that I think it's great.
Cheers
Steve
18 June 2002, 10:23 AM
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Neal,
Apologies for my flippant remark. I agree with you though - no conclusions can be drawn from this single case. There are many factors affecting the results from intake all the way through to exhaust. What works for one with a pod filter will do bugger all for someone with the standard airbox/resonator if the induction differences are affecting the exhaust gas flow at a critical point.
Adam - I don't understand the difference between 'equal length' and 'tuned length', surely the former is an example of the latter?
I think the only way to truly find the merit of a design is fit one to your car.....or try somebody else's with the same mods
Richard
Apologies for my flippant remark. I agree with you though - no conclusions can be drawn from this single case. There are many factors affecting the results from intake all the way through to exhaust. What works for one with a pod filter will do bugger all for someone with the standard airbox/resonator if the induction differences are affecting the exhaust gas flow at a critical point.
Adam - I don't understand the difference between 'equal length' and 'tuned length', surely the former is an example of the latter?
I think the only way to truly find the merit of a design is fit one to your car.....or try somebody else's with the same mods
Richard
18 June 2002, 10:40 AM
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Stephen,
No problem. No need to delete any posts. If I had bought different manifolds the story may have been a happy one but I am starting to think that you and Merv where fighting against something else with my car and it's not the manifold in it's self causing the problem.
PS I hope to be at PE on the 30th and would look forward to talking to you then if there's time.
Neal
No problem. No need to delete any posts. If I had bought different manifolds the story may have been a happy one but I am starting to think that you and Merv where fighting against something else with my car and it's not the manifold in it's self causing the problem.
PS I hope to be at PE on the 30th and would look forward to talking to you then if there's time.
Neal
18 June 2002, 11:13 AM
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Thanks Christian,
What are the brackets in the middle of the long pipes for? What difference did it make, and did you require a remap to get the best from it?
Doesn't look so different to Tezet's offering except for the short pipe's bend radius. Hmmmmm - more money....maybe....later
Richard
What are the brackets in the middle of the long pipes for? What difference did it make, and did you require a remap to get the best from it?
Doesn't look so different to Tezet's offering except for the short pipe's bend radius. Hmmmmm - more money....maybe....later
Richard
18 June 2002, 11:21 AM
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Some background stuff here, for anyone who's bored with what they're doing at the moment, although note that this is for normally aspirated engines, which as Adam keeps pointing out, have quite different needs! Useful 'background' stuff, though.
18 June 2002, 11:22 AM
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Hi Neal,
We'll definitely have a chat on the Sunday. I'll be there even if England are in the final. Mervyn'll be in another heap of Stella cans :-) We can always setup the projector to watch the match rather than DeltaDash !
I think my manifold suits my setup, since it is tuned to low revs and this accentuates the early spool up of the little td04 turbo. Your manifold is larger bore and may be freer flowing at the top end than mine. Maybe this will suit John's vf23 very well, since his torque will be further right anyway.
>If I had bought different manifolds the story may have been a
>happy one but I am starting to think that you and Merv where
>fighting against something else with my car and it's not the
>manifold in it's self causing the problem.
>
Well, that's what we thought. We changed everything else, since we didn't think it would be the manifold - everything that came off quickly with a spanner ! On the ECU side, we filled in the fuelling and checked on the Exhaust gas analyser to give good AFR on spool up. We also advanced the ignition in increments at low revs and held the wastegate shut on spool up, but nothing made it spool how we had expected.
John: I hope you've saved lots of cash for all those incremental dyno runs ! We all want to see how it goes.
ChristianR: That HKS looks nice. I think I need to get whatever digital camera you have - mine never come out like that ! So that's another 4 into 1, unequal length one then. Do you have any before/after dyno runs ?
Steve
We'll definitely have a chat on the Sunday. I'll be there even if England are in the final. Mervyn'll be in another heap of Stella cans :-) We can always setup the projector to watch the match rather than DeltaDash !
I think my manifold suits my setup, since it is tuned to low revs and this accentuates the early spool up of the little td04 turbo. Your manifold is larger bore and may be freer flowing at the top end than mine. Maybe this will suit John's vf23 very well, since his torque will be further right anyway.
>If I had bought different manifolds the story may have been a
>happy one but I am starting to think that you and Merv where
>fighting against something else with my car and it's not the
>manifold in it's self causing the problem.
>
Well, that's what we thought. We changed everything else, since we didn't think it would be the manifold - everything that came off quickly with a spanner ! On the ECU side, we filled in the fuelling and checked on the Exhaust gas analyser to give good AFR on spool up. We also advanced the ignition in increments at low revs and held the wastegate shut on spool up, but nothing made it spool how we had expected.
John: I hope you've saved lots of cash for all those incremental dyno runs ! We all want to see how it goes.
ChristianR: That HKS looks nice. I think I need to get whatever digital camera you have - mine never come out like that ! So that's another 4 into 1, unequal length one then. Do you have any before/after dyno runs ?
Steve
18 June 2002, 11:24 AM
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Referring to Dowser's post - I can do the brackets bit - they're for expansion. It gets hot down there
I think it's quite different to the Texet (?) one - although tricky to tell from the picture! Different geometry & therefore lengths, etc. & it's almost impossible to get any idea of diameters... but both obviously follow the 'non equal-length' path.
[Edited by nom - 6/18/2002 11:30:32 AM]
I think it's quite different to the Texet (?) one - although tricky to tell from the picture! Different geometry & therefore lengths, etc. & it's almost impossible to get any idea of diameters... but both obviously follow the 'non equal-length' path.
