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Possible power output - Any ideas?


dandan

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Hi Guys,

 

I have a question for anyone who is interested:

 

Can anyone tell me what they think the power output from the following spec would be:

 

Jap spec 6 speed manual

Std J spec turbos

Top small cat still in place

Lower cat removed

Trial s.steel exhaust (approx 3-3.5"bore up to silencer)

Apexi dump valve

Running 1.0bar

 

Can anyone give their opinion on the difference in running this spec with optimax or s.u.l compared to normal u.l I'm guessing the ECU will be retarding the ign a fair bit if running on normal.

 

I know this is heading for a BPU sort of question but not found any figures relating to a similar spec. Some people have told me the J spec cars put out well over the rated 280bhp and are up with the uk cars power wise. Do the J specs produce slightly greater torque than the uk cars too? I just wondered what this sort of spec would achieve.

 

Thanks for any opinions guys.

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Originally posted by dandan

thanks terry.

 

I see, i thought perhaps up to 340-350 ish?

 

Has anyone had similar mods and been on a rolling road and got some figures?

 

325hp I would suggest.

 

As Terry says you are only boosting a few psi more than stock with basic mods.

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sounds good mike, pretty quick then i'd imagine!

 

i'm hoping for 330-340 at 1.0 bar. don't really wanna push the turbos too much just yet.

 

are the j specs really down by 40bhp to the uk's? has anyone got any meaningful figures from same rollers to compare at all. i know this has probably been discussed before but i find it hard to believe there's such as deficit.

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Guest Terry S
Originally posted by dandan

are the j specs really down by 40bhp to the uk's? has anyone got any meaningful figures from same rollers to compare at all. i know this has probably been discussed before but i find it hard to believe there's such as deficit.

 

No there is very little in it. Both around the 320 ish stock.

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I actually believe the J-Spec's to be around 300bhp as standard IMO, but the faster spooling turbo's give more low down torque than the UK spec and so 0-60 and even 1/4 mile there isn't anything between them. Top end the UK specs should begin to walk away slightly.

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Interesting....

 

Can someone give an opinion on (roughly) what mine would be putting out, with the following:

 

Standard J-spec turbos

Super AFC

AVC-R

Hiper, catless

"motorsport" fuel pump

FSE valve

HKS Super Power Flow induction

HKS S-Type FMIC

Denso IK24's

1.25 bar

 

 

Cheers!

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Regarding mods, am i right in thinking that intake mods other than a dedicated cold air feed don't really gain anything over a decent panel element until higher tuning levels than the stock turbos.

 

What else on the "lower budget bpu" side of things can be done before intercooler or hybrids?

 

Is it a case of upping the boost to perhaps 1.2bar as long as the fuelling stays ok?

 

n.b. already have decent exh, lost 2nd cat, dump valve, fcd, ebc and t.timer.

 

opinions people?

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"Induction kits" (cone filters) do bugger all with the stock turbos really. I would strongly suggest getting a dcent IC before getting too boost happy in view of the recent melted engines we've seen on the board. It is becoming apparent that the MkIV is a bit vulnerable under heavy sustained load, even at boost levels which were previously considered "safe" on stock fuel and stock IC. For my money, I'd get a boost and peak hold/warning EGT gauge and check your IC condition out before going above 1bar.

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cheers adam,

 

the car has an hks peak hold boost gauge but no egt as yet. no doubt that won't be too far away.

 

if the intercooler looks ok (not too many bent fins or too much cr@p in there) i may leave it in place and go down the water injection route for now. much much cheaper than a decent fmic even the fully mappable aquamist system

 

so do people think 330bhp is around the reliable limit on a j spec without improved charge cooling and fuel mods?

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One approach would b to install a temp sensor just before the thorttle body and see just how high your charge temps are getting at certain boost levels. It's best to know these things rather than guess at them. There was a thread on it recently.

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yes that is something i am definately planning to do. probably go for the maplins wide range temp module until i find a more elegant and permanent solution. interesting to measure temp changes from turbos to plenum. nice to do the same with pressure too, see how much is lost through the core and the pipework.

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