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281BHP Is just not enough!!!

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Old May 7, 2002 | 10:03 AM
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ok jake, just wanted to make sure you had decent brakes, suspension etc before upping the power any more.
that's the way I did it also.
I am also looking at FMIC right now, so would be interested in the replies you get as I have a similar setup to you, just older car

shunty

[Edited by shunty - 7/5/2002 10:04:53 AM]
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Old May 7, 2002 | 01:47 PM
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From: 32 cylinders and many cats
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Shock horror, I agree with you Adam If the pressure drop is not increased across the intercooler and the charge temperatures are lower then surely you will get more torque (on a MAF based system certainly, and on a MAP based system if you add fuel).

[Edited by john banks - 7/5/2002 1:49:00 PM]
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Old Jul 5, 2002 | 08:43 AM
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OK I have managed to squeeze 281Bhp & 265 ft lbs of torque out of my MY00 UK with an HKS Superdragger & PET75 downpipe mapped by Ecutek. But I want more!!!! and not being very technically minded I am not sure which route to go down with a budget of approx £1500? possibly Big turbo or FMIC or Equal Length manifold what are my options.

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Old Jul 5, 2002 | 08:48 AM
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Jake - out of interest what else have you upgraded on your car, anything ??

shunty
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Old Jul 5, 2002 | 08:54 AM
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Ive got an HKS Racing Suction Kit which is a quality bit of kit and apart from the Six Pots and wheels thats about it and I know the figures are high but thats down to Mervyn at PE.
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Old Jul 5, 2002 | 09:36 AM
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Can you increase the boost any more with the mapping?.
Sorry, but you dont way how much you run.

A better intercooler (front or sti/P1) may help cool the charge if you are having det problems at the current boost limit. assuming that is the limiting factor.
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Old Jul 5, 2002 | 09:38 AM
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I think its about 17psi and I thought the P1s STis and MY00s all have the same intercoolers
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Old Jul 5, 2002 | 10:27 AM
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Jake,

hybrid turbo, fmic then water injection.

you dont want to push the TD04 much further as it will start to struggle and intake temps will rocket.

I would recommend going the hybrid route,

bearing in mind your options, you can consider the hybrid TD04, or something like a vf23/hybrid vf23. Wouldn't bother with a VF22 as it will be very laggy by comparison.

I would consider a turbo dynamics BT270. Give Mark Aigin a call as he knows most about these things, and can supply the above mentioned turbo.

Mail me offline if you want his number.

(ps. would also do a fuel pump before anything else!!!
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Old Jul 5, 2002 | 10:39 AM
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From: wakefield
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Adam M - talking about FMIC's, what gains can you expect on a car fitted with one ? or will it also depend on other mods etc?
Speaking to someone on the phone yesterday, they told me very little in the way of power & torque, but the suppliers of pace, blitz etc say 20bhp gains & sililar torque....
what are you personal opinons.

cheers

shunty
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Old Jul 5, 2002 | 11:53 AM
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Adam,

Thanks for the good advice mate I will look into a new turbo first. Whats the performance difference between a normal VF23 and a Hybrid VF23? what I am trying say is would it be worth fitting a bog standard VF23 to save money or would you advise to only go the hybrid route?


Jake
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Old Jul 5, 2002 | 12:20 PM
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From: 32 cylinders and many cats
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Depends on what you want to spend?
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Old Jul 5, 2002 | 12:51 PM
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A Grand
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Old Jul 5, 2002 | 01:07 PM
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Sorry to Hi-Jack your thread Jake....

Could JB and/or Adam help me understand what the limits of the TD04 are and why? By this I mean why do the inlet temps rise to dangerous levels when you crank the boost up with a TD04? And what is the max boost limit for the TD04 with say a full de-cat and d/p?

I am interested in going the Hybrid TD04 route and would like to understand a little more...Is it all just down to the amount a Turbo can flow? does it have a 'sweet spot' for flow Vs temp? Lots of questions, sorry!

Thanks in advance.

