Modified SQ Ignition Timing

[Funky Phil]

Well I got to thinking about my ignition curve for my white car and my tuner talking about not wanting to go anymore just to be safe. (which I am completely fine with) But hes also not super experienced with SQ's, Hes actually an RX-7 guy. Anyways I know Ive read on many occasion how much these cars LOVE ignition timing. What I want to know is how do I safely find max ignition advance for a given octane?? I want to make as much power on 93oct as I can but dont want to pop the motor due to 2 deg too much. I will eventually be buying alky inj.

 

What kind of timing are the rest of the MPI guys running with larger turbo's and on what octane??

 

phil

 

[gofastredstar]

Hey Phil i did take a look at your map and mine was setup quite differently, but I wont know if its any better until I get the turbo replaced since it took a dump at the dyno. I can post if you'd like when I get back to the house. Oh, and did you figure out how to put the 65k rpm trigger in the FIP ecu. I agree about the 7500 trigger is to high for these cars.

[Technology]

Use a knock sensor. What do you have that reads knock? Anything?

[Funky Phil]

Use a knock sensor. What do you have that reads knock? Anything?

 

Yeah, I dont have anything. I guess theres a start! HAHAHA! Who makes a good one?

Edited February 5, 2009 by phinko

[Maxzillian]

About the best way is to go run the car on a dyno. You can run enough timing that the car will loose power, but not detonate. The happy medium isn't always on the verge of detonation.

 

Now, granted, something like one of those g-force meters that can calculate horsepower would be enough to get a good close ball park, but I think most of them only display peak power and not a power graph.

[Funky Phil]

Well I was hopins somemore modified ignition control guys would hop in here and say what kind of Ign Timing with what oct and turbo/psi/map. It would atleast let me know if Im in the ballpark of what I should be pushin.

[Turbo_Addict]

For me, I had mine at 20 degrees of timing at full boost and that made a ton of power but at the dyno, the guys said they did hear some audible pinging. I pulled out 2 degrees of timing (18 deg) and went with a bigger shot of nitrous and the piniging went away but my power actually went down (but I was too rich on that tune anyways, so not really a good measuring stick). I went back to a middle ground and am currently running the following with no signs of detonation on the plugs and no audible pinging:

 

s16g evo turbo

21 lbs of boost (25 lbs when spraying n2o)

Wiseco 8:1 pistons

5 gals of 93 octane mixed with torco additive = 104 (+/-) octane

Timing under boost (10 lbs all the way to 25) = 19 degrees

 

This seems to be a nice safe amount of timing without suffering any noticeable loss of power. I've always heard that 20 - 22 degrees is good for mildly modded cars, but once you start getting into the big boost numbers, high hp ranges, and also nitrous, to pull a couple more degrees out. I think if you went to 18 degrees, did a pull and everything looked good - bump it to 19 degrees and see how it looks. I wouldn't go past 20.

 

Tom

 

[PDX87Starion]

For me, I had mine at 20 degrees of timing at full boost and that made a ton of power but at the dyno, the guys said they did hear some audible pinging. I pulled out 2 degrees of timing (18 deg) and went with a bigger shot of nitrous and the piniging went away but my power actually went down (but I was too rich on that tune anyways, so not really a good measuring stick). I went back to a middle ground and am currently running the following with no signs of detonation on the plugs and no audible pinging:

 

s16g evo turbo

21 lbs of boost (25 lbs when spraying n2o)

Wiseco 8:1 pistons

5 gals of 93 octane mixed with torco additive = 104 (+/-) octane

Timing under boost (10 lbs all the way to 25) = 19 degrees

 

This seems to be a nice safe amount of timing without suffering any noticeable loss of power. I've always heard that 20 - 22 degrees is good for mildly modded cars, but once you start getting into the big boost numbers, high hp ranges, and also nitrous, to pull a couple more degrees out. I think if you went to 18 degrees, did a pull and everything looked good - bump it to 19 degrees and see how it looks. I wouldn't go past 20.

 

Tom

 

This is just speculation but it seems to me having the same timing under boost a 10 and 25 psi means that it a compromise and you might be losing some power when at low boost which could hurt spool. If 1 degree retard per PSI is accurate, then at 10 psi you should be able to run about....well, a good bit more advance than at 25psi which should help down low.

 

[Turbo_Addict]

This is just speculation but it seems to me having the same timing under boost a 10 and 25 psi means that it a compromise and you might be losing some power when at low boost which could hurt spool. If 1 degree retard per PSI is accurate, then at 10 psi you should be able to run about....well, a good bit more advance than at 25psi which should help down low.

 

Well maybe I am not doing my conversion from kpa to boost very well. Here is what my settings are currently:

 

http://www.26liter.us/gallery/albums/userpics/10171/ignpro.JPG

 

It seems to pull strong along the whole range - maybe when I am pulling 16 degrees is closer to 15 psi?

