Fueling Questions

[freyb]

thanks for the tip!

[Rolls]

Car is much angrier with the fuel pump in. I wound in some more boost ...., wound in some more timing ... and took fuel OUT of the transition point as it was too rich, seems to hold 12.5 all the way through(might just be the cold air).

What do you think is going to happen when it is 28c outside and you've been idling at a red light for 2 minutes after giving it a flogging (massive heat soak) ? My guess is it is going to detonate.

Either set up a coolant temp/intake temp ignition trim fuel richen map, or retune it on a hot day if you want the motor to last.

[No Crust Racing]

An update to this.

Fixed boost controller leak, now running 17psi and in 3rd and 4th I have that by 4k rpm, a few more revs needed in second (I have a plumb back bov though so once it's on it stays on well between changes - this is a track car).

Installed RX7 460cc injectors (These are from an 88-89 FC Non turbo and ease of fitmet depends on what seals were provided, but otherwise go straight in. Cheaper than GT-R units by a good margin and were cleaned and had new seals/pintles and are 20% larger than stockers instead of only 16% like the GT-R units. Guy on ebay seals them from the US.

Installed Z32 AFM.

Bought a remap from the UK (for GT-R injectors, Z32 and GT2560 on 17psi) as CA tuning is much bigger over there and prices are hell cheap. Found my ECU had already been socketed so chip swap was 2 second job. Slightly larger injectors also gives me more head room and results in a richer tune which I like. (Base timing adjustment required also - timing light used).

Wideband shows AFR's on full boost at WOT do not go above 12, coming onto boost it's in the low to mid 11s just at transition.

Car feels largely the same up to about 100km/h but pulls harder and for longer than it did from 100-160+ now, it's happy enough holding that boost til 7krpm too and I'm not game to rev a stocker any further and will likely only do that on hot laps.

At least now if I clutch kick it in second at 70-80km/h it'll spin and keep spinning.

Off to Winton on Monday to see if the lap time can be improved at all.

[Rolls]

Why would you buy a remap for a different car? Could get a nistune fitted, tuned and installed for only ~$700

Would transform the car, surely it is a bit doughy down low with it running ~10% richer?

[No Crust Racing]

Should have clarified. Remap from a tuner for those mods. In the UK they do it need for speed style stage 1 = these mods, stage 2 = some other mods, stage 3 = the mods I have (with the exception of my slightly larger injectors). The UK has a much larger CA user base and as the CA ECU is so easy to socket and swap EPROMS in there are Remap chips available very cheaply everywhere.

You're right, I can get a Nistune for that money, which I simply can't justify on a hobby. Dr Drifts Remaps are $350 also.

This one, from a tuner who is tried and proven on a number of CA forums in the UK, was $35 delivered. If you're like me that'd make you very skeptical but after doing a few months of research into others who use them, speaking with the tuner himself, and getting plenty of referrals on CA forums SXOC and Driftworks are two notable examples, I was willing to take the risk. Backyard cheapo modding at its very best.

AFRs are good according to my wideband and the car drives very well on and off boost. I wouldn't call it doughy at all, not sure where you get the 10% richer figure from (The RX7 injectors are only 4-5% larger than the GT-R ones that the Remap is tuned for). Do you mean being in the 11s at the transition point? I fiddled with that a little in the SAFC (still wired in but values zero'd as it allows me to watch knock and monitor peak revs etc) and it made no bum dyno difference.

I agree with you completely that a full tune by a good tuner with a Nistune would be superior, but I'm willing to sacrifice 10kw and maybe some response for $600+ saving which would get me 3 more track days or another set of tyres.

Edited March 8, 2012 by ActionDan