Stumble at high revs

Hi guys, need an assist on this. The car stumbles at hi revs but I don't get it that often. Not getting white smoke from the exhaust so the turbo seems fine. Changed spark plugs today and tightened pipes, but it still happen. It doesnt seem to occur when i'm in 4th (for example) and accelarating right through the gear. Occured when I dropped from 4 to 3 tho. My Walbro fuel pump should arrive soon so i'll change that out. Has anyone experienced something like this before? Is there anything else I can look at.

ok, jusst went for short drive, found that if you accelarate gradually thru any gear, its fine. But once u race thru 1st then get to 2nd at about 5000rpm, it stumbles. Same story with third and fourth, seems as though something or the other can't keep up.

Fuel pump i think, fit it and see what happens

myn does the same as soon as i get 5000 and 0.8bar boost

Your fuel pump installed yet poizen?

no hasnt left the states yet 🙁

I bought the same as you did, cost me $99, still waiting 🙄

same cost $99 = free shiping jus waiting i keep emailing da oke but no reply

race through gears, high revs...

rev limiter???

veecee wrote:

race through gears, high revs...

rev limiter???

nope vc not that it like you got fuel line full of fuel then a air pocket so it skips just till there furl again and then takes off am i right reecez

Yup, exactly whats happening, if i drop the hammer in 1st car will rev happy to 7000, after shifting and its still in high revs thats when it stumbles, just hope its the fuel pump. gona park it off until i get the FP, don't wana do any internal damage.

Mine did that for a while and then it just sorted itself out.

Pull strong now without doing that.

Mine only did it on cold mornings and at night when it was cold.

I suspect It has to do with the AF ratio, since I was boosting higher and thus my AFM gave a wrong reading or so and to much air and not enough fuel.

But ja its sorted now!

its weird it will do it sometimes, but i getting tired of the whiplash from the stumble 😛

I had a similar thing but it only happened when I was relatievely low on fuel. It only happens when you change to 2nd or 3rd in high revs. The walbro seemed to sort it out.

@ Trance after ur conversions done I think ur gona need dual pumps 😂

At what rpm does the voltage to the feul pump change, 5000? Ek dink jou pomp is in sy p**s.

why do u say that?

Im to lazy to read so im thum sucking here but i think that somewhere in you revband the ecu send higher voltage to your fuelpump and also change the vacuum via the acc valve to your fpr in order to juice a bit more but if the voltage change doesnt make the pump deliver more fuel pressure you might have this affect due to starvation. Maybe VC or someone knowing the car better can correct me on this.

when it cums 2 electronica im totaly lost

hey reecez i got my walbro today so you should be geting yours soon