Old 05-03-2021, 09:28 PM
FMile Pontiacs's Avatar
FMile Pontiacs FMile Pontiacs is offline
Senior Member
Join Date: Dec 2007
Posts: 170
Default Crank Trigger/ECU Help

I have some problems with a new set up I have been trying and no one local has been able to help much with it. On our drag car, the 1964 GTO, I have been trying to upgrade and use an ECU (Engine Control Unit). I purchased a new MegaSquirt Gold Box from efisource.com. I have a friend that has successfully added it to their car, with a Pontiac engine and it even helped pick the car up some. I have already talked to him and he is at a loss with my problem as well.

Anyway I have installed the Megasquirt (MS3) and I am currently using only a toothed crank trigger wheel as the tach input. I have not yet installed a cam sensor, but will either convert the distributor to use as a cam sensor or get one of those trick Luhn Performance pieces. I am no longer using the distributor to fire the car. I have went with a coil near plug setup using stock GM truck coil packs. The coil packs are the D581 Square coils. I have had the engine fired up and at idle and lower RPM the car sounds great. I revved it in the driveway and it sounded pretty good. I did notice on my laptop that it had a few missed syncs with the crank sensor. Last fall we went to the track to try out the new set up and it ran horrible. Idle and low RPM still sounded great but in the burnout and going down the track it would stutter and sound like it was on a rev limiter.

So I came home and talked with efisource.com and they told me several things to try such as grounds, different crank sensor, plug wires, plugs and nothing helped. At that time I was running a 60-2 crank wheel. I thought that maybe the sensor couldn't keep up with that many teeth, so I bought a 36-1 trigger wheel. The car sounded good and would rip to about 6,000 RPM in the garage without issue. I did have about 5 missed syncs though according to the computer. I thought my problems were fixed but it was too late to go to the track as they had closed for the year. So this past Saturday I went to the track and the car did the same thing. Sounds great at idle and up to around 3,000 RPM then it stutters like on a rev limiter. Seems like it is losing sync again.

So my question for you all is why would I be losing sync this way? Why does it only seem to show under higher loads like burn out and going down the track, as well as when higher RPM zones? Thanks in advance for any help you may give me.

Old 05-03-2021, 09:45 PM
Scott65's Avatar
Scott65 Scott65 is offline
Ultimate Warrior
Join Date: Jan 2002
Location: Houston, Texas
Posts: 1,358

See response in race section.

'65 Tempest 467 3650# 11.30@120.31
The Following User Says Thank You to Scott65 For This Useful Post:

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -4. The time now is 07:58 AM.


About Us

The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.


Cold Case Radiators

Cold Case Radiators is a Max Performance company that produces high end aluminum performance radiators at a price point that won't break the bank. Polished and stamped tanks. 2 rows of 1" tubes. Lifetime Warranty.


GTOG8TA.com is a Max Performance company that manufacturers parts for the 04-06 GTO, 08-09 G8, and 93-02 Firebird/Trans Am platforms.

Copyright © 2017