crazy tuning issues

[RacerXJ220]

3rd gear pulls I can tune to about 11.5.

4th and 5th, at the same SAFC changes are lean, 12.5-15.

What causes this? fuel pressure regulator?

I have to lean it out to about -15 across the board to get the 11.5.




ANOTHER ISSUE.......

if I go WOT at 4K+RPMS I run lean, and stay there, around 13.5+ at 10PSI in ANY gear. It's like I have to load the FPR. WTF???

Any feedback appreciated. Thanks.

Jeff

 

[IJ.]

Running out of fuel flow on the top end?

 

[jdub]

Running out of fuel flow on the top end?

That's what it sounds like

Are you running an adjustable FPR? That will help the Walbro get the gas to your 550's.

 

[IJ.]

I'd chuck a gauge on the FPR and watch what it's doing under boost.

 

[RacerXJ220]

I am waiting on my Defi electronic fuel pressure guage to arrive... That's all I really need to monitor the fuel.

But its so significantly different from 3rd to 5th gear. Makes me wonder if I just need to swap to another FPR. This one is adjustable, and the walbro is wired straight to the battery. Fuel filter has less than 2K miles.

Today I will fine tune the MAFT settings and see if I can't get around this issue. I put so much into this car already, I'm about to give up if I can't get it running right.

 

[dbsupra90]

do you have a good vac source on the fpr?

 

[jdub]

Aeromotive AFPR

You get what you pay for

 

[cnewingham]

good luck with the maft (assuming you are using the original). Mine was the same way so I did a base setting with it and fine tuned with the safcII however after numerous datalogs, $$$ at the dyno, it was never consistant. Ditch the maft as you are better off with the lex/550 combo or maybe maft pro(never used it)

 

[MDCmotorsports]

Where are you hi/lo throttle settings at?

Need to change them to 69% low 70% high. I bet ya the problemo goes away.

 

[RacerXJ220]

good luck with the maft (assuming you are using the original). Mine was the same way so I did a base setting with it and fine tuned with the safcII however after numerous datalogs, $$$ at the dyno, it was never consistant. Ditch the maft as you are better off with the lex/550 combo or maybe maft pro(never used it)

Yep, I'm using the original version, it's actually Jonez' BETA version that he tested.

I bought it a LONG time ago while I was overseas.

I don't really have any other options unless I purchase more electronics for my AFM because they went bad... And even though I have AUX set to "C" I still have fuel cut at 14PSI. I bet I'm making close to 350RWHP though, and my turbo is best at around 20PSI, so I'm not close to feeling good.

Thanks for the feedback guys, I really appreciate it. I may try the MAFT Pro later on..... but if it's the same I'd rather get a VPC.

 

[RacerXJ220]

Where are you hi/lo throttle settings at?

Need to change them to 69% low 70% high. I bet ya the problemo goes away.

I'll give this a shot.


The problem though, was still present until last night. I usually sink deep into the 10's on my A/F when boost hits in any gear. Last night, for some reason, I think the MAFT started working correctly without me changing it. Now at AUX C it's almost like it's tuning correctly.

My engine seems to be getting better now, after five tanks of gas.....

 

[RacerXJ220]

Went to the track today, boosted about 20PSI, and then I get blowby? But the AEM wideband says I'm deep in tht 10's for a/f?

Blowby caused by too much gas??

I still get 20PSI vac, and there is not smoke at idle.

Too much oil in the pan? (7qts, aprox.)

I'm stumped.

 

[chriso]

I have the same problem. I tuned my AFPR to 36psi with the diag jumper in place but running pressure is 32psi. When I hit boost I am running way too rich at <10 on my MAFT and AEM WB. Should I jack up my fp. I am running 550's and a MAFT Pro in speed density mode.

 

[dbsupra90]

Went to the track today, boosted about 20PSI, and then I get blowby? But the AEM wideband says I'm deep in tht 10's for a/f?

Blowby caused by too much gas??

I still get 20PSI vac, and there is not smoke at idle.

Too much oil in the pan? (7qts, aprox.)

I'm stumped.

why do you have 7qts of oil?

 

[NeoJester]

I deffintly thought that the 7m got pissed past 5quarts