jetlude

iTrader: (9)

Please help.

What would be a reasonable setting for my ignition timing (leading) considering my setup? I will be boosting 13 - 15psi, no higher.

Set up:
FDMotor
Medium Street Port (Pineapple templates)
1000/1600 injectors
Bosch inline fuel pump (40psi pressure)
GT4094R single
FMIC
EMS Stinger ECU

My ECU reads 15* at a little over 10PSI, and the car runs reasonably well, but I think it should pull harder..

I want to raise the boost to more than 15psi (pump gas)

What should my timing be about?

WaachBack

iTrader: (21)

Rule of thumb is dont go more then 15 advance on 15psi on pump gas.

I personally have ran in the 20's before, but I have water injection.

arghx

iTrader: (3)

on normal pump fuel don't expect big increases in power from timing unless the map is way off in the first place

it could be a boost leak, it could be misfire, or it could all be in your head. how "hard" a car pulls is pretty subjective. Even dyno testing is tricky because of variations in dynos and ambient conditions.

jetlude

iTrader: (9)

I am presently at 15* at 10psi . Should I raise the timing a bit to about 18-20* at 10psi and taper it down to about 15* at 15psi boost. Does this sound safe enough?

Trots*88TII-AE*

iTrader: (11)

I think ~17* would be reasonable on your setup for 10 psi, taper it to 15 by 15psi to be safe, and maintain a decent split (10+). That's about where I am without my AI right now on a 35R compressor. S4 though.

Are you getting pretty reasonable AIT's?

Aeka GSR

iTrader: (4)

When we are talking pump gas, is this 91 or 93?

bewtew

iTrader: (7)

prob 89 he's in a sea island

jetlude

iTrader: (9)

I also should mention that I run Zero split timing at all times since me ecu does not support split.

Trots*88TII-AE*

iTrader: (11)

Well, that changes a lot of things. Zero timing acts in a similar way as increasing your leading timing. It makes things very different, you would be best off seeking some professional help for that. Please disregard my advice on the 17* leading, it does not apply to zero split.

arghx

iTrader: (3)

**** man, no split under boost on pump gas?

it'll probably be cheaper/easier to just get an ECU that can control split

classicauto

iTrader: (3)

??????



Now - Doesn't support split as in can't change the value, or it just fires each bank of plugs at the same time, all the time because it only has two channels?

If it were me, I'd be getting an ecu that can control things a little finer then that before doing much more to the car.

If you're comfortable running zero split, you're going to have to really lower the overall advance, and power is going to likely be way down vs. having a proper split capable setup because of that.

If your quest to raise the boost above 15 is in search of more power, I'd suggest first getting a proper ECU and re-tuning the setup at and below 15psi. I can almost garuntee that the advantage of higher leading timing and split trailing timing will raise the power compared to your current boost level with ultra low timing/no split.

jetlude

iTrader: (9)

Actually, thats why I think I should be ok.
And this quote from Racing Beat website lets me know that there are others running without split

Supercharging/Turbo

Supercharged engines deserve special comment. In general, if you are just adding a small amount of boost (low restriction exhaust system), leave the timing at the stock settings. However, if you are porting the engine, running high boost and a large intercooler, or operating the engine at continuous high RPM, consider retarding the timing a bit. In our peripheral port turbo engines, we use 10° BTC total advance, leading and trailing, for dyno development and 12° BTC total advance for racing, after the engine management fuel mixture is well established. The timing is set at 6000rpm and leading and trailing plugs are fired simultaneously. The truth is that the power increase at 12° BTC is small and the danger is greater than at 10° BTC. Each increment in timing increases the risk for smaller and smaller gains in power

Your thoughts ?

hwnd

iTrader: (4)

I think you're going to be just fine not using any split ign.

There is a 20B floating around here who put down over 800hp without using split ign.
I think as long as you pay attention to the knock sensor you will be just fine.

btw, on Sea Island... is race fuel available to you?

Trots*88TII-AE*

iTrader: (11)

Exactly like on the racing beat website, you can run no split, but you have to retard lead (or in this case total) ignition to compensate. Instead of running 16-17* lead timing, you have to drop it down to 10-12*, depending on your fuel, and what works for your engine. Either way, you are likely losing power and raising the risk, since every degree has that much more impact.

jetlude

iTrader: (9)

Yea man.....Like I said, I have been running this ECU without split for about 1 year now, and the car runs well. I now want to raise my boost to about 15psi, but just concerned about where my total timing should be.

seandizzie

iTrader: (1)

https://www.rx7club.com/single-turbo-faq-122/advancing-timing-high-rpm-101226/

READ

https://www.rx7club.com/showthread.p...ighlight=split