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Hey all... has anyone got any comments?

600 x 300 x 80 Fmic

3 Inch exhaust dump back.. standard cat

Stainless exhaust manifold

Gt 30 with vg30 rear

Walbro pump

Sard fuel reg

Standard computer

Standard injectors

Iridium plugs

any thoughts?

post-24852-1137459394.jpg

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they leave it in second cause it will go to redline without trying to change into third early.. but the gearing of second is prob only a little lower then a manual third

What gear is typically used for an auto on the dyno?

the lean spot at the top is the rev limiter..

Based on what I have seen, rev limiter = rich, not lean.

Regardles it can't be on the rev limiter from 90 kph to 110 kph.

My guess is the injectors are maxing out. Based on your PM, the fuel pressure at 50 psi plus boost is quite high, maybe the Walbro fuel pump can't handle the pressure and its flow is dropping off. That needs to be checked next time on the dyno.

:rofl: cheers :)

Edited by Sydneykid

I didnt get a print out from the dyno showing when the boost was coming on etc, but i know it was only running at 13 pound to make 228kw, and from driving it i would say just over 4

The dyno graph looks like a fairly straight line so it obviously isnt surging or laging to badly.. i think 40kph on the graph is around the 3000 rpm mark.. i dont know if that helps... i could prob go back to the dyno and get the other print out if it will help..

can you tell me what the lag is like? I have a GT30 with a VG30 rear too..

Full boost in second at 4900rpm..........

GT30 with VG30 housing (700177-5011) TO4S 7 blade wheel

Nismo 550cc Injectors

Walbro 220lph Fuel Pump

FMIC (600x300x75)

Full 4 inch intake

powerfc and Datalogit

Q45 afm (90mm)

Full exhaust thats huge, hi flow cat

95ron fuel

220rwkw, and 470nm of torque at 15psi

Full boost in second about 4800 - 5000

Full boost in third about 4500

Full Boost in 4th is about 4200

Fitting a RB25 Standard exhaust housing to it on the weekend. I think the VG30 may have been ground out too much.

Edited by The Mafia
it can't be,  the lean spot is the tuner backing off the throttle, hence going to a lighter load point, also why the power drops off..

It's lean before it gets to that point.

I had the Walbro. Doesn't seem to flow very well up high. Ditched it.

Same problem i had with my walbro :w00t:

he why its being used as a lifter pump rather than a main pump.

Very crappy things the walbro's.

I was from 12afr's into the 10's with just a fuel pump change and nothing else.

so what are you running now?

and if its a external pump where did you mount it.. cheers

Same problem i had with my walbro  :)

he why its being used as a lifter pump rather than a main pump.

Very crappy things the walbro's.

I was from 12afr's into the 10's with just a fuel pump change and nothing else.

i just went and picked up my other dyno sheet showing the boost...

Damm gizzmo ebc... cheap and nasty... set on 13psi

but it dosent hit 13pound till 6000rpm then dies again.. grrrr...

anyone have any suggestions on smothing out the boost line?

makes good power at 7000rpm at only 12 pound.. hmmm B)

post-24852-1137566532.jpg

they do it in the gear which is closest to a 1:1 ratio. so im told.

they did mine in 3rd(left Overdrive off)

IMO that PSI reading is weird

mine goes straight up to what its set using a $22 controller.

doesnt fade off untill 5,500-6000rpms

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