Neal
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Old Jul 5, 2002 | 01:08 PM
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jake,

either give me a call or email me and I should be able to point you in the right direction.

left my mobile in car come to think of it, but will have it after 5.

07971 228181

Hybrid wise it isnt that simple. you can start where you like with any turbo and choose whether you want mroe power or less lag. In some cases using trickery you can get both with more modern compressor blade designs.

as I said before mark aigin (R19KET) is the man to ask.

have heard johfelstead (who I normally believe) saying fmics dont give you any gains alone but I dont see how this is possible.

if the charge temp is lower than before, then the air is denser so you will need to add fuel. he believes that they only allow you torun at high power for longer, which they will do, but I believe this is in addition to the extra power they provide as they are pretty much always producing cooler charge.

denser air means higher mass airflow which means more fuel for the same air/fuel ratio. Therefore it must be producing more power unless you have managed to drastically change the volumetri efficiency at the same time.

In essence they will give you more power.

John, please prove me wrong if you can!

the trouble is most people test these gains on a rolling road and there is no question that these drastically favour fmics over tmics as the fans point directly into them. They may show you distorted gains, but it is more likely that the previous figure with the top mount was too low rather than the latter figure with the fmic being too high.

For a grand, if you look in the right place you should get yourself a hybrid vf series.

I have recommended the bt270 or equivalent in the past as it seems to work incredibly on a 2000turbo.

tim whiteside made 342bhp @1.25bar using one (also with a fmic and full exhaust including headers) yet still managed to make a bar of boost by 3000rpm. That was pretty good going

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Old Jul 5, 2002 | 01:29 PM
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From: wakefield
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thanks for that adam, very informative.
by the way, I have mailed christianR to have a chat about the intercooler & rad as pace have upped their price on FMIC by £200

cheers

shunty
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Old Jul 7, 2002 | 08:31 AM
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"tim whiteside made 342bhp @1.25bar using one (also with a fmic and full exhaust including headers) yet still managed to make a bar of boost by 3000rpm. That was pretty good going"

....and Trout made 346bhp @ 1.3bar using a top mount (as Adam says - under-reading of course as it is a top mount) and got a bar of boost at 3000rpm

Personally I think the FMIC which I have now put on my car does make it feel 'harder' and power seems to be a little more consistent - but it was not a huge difference - although I did need to add a shade more fuel which implies that it was a useful upgrade - for show if nothing else!

So for your upgrade....

...hybrid followed by FMIC - each will require a remap of course!

Trout
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Old Jul 7, 2002 | 12:11 PM
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Hope we're not comparing Sti's to non Sti's here ? That extra breathing/rev limit that allows Sti's a further 1500 RPM is worth an extra 22% in air flow capacity.
So mods that produce 300 bhp on a UK , if the airflow is maintained pro rata on a STi would produce 366 bhp.
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Old Jul 7, 2002 | 08:04 PM
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Cosie,

agreed.....but - empiracal evidence suggests that both STis and UK that have been modified tend to get there peak power at around the same point - between 6,800 and 7,000 rpm. Of course I would love to get the extra 22% - however my peak power comes around 6,900 rpm - only a few revs higher than the other Scoob referred to here.

Trout
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Old Jul 7, 2002 | 10:12 PM
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I thought it was'nt just about the extra air a fmic would let you flow but that the decreased inlet temps would let you significantly advance the timing.Have I misunderstood something?
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Old Jul 8, 2002 | 12:00 AM
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Andy,

"Hope we're not comparing Sti's to non Sti's here ? That extra breathing/rev limit that allows Sti's a further 1500 RPM is worth an extra 22% in air flow capacity.
So mods that produce 300 bhp on a UK , if the airflow is maintained pro rata on a STi would produce 366 bhp."

First off the rpm cut on a UK is 7250, and the STi 8250rpm = 1000rpm.....

But your above statement assumes all things are equal, and they are not. If it were, it would also imply that if a UK car was getting 340bhp at 7000rpm running 1.25bar, an STi would be getting circa 400bhp at 8000rpm !!!

