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INASNT

We could have them turned around in 2 working days.

T0nyGTSt

If they were top fed Bosch type injectors then you’d be right. But getting new side feed injectors for around $150 is a tough ask.

Judd

The injectors are drilled out and tested under pressure with a solution similar to petrol. What were the negative results you heard and why do think the spray pattern would be affected? If they were GTR injectors with their different seating arrangement then you might have a valid point.

MRK25T

The graph with the A/F ratio shows 12:1 a/f ratio under 3000rpm (full load I presume). Seems a bit rich for the rpm range and power the engine is putting out at that point. The rest of it looks fine and the engine should be healthy for a long time.

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I think the problem with drilling out injectors is getting it done properly.

Like any sort of work, quality is everything.

With new injectors you're guaranteed that, no?

It was my impression that new side feed RB25DET injectors were available for well under $200.

T.

Mark, I not 100% sure which way you took my last post. I was suggesting to have your injsectors cleaned (off car by a pro), not to replace them. If you did take it the way I meant then just ignore me... Hopefully you get it sorted!

Originally posted by MRK25T

So I need to upgrade my AFM to a z32?

Mark

Are you happy with the performance of the car, or do you intend upgrading further. I did use a Z32 when I had this problem, when it was redynoed, I got a better rwkw figure BUT it was done in different states by different tuners so it is hard to compare. They did a before and after dyno, however as soon as you put on a Z32 AFM and select it on the power fc, the mixtures go rich. My injectors went from 78% to 89%, after a retune it was down to 83%. My air flow now only goes to 4.4v, so I have a bit of room left for the turbo going on in a couple of weeks.

I have heard arguments for and against. They cant really hurt except the hip pocket as you have to buy one and then get the car retuned. If you are wanting more power, and intend doing further upgrades, I think they are a good idea.

Alternately, the Z32 upgrade idea has been discussed in a bit of depth on this forum, perhaps do a search.

If you do want a Z32, there are some for sale at the moment for $300 with plug. They are a pretty easy swap.

Majanal,

I've got no idea why I said that to you before... it really doesnt make sense. Someone must have slipped something into the coffee at work =)

Steve,

I like the car as it is - it absolutely flys! I dont like the engine check light coming on because I worry about doing damage to the car. I wont be upgrading any further because the next step will cost far too much.

When I get into my car again i'll have a play with the commander and see if i can switch the AFM check thing off. I'll let you know how it goes tommorow.

Ustasa,

I was with the tuner when he did my car. I made sure he tuned it for reliability rather than for power. Being a beginer to cars, what i think he did was tune it just before it started pinging, then he reduced the timing by 2 and did filled in all the dips etc. with the power curve, then he reduced the timing by 2 again as a safty buffer. After it was tuned he set some stuff so the engine would shut down or something if the engine reached somewhat impossible/improbable levels - just in case.

I've just been to my mechanic that did all the work (except for the tune) and he took me for a drive - since I cant drive.

I now know how quick the car is, I just have to start modifying myself to be a better driver.

Mark

T0nyGTSt

You are spot on when you say quality is everything. The main reason I’d go for high flowed injectors is that when the flow bench says one injector is 595cc and another is 596cc I know personally what each injector is flowed to. If you buy new injectors you can only be 99% sure of the flow unless they come with a factory sheet with the specs for the individual injectors.

$170 for new 550cc side feed injectors is an excellent price and they are a good choice for stable idle and potential power of a internally stock engine.

MRK25T

That sounds like the type of tune I’d employ so stick with the guy :D

There was too much trafic on the road this morning to test out Steves suggestion. Hopefully when I leave for work there wont be as many cars on the road.

Steve,

I think i found that option in the second menu where you select the optional boost controler. I'll keep you informed how it goes tonight. Fingers crossed that it will solve my problem so I dont have to fork out any more money.

Thanks for everyones help.

MArk

  • 2 weeks later...

Hi,

does any1 know how to read the AFM voltage and the battery voltage is over 5 or not..... cna v check form the PFC?????

Cos I have the same problem as well.....

And also when I check the PFC, the knock sensor goes about 100 , is this acceptable or not.... I mean if this mean the car will blow up sumthing........later..........

Cheers

Hi,

I think AFM in the PFC not present as voltage...... I just check again first thing 2moro .......

Steven: when even I hit the engine check light I will back off...... but sumtimes it still hit 100....... may be I need to be quicker..... : )

Killer-T : How much u change ur forged pistons...?????? 5k+????

Guest INASNT
Originally posted by KILLER-T

No the pistons were around 2500 and i think steve is giving you good advise get your car on a dyno just to be on the safe side you dont want to end up like i did with a few cracked ringlands and fork out for a rebuild

when u pulled the engine apart to put the forgies in did u put in short penned rods, get the head ported abit, check the crank for micro cracks etc???

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