Can anyone solve this boost problem??

[Chris Lynch]

Hi lads and lasses,

Ive got this problem with my car I must sort out. Ive posted this on other MR2 forums and no one has been able to solve the problem?? short of taking the whole thing apart is there anything else this can be?

Car is: Rev 3 t-bar turbo:
Blitz ID3 EBC
HKS Filter
HKS BOV
Apexi N1 exhaust
TB development downpipe

I fitted the boost controller and down pipe myself the other things were on the car from Japan, it also had a turbo timer and boost guage which were removed at SVA time.

I have fitted the boost controller correctly and it works because if I switch it off I only get 7PSI.

When its on ive set boost to 18psi. Boost comes in as normal and climes to 15-16 psi but as the revs increase it feels like the wastegate is opening and the car drops back down to about 13.8 PSI. It never gets anywhere near 18. In fact ive set it as high as 20 and it does the same regardless.

Ive checked all the piping 20 times and its correct. The only thing I can think of is the wastegate is not up to the job. I assume this means a new turbo? is there anyway of testing this? as I don't want to fork out for a new turbo and have the same problem?

Someone has suggested it could be the actuator but I am sceptical about this? does anyone think it could be the problem??

Ive got a few other parts to fit and want to get started with more mods but obviously I need to get this sorted first.

Sorry bit of a long one for my first post, any help would be really great.

Thanks

Chris

[PW@Woodsport]

if you plug the hose coming from the turbo so that nothing is getting to the actuator you should be able to boost until fuel cut (rev3 17psi??? someone correct me if thats wrong)...if you can hit fuel cut then the actuator musnt be up to the job...but you could fit a grainger instead to cure that...ie the actuator wont see any boost pressure until the grainger says so,then it will get the full pressure at your limit.Either way blocking off the turbo to actuator pipe will give you a better idea of whats going on.

[Chris Lynch]

Thanks paul, I had not thought of trying that.

I thought the EBC would drain off the pressure to the actuator? are graingers more efficient?

Chris

[sanke]

Hi Chris this may help
I had a HKS BOV (not the new type SSQV)and it did the same sort of thing yours is doing, It could only hold between12 and 13 psi. Changed to uprated turbo still had the same problem. Went to a rolling road in "Dudley", there only comment was its over fueling So Looked hard and found with the new turbo I could see the bov lifting off its seating when throttling up the engine. So replaced with a new bailey recirc BOV which claims to hold 60 psi. Went out for a run 1.8 bar @4000rpm so had to readjust the AVCR back down. Also the induction noise changed, much quieter. and a lot moooooorrrrre go.
Moral of the story try a different BOV
And as for the place in Dudley SHAME!! Perhaps they should let the customer set what there up to whilt thrashing their car!!

[Chris Lynch]

Do you know what you might just be right as someone from the US IMOC was saying something to me about BOV's when I was in Vegas with them last year but I was a bit drunk and did not really know what he was talking about. Will try a different one. Where did you get yours from??

Will try and take a pic of my HKS BOV to see if its the same one you had.

Chris

[sanke]

Hi Chris
Direct from bailey, arrived two days later good service.