For a start, as you go up the rpm's, an engines VE starts to reduce. Next, a turbo that may be 80% efficient at 7000rpm, may drop to 65% efficiency at 8000rpm.

I know we're talking about different RR's, but if Tim managed 344bhp running 1.25bar at circa 7000rpm, one would think that your car would have seen much more than 349bhp (iirc) running 1.7bar,

but if you work out the air flow of an engine running 1.7bar at 5500rpm, against that of an engine running 1.25bar at 7000rpm, then take into account the difference in VE, at those rpm's, the outcome is very similar !.

Life should be so easy

Deep,

You're right, you'll also benefit from being able to advance the ignition with a FMIC.

Mark.



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Old Jul 8, 2002 | 12:57 AM
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Mark/Trout

I made the comment as I thought it was possibly inappropriate to compare intercooler performance on a UK vs Sti if the boost pressure was lower on the Sti due to its improved breathing capabilities.

As you are well aware, The Sti has a volumetric efficiency which peaks at a higher rpm than a UK.

FWIW my RA is basically the same as an early UK engine. My peak of 349 was at only 5600 rpm and (a rapidly diminishing) 1.4 bar boost.
Since the latest turbo mods peak power is now produced at 6200 rpm and there is no fall off in boost

Andy
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Old Jul 8, 2002 | 01:28 AM
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Andy,

So you know STi owners who run "less" boost than UK owners, because "their engine breaths better"...... Yeah, right

To be honest, I don't know exactly what the "official" VE v RPM, of our cars is, but generally speaking, it reduces as the rpm's increase. The STI's may have better VE than the UK, rpm, for rpm, but by how much, I have no idea.

Mark.
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Old Jul 8, 2002 | 02:02 AM
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""So you know STi owners who run "less" boost than UK owners, because "their engine breaths better"...... Yeah, right ""

What I mean is that if an Sti is producing the same power as a UK then, generally, it will do it at lower boost due to the increased RPM used.

As a quick 'mini survey' the average max hp rpm of a modified UK is 6280 and a modified Sti is 6900. ( this was just taking an average of the top 10 uk/Sti dyno results from the top of the page )

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Old Jul 8, 2002 | 09:30 AM
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Andy,

I think if you were to compare modified UK, to STi's, with like for like mod's, 99% of the STi's will be running higher boost.

If you want to compare UK ~STi, then you'd need to compare cars running identical mod's, running the same boost, ideally mapped by the same person, and compare the figures at specific rpm points.

I think you'll be surprised at how they compare.

Mark.
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Old Jul 8, 2002 | 12:06 PM
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I know the lighter pistons and increased rev limit will make next to no difference to power output but what about the cams ?
I personally don't know, having never driven a v5 Sti but all the power curves I have seen appear to lack torque around 3 - 3500 rpm then go on to produce power well after 7000. I assumed this was assisted by cam profiles ? Maybe not, could be solely the bigger turbo ? or the mapping ?
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Old Jul 8, 2002 | 06:07 PM
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Andy,

your analysis of the dyno page is a fair challenge - but I wasn't aware that this included the big power UK cars (ie well over 300bhp). IIRC these cars were producing peak power at around 6500-6800. Many of the remapped STis produce peak power at around 6,900 - for some reason I do not understand, an STi V with a JECS ECU will produce it's peak power at much higher revs - however I suspect with much higher boost pressures then the optimum power point - combination of cams, advance, VE, turbo degrades - therefore we push the boost to 'force' the power - but at a cost of optimum efficiency - therefore at lower revs.

Also, Stis with a JECS produce little boost below 4,000rpm, however, again the heavily modded cars will produce good boost from 3,000 rpm (I get 1 bar for example).

Compared like for like cars are much more susceptible to major mods - i.e. Tango got even more power than me () with a UK - but that was with a huge turbo and there was nothing low down and the car was pushed very hard in terms of it revs to get it's final figure of over 350bhp.

As I said - I wish you were right - I would then be well on the way to 400bhp

Trout

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