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Old 18 Aug 2009, 09:36 PM   #1 (permalink)
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Advice please

2 main questions;

1. Under boost, especially in 5th gear, revs jump from 4k to 7k'ish with no gain in performance - not all the time yet, just every now and then. My view is slipping clutch and need replacement pretty soon? Been driving it really gently since just after I got it as noticed something odd after a couple of weeks.
2.Hole in performance - 4k to 5k revs flat spot when above not happening - could this be related to above not being capable of putting down power or just need for re-map?

Damn Prova ECU's - nobody seems to want to touch them! Wayne - help appreciated if possible :-)

To question 2 - I would add that I will (at some point) get the Simtek upgrade but unless Alan wants another car to sponsor it will take a while :-(

(btw Pilot - still no answer from the guys near you but thx for the pointer)

Cheers guys
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Old 18 Aug 2009, 10:24 PM   #2 (permalink)
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Re: Advice please

no worries chap,will pop in and have a word with them n see if i can get a responce out of them
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Old 19 Aug 2009, 02:05 AM   #3 (permalink)
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Re: Advice please

All the info I could find on this ECU (in English) is negative. Take a read;

Quote:
Be careful fitting something like the Prova ECU, and running on UK fuel.
The Prova ones are designed to push the limits of Japanese 100RON fuel or better, with very little allowance for anything lower. Standard ECUs will cope with down to 97RON OK though, despite expecting an average 100RON. So unless you're planning on using that hideously expensive BP 102RON fuel or a lot of octane boost, you seriously risk detonation issues...
Quote:
Unless you could guarantee that the ECU's are mapped for 99 or lower I've leave any aftermarket ECU alone. I've got a Prova Eiffel ECU sitting in the shed gathering dust because without booster the car runs really bad. The only regret I have is I never had it on a RR with the Prova ECU and booster to see how much power it gains. When it was running on the Prova ECU on 99 (before I knew it was fitted) it had less power than a standard ECU on 99 run on the same RR.

Quote:
Originally Posted by COBB Tuning
Thank you for your interest in COBB Tuning products. Yes, the Prova and Cusco AccessPORTs are the same as the COBB Tuning AccessPORT. These products are made for Japanese Domestic Market cars and are sold exclusively through Prova and Cusco in Japan. Any calibrations that are available on these units will be designed for Japanese market cars and fuels.
If your car is standard, it might be worth shopping on e-bay for an original ECU for your car. Would ditch the Prova ECU asap mate if no one is willing to touch it. May even be doing your engine harm.
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Old 19 Aug 2009, 05:29 PM   #4 (permalink)
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Re: Advice please

As for the clutch get it as hot as possible city driving to test it and then go away lift up hand brake put into first gear and try to drive off car should want to move and edge forward but if it dont and if clutch slips you know clutch at fault but as for the symtoms sounds clutch at fault
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Old 19 Aug 2009, 10:48 PM   #5 (permalink)
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Re: Advice please

Quote:
Originally Posted by stiimpreza1984 View Post
As for the clutch get it as hot as possible city driving to test it and then go away lift up hand brake put into first gear and try to drive off car should want to move and edge forward but if it dont and if clutch slips you know clutch at fault but as for the symtoms sounds clutch at fault
I always thought it was a high gear? not 1st, when my clutch was going to showed up in 5th first(as mentioned above in question 1) then as it wore it would do it in 4th then 3rd etc
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Old 20 Aug 2009, 04:33 PM   #6 (permalink)
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Re: Advice please

Thanks for the advice guys - cheers Pilot - for info I have been told that the PROVA is just a modified version of the STi chip but should be flashable. We will see!!!
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Old 21 Aug 2009, 11:28 PM   #7 (permalink)
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Re: Advice please

Quote:
Originally Posted by bugeye_bob View Post
I always thought it was a high gear? not 1st, when my clutch was going to showed up in 5th first(as mentioned above in question 1) then as it wore it would do it in 4th then 3rd etc
Ya true bud but thats another way to test it to
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