Any suggestions on how to make it better and I am all for it. I'm an amateur when it comes to timing, just read a lot and tried to make 'safe power'.

 

Tom

 

[JamesR]

Phil, is your car the one at Ludwig motorsports?

[heefner]

Phil, is your car the one at Ludwig motorsports?

Gt35r turbo with 93 octane I don't go much over 25 psi with 21 deg timing. I'll add half 104 octane and run up to 28-30 psi with the same 21 degrees. I use the same method when I dyno'd my car. Slowly increase timing until I start to loose power or hear detonation. I run water injection too but only as a safety measure. I can run the same tune with or with out the water. My static compression is around 7.5:1 right now.

[Funky Phil]

Phil, is your car the one at Ludwig motorsports?

 

 

Ludwig Motorsports??? No, its in my garage.

 

Thanks for the info Tom/Heef! I dont think Im running nearly as much timing as you Tom. How do you copy that?? My ignition table is miles different than yours!

 

Mine reads across like this:

 

rpm/deg....psi/deg

1000/8......40/+6

2500/18....60/+4

3500/24....80/+2

4500/32....100/0

5500/32....140/-2

6500/30....160/-5

 

Static is 45

 

If im right, I am WAY lower than you!

 

phil

[Turbo_Addict]

Ludwig Motorsports??? No, its in my garage.

 

Thanks for the info Tom/Heef! I dont think Im running nearly as much timing as you Tom. How do you copy that?? My ignition table is miles different than yours!

 

Mine reads across like this:

 

rpm/deg....psi/deg

1000/8......40/+6

2500/18....60/+4

3500/24....80/+2

4500/32....100/0

5500/32....140/-2

6500/30....160/-5

 

Static is 45

 

If im right, I am WAY lower than you!

 

phil

 

Wow - totally different readings, thats for sure. I think where you have your distributor locked is opposite of where mine is locked, that may explain the difference in static timing. When you hook up a timing light, is it jiving with what the computer is reading? They should be identical - 18 degrees of timing on the mark should show that on the computer when you pull up the 'dash' screen in ignition pro.

 

Also, the psi readings - I know that 200 kpa is somewhere around 18 lbs of boost, give or take a little - so that means that 160 would only be around 12 or so? My highest psi # is 250 which should be somewhere in the low to mid 20's lbs of boost. I'd think you'd want to bring your psi #'s up into that range, especially with that turbo and where you want to be running. And for me - I set it to always be pulling timing out, so at the lower rpm and boost, I have my base timing to where I want it to be, and it doesn't add any timing, only pulls timing out under boost. So where you have 1000/8 40+6, you can go 1000/14 85 / 0. Know what I mean? So basically, 85 under psi is very little boost, maybe a few lbs and I don't pull any timing out - not until I start to get closer to 5, 10, 15, etc does it pull timing.

 

You can always plug those numbers in and see how it runs - it may not work for you, it may help ya. Its hard to tell, seems like every one of these cars likes something different - but when it comes to timing and pressures, they 'should' all be somewhat similar. But the biggest thing is make sure that your timing light matches exactly to what your laptop reads in ignition pro - cant stress that enough.

 

[Funky Phil]

Yeah, timing and the light match. It was the first thing we checked once I hit the dyno.

[Funky Phil]

So, with matching light and computer Im putting a max of 21deg timing under boost on 93oct with low 11afr.

Problem that Im having is a high EGT reading under highway cruising. like 1400F I would like to be more like 1200F and below but thats just what I assume.

Sooo,

How do I find my proper cruising and WOT EGT?

What is causing the high EGT? Too much timing or not enough?

And with light load cruising what should AFR's be? Im seeing low 14's to low 15's AFR.

 

 

Now, I had a chugging/hitching issue while cruising and fixed it with fuel map adjustments. Does that mean I should put more timing into it at low throttle?

 

phil

[Funky Phil]

Also, the conversion is (**psi x 6.9=kpa)

[Maxzillian]

Aside from setting lean (which under cruising 14.7-15 is just about right), having your timing retarded too much will lead to high EGTs. At cruising speed, how much timing are you running?

[Indiana]

I didn't see anyone yet mention base timing. First thing would be to at least chart the stock dist and plot a graph for that. A stock setup has the vac adv and a knock sensor, you should make a graph for that then consider your setup. The ignition maps you showed, that doesn't include or hasn't shown base timing or trigger offset. Without those additional two numbers they have no meaning and are just confusing the rest.

