MicroSquirt.com read only forum (Jan.15,2018)

Hi Folks,

First of all, before I go to far... I am a transmission shop owner in Tampa FL and not much of a tuner so please forgive me for my ignorance!

A little info about my setup...

Chevy Bowtie Sportsman block (383 cubes)
Callies Dragonslayer crank
Callies Compstar rods
JE forged pistons 8.5:1 CR (31cc dish)
Comp Cams turbo grind from C-Motorsports .561/.561 224/227 114 LSA
All ARP stud fasteners
SCE Titan ICS head gaskets
Dart Pro-1 Heads. 215cc runners 64cc chambers 2.05/1.6 valves Ported.
Accel Intake. (Looks like a Victor intake with injector bungs.)
Precision Turbo Elbow
Accufab 90mm throttle body
Siemens 83 lb/hr injectors
Aeromotive A1000 Fuel pump
Aeromotive fuel pressure regulator 45 psi
Dash 8 lines in, dash 6 lines out.
Turbonetics T-76 Turbo .96a/r
Turbosmart 38mm wastegate
Spearco air/water intercooler. (no water lines hooked up yet.)
Driver side header with 1 5/8 primaries and 2.5" collector
2.5" crossover pipe
Passenger side log setup 2.5" and a T4 flange at the front. (copied Parish!)
Spark Plugs are NGK R5671A-8 Gapped .035"
Ford EDIS-8 Wasted Spark Ignition sytem
MSD DIS-4 Ignition box
Precision Industries Vigilante 3800 stall converter
700 R4 Transmission
3.73 Rear gear
4300lb 96 Chevy Pickup

MEGASQUIRT II. Version 2.2 board. V

Ok... I managed to get it running and idling quite smoothly. AFR at Idle around 14.0 Although it seems like it better when it's slightly richer. When it first ran, the headers glowed red hot at an idle. You could almost see through them. I was told it was that the timing was too retarded so we cranked up the timing and the headers cooled right down. We are running about 42 degrees timing at idle.

Driving around town seems to be ok with a slight miss now and then. We're running about 36 degrees timing at cruise and an AFR of about 14.5

We have not completed the intercooler water hookup so we are basically non-intercooled right now. We have a 7lb spring in the wastegate and it will see no more than 8psi under high throttle.

I cannot open the throttle all the way because it breaks up bad.

If I progressively open the throttle, it will build boost and pull ok, but you still see a miss while under boost. It does not make the power it should. Under boost I am seeing a 12.8 AFR and a total advance of 30 degrees.

I took it to the eigth mile to see what it does. It was a sad display. The first run was 8.60's at 85 mph. UGH! SLOW!! I talked to a Grand National owner and he said that I was running WAY too much timing. He said that I should run no more than 26 degrees. So I turned the timing back and took another run. SLOWER this time. 8.90's at 82mph. It broke up more than it ever had.

Turned the timing back up and went to 32 degrees. (under boost) and it pulled better and got an 8.70. It broke up a little less, but still broke up some. AFR's were still in the mid to high 12's. I removed a plug and it looks a bit black, but not wet. Also, this thing is a fuel PIG!! It's getting roughly 3 miles/gallon, but I don't see any black smoke pouring out the back.

Everything I read about turbo's say I am running too much timing. I am wondering if there is a calibration problem with my timing control. It seems to like it when I turn the timing up, but I am scared to keep going and break something. The plugs do not show any hints of detonation. I haven't heard any pinging while it's under boost. Is there a possibility that my timing light is showing an erroneous reading due to the wasted spark system?

I also seem to have a bit of a problem with accelerator enrichment. It tends to bog a bit when the throttle is first openned, especially if openned aggressively. I have to roll into the throttle. The accelerator enrichment seems to be delayed a bit. When I look at the datalog, there is a moment of lean condition right after the throttle is openned, and then a rich condition. It should never lean out on throttle openning. It's only for a split second, but I know it's not right. If I make the response more sensitive, it launches better, but it has a bad side effect. It seems to go into accelerator enrichment mode while cruising and causes misfires.

