Ive got a wierd problem that im sure the pf experts can solve.

Under heavy load, say pulling from lowish rpm in 4th, I can hear/feel the turbo almost fluttering/stuttering. I can also 'see' this on the boost guage, the needle shakes slightly.

Turbo is standard, wastegate is standard and set as it left the factory.

Any ideas?

 

possibly your actuator is failing, Get a -31 and a good set up and you should be right

 

Its not a ford

 

Could be something like the cat collapsed, causing the turbo to surge.

 

sounds like surge i dont know why youd get it on a standard engine though

 

No cat on the car to collapse, so rules that out.

Could a standard turbo on essentially a standard engine actually surge?

 

does seem very strange ? i wonder if a restriction of airflow could cause it from a collapsed or blocked intercooler

 

could removing the cats from a 4x4 with a t34 cause the turbo to surge???

 

my car was surging very badly before i had it mapped very loud fluttering and car stuttering badly boost gauge was jumping up and down about 7 psi

 

ive had 3 cossies on t34s with free flow exhausts all pretty much standard engines and none of them surged although they all had .63 rear housing so boost was late. might be possible on a .48 exhaust housing as there be loads of volume of air in low revs. what exhaust housing you got ?

 

All the intake system on my engine is silicone/hard pipe so no standard rubber to collapse.

Surely a intercooler problem would show it self all the time, not just under heavy load.

I suppose the one answer is to stop being a lazy cunt and drop a gear

 

.63 and it was mapped with the cats and all i did was bash the insides out so their hollow tubes now

 

It could be that, labouring the engine, which is forcing the turbo to produce more boost before the engine has enough speed to consume the air.

Unusual for a standard car IMO, but not entirely inconceivable.

 

as your exhaust is free flowing now gas in theory can escape easier therefore the turbo may make boost a bit earlier and harder therefore causing more boost lower down than it was mapped for hence creating surge maybe

 

is the wastegate sticking

 

Daz - What are your symptoms? You sure you have 'Surge'?

As opposed to a boost spike?

Surge is usually along the lines of the turbo producing a volume of air before the engine is ready to consume it, hence why alot of BB turbo's surge. Removing an exhaust restriction is unlikely to produce surge IMO.