Help with idle on Mamo NA 434 build.

[zaxrx]

I have exhausted my efforts with trying to get this car to idle correctly. I have to give it pedal to start and it stalls most of the time, hunts, etc. I can get a semi decent idle if I bump the RAF table up. As soon as I add the proper RAF it will not idle. Set timing at 28 degrees in the idle areas, halfed the over/under timing along with the other tricks mentioned in the Idle thread.

There is someone who is going to help me but he is very busy and I am extending the offer to someone that I can pay to help me.

My mod list is: Stroked 434,(7.2L) built from a re-sleeved LS2 block,Mamofied ported FAST 102 intake and throttle body, ported AFR245 heads, 247/247 .623/.623 114 cam, 1.75" long tubes, #60 Seimens injectors with the correct injector tables running stock fuel system.

Tony Mamo worked with me on the entire build. Tony is an awesome guy and I am very happy with the results so far.

I have the VE and MAF tables tuned what I feel is very close.

This engine is a monster in my 94 RX7. It runs great other than idle. AFRs are spot on.

Let me know if you want to help me out via emailing back and forth and we can work out payment.

[zaxrx]

Also wanted to add that I drilled the throttle blade. It came out of the box with no hole. When it idles, IAC counts are in the low 100's so I should be fine there.

I have the idle timing set at 28 degrees. It seamed to like that the best. All spark tables reflect the same timing values for idle.

Cable driven throttle. M6 with a lightweight flywheel running 3.90 rear gears. Using a PCM from an 02 Camaro with LS1 knock sensors relocated to the side of the block.

All sensors are brand new and reporting properly. Fuel pressure is solid at 58PSI. No vaccuum leaks, TPS voltage is .54 volts...

[Ben Charles]

I sent a PM, but now I see your setup (should have looked first)
I'll send you another PM

[Ben Charles]

This thing should be up and running strong in no time

[hymey]

Way to much idle timing for that cam which is relatively mid size, I run bigger cams then that 15-20 degrees idle with plastic intake. I would say, possibly not enough idle air, to much timing, hunting can also be to rich. Correct idle afr with a cam like that will be leaner then 15:1, as air is sucked back in on overlap. I have ran upto 266-270@50 with less then 20 deg timing on a plastic intake. Get IAC down lower, but you want it idling correctly hot with no IAC help at all (no correction) before you even think of turning correction back on. 28 deg timing is silly with that combo at idle.

[Russ K]

Had an aluminum flywheel in my 418 for less than 2 months. Could not tune out the idle hunt/surge & stalling. Swapped the stock flywheel back and no more issues. Light weight flywheels are NOT for street driven cars!

Russ Kemp

[PAT WS6]

Had an aluminum flywheel in my 418 for less than 2 months. Could not tune out the idle hunt/surge & stalling. Swapped the stock flywheel back and no more issues. Light weight flywheels are NOT for street driven cars!

Russ Kemp

this is not true.