I realized that this was occuring due to fluctuations in the Map reading so I moved it to pure TPS enrichment. I no longer get the accel enrichment while cruising, but it seems to not be sensitive enough. I still get that slight bit of leanness right after openning the throttle. I thought I should see a moment of richness and then level out. I can't post my msq file right now because it's on another computer. I will see if I can do it tomorrow, but for now... here's my accel wizard settings...

Tps Based 100%
Rate MS
220 6
140 5
80 4
40 2

MAP Dot Threshold 100 TPSdot Threshold 2.0
Accel time 0 Decel Fuel amount 30
Accel Taper Time 0.4 Cold Accel Enrichment 9.0
End Pulsewidth 2.0 Cold Accel Mult 100

My Required Fuel is 7.4 and I read where Lance said you shouldn't have more than your required fuel for accel enrichment. I don't think I have a problem with the amount of fuel that it sprays. I think I have a problem that it's just a bit delayed.

My other problem is that it blows exhaust gaskets all the time. I was using FelPro 1405. It is the only available exhaust gasket for my heads. It blows them in about 20 minutes. I tried using SCE exhaust gaskets, which had to modify and they worked about a full day, then blew out. No one else makes gaskets for these heads and I am contemplating fabricating some exhaust gaskets out of alluminum. Running out of ideas!

Any thoughts or suggestions will certainly be appreciated. Don't beat me up too bad. I know I'm ignorant. Trying to learn something new. I hope I have supplied enough information for someone to envision my setup. Thanks.

I'll try and post a log tomorrow and my msq file. I need to hook up an external drive or something to my laptop. (It's not allowed on the internet.)

Fernando
Transmission Physicians
Tampa, FL

Fernando,

You will probably want to richen the idle up and pull some timng out. With that cam (which is similar to what I run in my 406), you'll probably need to run around 13.1-13.5:1. In any case, don't set the idle by AFR, set it to minimize the idle kPa at your desired idle speed, regardless of the AFR.

Have you verified the timing in MegaTune against a timing light? Are you sure the mark on the damper hasn't moved (it won't if it's a fluiddampr or something similar, biut it might if it's a stock unit).

12.8:1 is likely too lean under boost, increase your VE entries at MAP values over 100 kPa by about 5% to 8%.

Unless you are spending a lot of time WOT, it won't affect your mileage much, this is much more a function of the cruise settings. You should be able to get your cruise AFR to at least 16.0:1 and maybe even 17.0:1. And you can use more advance at cruise, up to about 42°-45°. That will hep the cruise economy a lot.

Don't use aluminum for exhaust gaskets, use dead-soft copper, it has much better heat resistance. However, richening up the idle and pulling out some timing will cool the headers in any case.

When you post a datalog, we'll have a closer look.

Lance.

About your exhaust gasket, my mechanic swear with the high-temp black silicone for the exhaust gasket..

He do all of the car he work on with that and it seems to hold up just fine!
At least, it was holding up fine on my old mustang five-oh.

First thing I would do is make absolutely sure your timing is correct and functioning properly.Everything in your post is telling me that something strange is going on with your ignition setup (glowing headers,42 degrees a @ idle,popping,poor milage,poor power,etc) I have never used a wasted spark setup but have been told that the electronic dial back timing lights can give incorrect readings due to the wasted spark, verfiy using an older style light (non electronic).

Brad J.

PS: about your exhaust gaskets.. I run felpros, never had a problem (homebuilt twinturbo system).Is the trouble side the log manifold? are your mounting bolts a loose fit? apparantley the log style manifold is especially bad for warping when they heat up, elongating the mounting holes helps to allow some movement and reduces the stress.

PSS: 700 R4 EH?? Your really going to test your tranny building skills when this puppy starts working ..LOL