[scott87star]

I was talking to the guy with the other trailered white Starquest at the Nationals with MPI, can't remember his name. Anyway, we were talking timing and he said that advancing timing put the heat into the engine while retarting timing put it into the turbo, his point was that the engine is designed to take the heat and the turbo is not. Therefore having timing too retarded is doing its own kind of damage, like high egt's because instead of pushing burnt mixture into the turbine and out the exhaust you are pushing burning mixture into the turbine and out the exhaust. Does make sense. I also recall one of Chiplee's threads on cam comparisons where he mentioned being conservative on the timing and Shelby stated that conservative timing was just as hard on the motor as too aggressive timing. None of this helps you with exact numbers, I suppose each motor is a bit different.

 

Scott

[Funky Phil]

what do you mean base timing? Im running 15deg at idle with no offset. what the Ecu says is what it is.

I could swear my timing is too high but when i pull a few deg it wants to buck under load. If im reading the programmer right im scheduling 26deg @ 127kpa @ 5500rpm. When i set it to what should be 20deg it bucks. But I cant log ignition and havent had someone watch the laptop while im driving. That my plan to see if Im truly getting that high.

Edited October 5, 2009 by phinko

[Technology]

So, based on your calculation, 127kpa is 18.4 psi. on gasoline my car was running well with about 11-12 degrees at that much boost. I haven't downloaded my e85 map yet, so I can't tell you what kind of timing I'm running.

 

I never answered your question about a good knock sensor to use. I will be switching to a 3000gt knock sensor before my next tuning session. I use a GM unit right now and it's so quiet, we can't really tell if it's knocking or not. But the tuner uses another sensor wired to a small amp and listens on headphones, and he heard knock when my sensor showed small spikes, so it was working. Just VERY quiet. the 3/s one will have more noise, but it's also easier to set a threshold for knock detection that way. You could try the headphone method, do some pulls and listen for loud noises. He used some bosch sensor, but I suppose any one would work. Just not GM.

 

Personally, if I was running that much boost on pump gas with a setup like yours, I'd want some way to log knock. I would consider it one of the two major feedback signals, the other being the wideband.

 

Set your cruise AFR's for 14.7-15, and you could probably go as high as 30 degrees of timing, though I would try 20-25 first. If you are going for a specific EGT, you will have to mess with fuel and timing, I'd think.

[Indiana]

Base timing isn't in the ignition maps of the stock ignition curve and its not in MS that uses Megatune either.

 

Stock c/s at 5500 rpms and full stock boost is 10+34-7

+10 base

+34 mechanical advance

-7 boost retard from the vac adv

 

if the knock sensor goes off the ignitor pulls back 7 more

 

if your knock sensor is BAD and you don't know that and you set base timing then the ignitor won't do anything, it can't you already adj. its limit of correction out.

 

If the vac adv and the knock sensor is bad and base is set at stock its +10+34 and that's where the motors blow headgaskets and melt stock piston or forged it won't matter and its all sorts of strange assumptions

 

Forged motor, MSD box that replaced the knock box, base of +10 plus mechanical adv of +34 =blown motor, head scratching...what happened?

 

stock set up, base +10, mech adv +34, boost retard -7, senses knock -7 = ~30

So why are your ignition maps so conserative? Even a stock set up that doesn't sense knock and boosted upwards of 30psi is still running ~37 advanced at high rpms.

 

You might to get some EGTs before you start to play any further.

[Indiana]

Part II

 

Cam timing. -or in other words the relationship of the ignition event timing to the pistons because the dist. is driven from the cam so an out of "time" cam means the ignition is off from the position of the piston. Non degreed motors are lacking full potential even if you just have your head cleaned up with a light cut. Read the manuals, the limit of the two combined surfaces and what can be removed is only .008 You cut about three times that away just to get a zero deck. If you aren't using a dist. or sensor for ignition driven from the cam then its reading the crank position I'll assume and if you didn't degree the cam and the surfaces are cut down you might as well just use a cam from a Ford or a Chevy because its so wrong...

 

read this...

http://kb-silvolite.com/article.php?action=read&A_id=34

[Funky Phil]

Not sure how to get my base timing for you since the car wont run without the ECU? So your saying under boost my timing is fine??? Just seems like alot. And, my car is running a locked out distributor with computer control and no knock sensor. Just my eyes on the plugs. Also under boost Im seeing 12-1300deg on EGT.

And I agree, I need to degree the cam. Ive got the blockdecked and the head skimmed.

[jahjah]

So, based on your calculation, 127kpa is 18.4 psi. on gasoline my car was running well with about 11-12 degrees at that much boost. I haven't downloaded my e85 map yet, so I can't tell you what kind of timing I'm running.

don't forget to subtract ~99KPA for normal atmospheric pressure, 127 kpa is more like 4psi of boost pressure

 

I was always told that when you dyno the car and pull timing until it knocks then push it back a bit was the WRONG thing to do. you might just need to travel a bit to find a more experienced tuner.

 

Good luck