[Edited by nom - 6/18/2002 11:30:32 AM]
18 June 2002, 11:28 AM
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Just looking at Neal's set up again - wouldn't having a standard & so highly-restrictive BB in the exhaust line cause the manifold to have little effect, as any extra exhaust-flow 'ability' of the new manifold would be queued back because the BB would slow it all up? In other words, it can't do it's main job of getting the gases through it quickly 'cos there's a block further down the line? Or am I being a bit of a thicky here
[Edited by nom - 6/18/2002 11:30:47 AM]
[Edited by nom - 6/18/2002 11:30:47 AM]
18 June 2002, 12:11 PM
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I have no problem with people knowing that Neil was using one of our manifolds.
It is the only UK spec car that I knew to be using one and Neil bought it second hand from someone who liked it, but preferred the standard burble noise on his P1.
The exact same design was fitted to Anders car and this is one quick 22B. As is Nicky Grist's, in almost identical format. 375+lb is a lot of torque. The same design is fitted to Phil Gardner's Type R. This produced so much torque during mapping for the manifold, that the mapping session had to be abandoned until a stronger clutch was fitted.
I also had the same fitted to my RA. No one is going to say that that car doesn't have some serious grunt.
The pipe lengths are all between 29" and 30". About as close as you can get. Some "equal" length manifolds have 6" between pipe lengths.
I know that Neil was dissapointed to take his off and is probably more dissapointed now that he has found that the car still isn't right without it. A full straight through exhaust is a must with these. So is specific mapping.
Any manifold will have a sweet spot in the rev range, which is where its length is most effective in its "tuned" effect. Our manifold has this sweet spot between 4,000 and 5,500rpm. Either side, it is still effective, but the gains are less noticeable. The same is true for any manifold, equal length or not but the sweet spot will be in a different place.
The 01 car has its lambda sensor in the manifold, so fitting an equal length would mean you could only sample gas from 1 or 2 cylinders. You could move the lambda to behind the turbo, but I have no experience of the side effects, using the latest lambda sensor.
It is the only UK spec car that I knew to be using one and Neil bought it second hand from someone who liked it, but preferred the standard burble noise on his P1.
The exact same design was fitted to Anders car and this is one quick 22B. As is Nicky Grist's, in almost identical format. 375+lb is a lot of torque. The same design is fitted to Phil Gardner's Type R. This produced so much torque during mapping for the manifold, that the mapping session had to be abandoned until a stronger clutch was fitted.
I also had the same fitted to my RA. No one is going to say that that car doesn't have some serious grunt.
The pipe lengths are all between 29" and 30". About as close as you can get. Some "equal" length manifolds have 6" between pipe lengths.
I know that Neil was dissapointed to take his off and is probably more dissapointed now that he has found that the car still isn't right without it. A full straight through exhaust is a must with these. So is specific mapping.
Any manifold will have a sweet spot in the rev range, which is where its length is most effective in its "tuned" effect. Our manifold has this sweet spot between 4,000 and 5,500rpm. Either side, it is still effective, but the gains are less noticeable. The same is true for any manifold, equal length or not but the sweet spot will be in a different place.
The 01 car has its lambda sensor in the manifold, so fitting an equal length would mean you could only sample gas from 1 or 2 cylinders. You could move the lambda to behind the turbo, but I have no experience of the side effects, using the latest lambda sensor.
18 June 2002, 01:17 PM
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Sorry if I upset anyone, I'm clearly not very good at being secretive. I edited my post FWIW, I just wanted opinions on what I was buying and still I remain confused, and it is an absolute PITA to fit a new turbo with and without the manifold to see. I knew, and both Stephen and Neal knew what manifold we were all talking about and we all knew what each other knew (goodness this is complicated!), I wanted further comments on it as there is very little on this particular one, and I couldn't find any decent old threads, anything on the net or the vendor's website, and anyone I approached off line all had different opinions, but not many had actually use one. If I stick a VF23/manifold on and it is tepid low down then is that the VF23 or the manifold or both? I wanted experience just to make my car quicker not to slag off any product or drop anyone in it. Sorry for any offence, certainly not intended. The technical comments really are most appreciated honestly 
It sounds like it just didn't work on Neal's car because of a TD04 and a restrictive exhaust. Extra in the 4000-5500 range should be just ideal for a VF23. I know it will be crap below 3000 RPM whatever I do, but now I think I would rather lose between 2000 and 3000 and gain from 4000-6500.
Surely this is the place to discuss experiences with different products. Just because Stephen, Pete and myself have various related or unrelated commercial interests should not prevent this occurring and these are all declared.
If it does not work on my car, it is not because the product is no good, it is because it is not MATCHED to my car. We'll see, but I have a sneaky suspicion it might work better with a VF24 rather than a VF23.
[Edited by john banks - 6/18/2002 1:29:58 PM]
It sounds like it just didn't work on Neal's car because of a TD04 and a restrictive exhaust. Extra in the 4000-5500 range should be just ideal for a VF23. I know it will be crap below 3000 RPM whatever I do, but now I think I would rather lose between 2000 and 3000 and gain from 4000-6500.
Surely this is the place to discuss experiences with different products. Just because Stephen, Pete and myself have various related or unrelated commercial interests should not prevent this occurring and these are all declared.
If it does not work on my car, it is not because the product is no good, it is because it is not MATCHED to my car. We'll see, but I have a sneaky suspicion it might work better with a VF24 rather than a VF23.
[Edited by john banks - 6/18/2002 1:29:58 PM]
18 June 2002, 01:37 PM
#29
Neal, you are not alone in having a MY00 with unusually low power. Mine only produced 201bhp at PS in completely std form. It's a little better now with a different OEM ECU but I'm not lucky enough to have one of the good ones, especially when one particular MY00 car with a TEK 2 and std exhaust, made more than most with many more exotic mods.
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