an 86 would have had the 287 G- head as the swirl head didn't come out till 87. a G head gives a lower comp ratio so they like bunch more timing advance compared to the swirl head. I would just start bumping the timing up a bit at a time but I don't currently have a knock sensor so I am very wary of advancing timing until I have knock sense capability.
I'm hardly an expert on what head was used on what car; but according to AllPar, the 86 GLHS used a FB head.
Rob,
You are correct, the 86 GLHS was built with a "fast burn" head. I actually gave up using a G head on my 87 CSX because of all the issues getting a G head to run correctly on a 2.5L. I think I spent a year messing with the G head and still ended up making the car run better with the fast burn head.
Originally Posted by ShelGame
I thought I'd give some more feedback on the cal. I drove the car for a short period last night and besides for a couple misfires, the car ran pretty darn well. Well today I ran 11 auto-x passes with the bricks in my catalytic converter turned sideways, and the misfire was more severe.
The problem seemed to be during transient throttle operations, like coming out of a turn. I repaired the exhaust, and the problem is improved, but I can get the car to misfire once in a while. One thing I noticed is the power loss light comes on some times during the misfire. I have the check engine light on knock detect turned on, so there's a possibility it's timing related, or it could be fuel, or lots of other things.
My plan is to add a boost gauge and A/F ratio gauge tomorrow after work to troubleshoot the issue (and not blow the car up). This might be related to my scaling of the 81 lb injectors, or could be because I set the boost target to 14 psi and still have the 2 bar map. I disabled overboost, but I didn't disable the overboost when the wastegate failure is detected. I'm wondering if I'm getting a spike that is above the map, then the car is shutting me down for overboost because I'm above the target. This might explain the power loss light coming on.
Once I get things straightened out on my end I'll report back with what I had to tweak in order to use such large injectors and cure my misfire.
Really need a wideband on there to really know if it's fuel related. More than likely it is though, if you are running stock Stage II timing maps you shouldn't have any timing misfires if you run 93 octane or better.
I have a wideband, but it killed 2 sensors on my CSX. I'm not sure if it was due to the E85 or because something in the controller is bad. Either way, I used to do lots of tuning with the standard O2 sensor so I'll work on that route before I mess with the wide band again.
I found the logic module pinouts, so now I can hook up my instrumentation and begin the testing process.
If you're familiar with it then yeah you can go off a NB, I've tuned fairly successfully that way, just don't like recommending it to anyone
To my knowledge all 86 cars should have been a swirl head.
check your transient enrichment tables under fuel. best I can do is half of a clue for you to start with.
if I remember correctly, when adjusting tables by injector size, one of the generations of cals didn't include pump shot tables (AESLOP/Delta MAPEnrichment FromTemp2, and POSSLP/EnrichmentFromTemp) in the modified tables (and those tables had to be edited manually). I just opened T-GLHS to compare to my (previous GLHS) settings for the sake of reference. I could find AESLOP but not POSSLP in the directory tree, and the same goes for the list of tables under the scaling tab. I'm pretty sure both need to be scaled or you will never get part-throttle tuned right, took me a long time to realize it. been several years since I ran this module, can't remember how I resolved it, sorry I can't help further.
Ok, I hooked up my A/F ratio gauge and noticed any time I have a hesitation or misfire I'm going full lean. The problem is essentially only light or no throttle to full throttle transients. Since I'm going lean and not going rich, I'm thinking something got scaled that shouldn't have. Any ideas?
- - - Updated - - -
For troubleshooting purposes I will also be turning off anti-lag. I want to eliminate as many variables as possible.
It looks like the PumpShot PW map did not get scaled. My thought is that the pump shot is so large that the engine misfires and I'm getting a lean indication simply because the fuel didn't burn. At least, I'll try scaling this "DeltaMAPEnrichment FromTemp2" table and see what happens.
Back in the old days, I used to go through any table that had a PW axis and scale it for the injectors. That used to work well, so I guess I'll continue with that philosophy until the issue is fixed.
Last edited by jckrieger; 09-17-2014 at 08:50 PM.
The Pump Shot MAP tables are in units of msec/psi (or usec/torr, I think, officially). So, they do get scaled for injectors; but then they get scaled inversely for MAP. If you're scaling for +40's and a 3-bar, the net effect is no change since the 2 scale factors are nearly the same.
You can check to see if they are scaled for injectors in MP Tune under 'Scaling, injectors, tables'. I just checked and it is set to be scaled.
The issue may be due to resolution. The PW change is very small. When you scale for a 3-bar MAP, the PW change per each incremental MAP change (IE, each bit) is 1.5x what is was with the 2-bar MAP.
Of course, feel free to tune as needed.
86 uses a fast burn head.
I'm not sure if this is Turbonator related, but my 2 bar 81 lb/hr GLHS tune is still having an issue. I added some transient fuel enrichment and resolved some of the transient lean conditions, but I noticed a very repeatable 5,000 rpm cutout that occurs both at WOT and light throttle. The A/F gauge shows lean when the cutout occurs, and the car does recover and continue past 5,000 rpm. I added 4% more fuel in the pumping efficiency table at 5,000 rpm and there was no improvement. Any ideas? The car didn't do this with the stock cal and stock injectors. Unfortunately, I changed injectors and went to the Turbonator cal at the same time.
I will be checking the plugs and distributor components tomorrow. I may add a ton of fuel in the upper RPM range and see if it has any effect on this 5,000 rpm "lean" misfire.
I think my issue may be related to the speed/distance sensor. I will turn off the staging limiter feature and report back. One time when I was staging from a complete stop the limiter didn't work, so that tells me there's something going on with the electrical side of things.
Problem solved! I disabled the 2 step limiter and the car runs great. Since the car has a cable speedo, I guess I never knew the speed/distance sensor was flaky. Thanks for putting up with my posts!
This code is really good. I can't wait to relocate my map sensor under the hood and make a 3 bar cal. Maybe this winter the car can get some forged pistons and decent T2 rods.
Yeah my speed sensor wigs out on me every so often. Nothing like trying to take off quick and suddenly banging the launch limiter at 4k in 1st gear lol.
How much interest is there in a GLHS 3- or 4-bar MAP? IE, an On-board MAP? One of the things I've been toying with this winter is to build my own MAP sensors using Motorola internals and my own board inside a stock housing. I know Tom Spranger started to do that a while back, but I think he never made many.
Wow! 4bar! That's really something!
I'm curious if the GLHS code has something going for it above the 87code?
I've always heard it had better adaptives, etc, and requiring two chips seemed to confirm there was something "special" going on, but, not speaking machine, it's always just been speculation ...
Mike
"The Constitution is not an instrument for the government to restrain the people, it is an instrument for the people to restrain the government - lest it come to dominate our lives and interests." - Patrick Henry
Bad laws are the worst sort of tyranny.
- Edmund Burke
No, its pretty much identical to the 87 T2 except that the boost control is only psuedo-pwm. It doesn't run on its own timer, just the system clock. So, its slightly less precise.
Odd. Why's it need that much space /chips?
Mike
"The Constitution is not an instrument for the government to restrain the people, it is an instrument for the people to restrain the government - lest it come to dominate our lives and interests." - Patrick Henry
Bad laws are the worst sort of tyranny.
- Edmund Burke
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