As title.
Its a vf35, and when mapped didnt make great power, but it still worked alright, and torque was ok. 261BHP and 275 torque. Not great but works. But is now running out of puff, it was at about 5500 but now has gone down to 5000, is this turbo dying on me.???

I have checked for leaks etc and everything seems fine.

 

sounds like it is, although do you know if its holding boost?

 

could be a blocked cat if still fitted or exhaust is blocked

 

its fully decatted.

And yes its holding boost from 3200 to 5000, but then it just doesnt go anymore.

It also when putting foot down its doesnt boost, then if you lift off and then put foot down it does,

 

On all my turbos I have noticed power drop off after 5000rpm, I have went thru quite a few and when people say they pull to the redline they don't, have you not considered its the way the turbo is now mapped? Even now on my gt35r I still notice it not pulling as well after 5000rpm. This is all based on say 3rd gear and above.

 

Has it been mapped for that turbo? looks like it hasnt if its only producing 261bhp or you have some severe issues

Tony

 

I think tony has a point,my MY99 with td04 and no remap produces 241 bhp,and the vf35 suppose to be good for 350 bhp - your nearly 100 bhp down on what it can produce,so has it been mapped correctly ? ? ? ?

 

Def something up there.

 

silicone inlet pipe sucking shut?

Simon

 

Yeah been mapped by Pat. So I guess it been mapped properly, or to what the turbo can do in its state. Couldn't get anymore then 1.2 bar peak. Nightmare
silicone tube could be sucking in, but how can i tell?

God I need someone to look at this and see whats what.

Must be a proper issue somewhere

 

easiest way is to put it on the dyno and watch the pipe.. if it was doing it when pat mapped it he would have noticed.. but could have started since.

Or you can stop it being able to suck shut and then you know it's not.

Simon

 

If it wasn't doing it on the dyno and only got 261bhp then there is still a problem...

If you have an induction kit on it - try swapping back to the std airbox - it might be the filter on the end is too restrictive and causing the collapse.

 

how can i stop it sucking shut?

 

I have panel filter in standard box

 

it could have been restricting though and not fully shutting..

 

Althought turbo sounds an issue also..

haven't you posted before about low figures? same turbo or did you change it?

Now using CJ's engine iirc?

Simon

 

Dynamix where you based and could you possibly have a look?

 

I am now on CJ's engine, same turbo. Still low figures.

 

sounds like the issue then, any noise from turbo?

 

Cambridgeshire - happy to help - where are you ?

 

Well funny you should say about noise from turbo as on bigger loading like 4th and 5th, you can hear it, it sounds like a sucking noise.

I live in shoreham, bit of a trek, but might be worth it.

Other then mapping, can you check it over and see what is going on?

 

Might be easier/quicker to get it up to surrey rolling road when Simon is up there - I am not down in west sussex for a couple of weeks.

 

Yeah could be worth it. Cheers dynamix

Simon, would you be interested in helping me out?

 

Just wanna square this away:-

If you have a large enough air filter (or filter/MAF combo) that's capable of more than enough airflow through it, for the particular turbo/boost level/engine capacity it's fitted to - i.e. the volume of air pumped through it on max boost for one complete engine cycle - then the turbo intake pipe should NOT collapse... Even if it's a cheapo, easily squashable one?

Is the above correct (based on elementary physics)?

Cheers.

 

no it still can squash

 

Sure.

But for what reason/s?

 

the pipe itself is a restriction, or rather has suction within it and will collapse is crap enough with no filter.. compare a paper straw to a plastic one..

Simon

 

Ah, your straw analogy works for me. I get it!

Si, aside from the pukka Samco (mega bucks @ c.£200) reinforced intake, and the Viper Performance one, do you know of any other silicones that defo won't collapse? (The Viper v.3/4 one is cheapest at £169, so would be looking for a cheaper v.3/4 one than that...)

 

analogy is always easier to follow I find.

no is the easy answer.. you could make an ally one with silicone on the ends..

Simon

 

Agreed - people can much more easily relate to tangible comparisons that they're likely to experience in life, more than a physics lesson.


Need the breathers, so think I'll just take the hit on the plastic and get the Samco and be done with it....

Thanks.