taylor76zharris

Okay thats what i thought

Alright ive been reading up on converting an f54, p90 head motor to a carb set up. Im unsure the differences in heads. I have read that the p79, p90, and p90a heads have the same valve size, combustion chambers, and intake runners. The exhaust ports differ from the p79 ( they have diamond shaped inserted exhaust runners) head to the p90, p90a. Is this true? Im wondering because i have read the p90 and p90a heads have larger combustion chamber because they were designed for the turbo motor.

What intake will work on the p90 head for carbs? Will the E88 intake fit the p90 head?

Alright will do. Thanks everyone! Hopefully ill be starting it tomorrow, with any luck.

Ok, This is exactly how i have my board wired in minus the tach signal which has been giving me fits from day one, its just confusing to me because the ground and signal wire run in the same sheath and their twisted and foil protected and all that good stuff. My questions/ can i run my sensor returns as shown in this diagram or does each sensor need to have its own separate return ground? Also, am i correct in thinking that the white tach signal is the only wire that gets connected to terminal 15 on the relay board? If so what do i do with the black wire that runs along side it? I have the black wire grounded through the distributor.

Thanks man, i hope so. This is my third complete re-wiring of the whole thing and hopefully its the charm. Not that ill be much help but when is it misfiring, at idle, full boost, or in between?

Awesome thanks! I tried to do my best to get away from any interference with the distributor wire but I understand Noise is a pretty common problem with this type of it install. I hope I get lucky and don't have any but I'm not counting on it. 1 last question on the relay board there is a large port for an engine ground will that take the place of the 5 ground wires in the DIY wire harness? Because I noticed when looking at pictures and when doing some research no 1 has the 5 wires anywhere on the relay board

Oh alright. So could i use one of those pins for the green/black wire on the distributor that has the pull up resistor in line?

I'm reaching the end of my megasquirt install but I've hit a snag. Where is the best place to tap 12 volts for the injectors and for the distributor? I don't want to source 12 volts for them all from the same place and I don't think that's how it should be done but I'm no expert. Also I'm also doing the install with a relay board from DIY autotune. So where's the best place to get 12 volts for the distributor and the injectors and how many times can I tap the same wire for 12 volt? Thank you.

No, i really don't know why it burnt up like that. Im sure i just had some wires mixed up. This is my first attempt at such an in-depth wiring job so i was expecting a few mistakes just nothing this serious

Im just wanting to know if this can be saved. Its never run on a car but this happened as soon as i turned on the ignition. Has anyone ever been able to use a board that has this amount of damage? I know you cant tell if something is burnt internally and neither can i. Any help would be great, Thanks, Taylor.

Thats just how i have it. I think im going to rewire it using the relay board form diy. Hopefully that will help sort out some of my wiring issues.

I did the tests a few weeks ago and everything checked out. However, i need to make sure i have 12v while cranking. How is your coil wired up? if youre using just a single coil that is.

Great thanks for the info! Its nice to know my settings a right or at least close to it. I made the changes you recommended but still no spark. I did some testing and i think the reason my board burnt right there has something to do with the coil wiring. I disconnected the 12v+ at the coil and watched the for smoke and/or arcing on the board (i had the cover off) and saw none. When i reconnected the 12v+ and turned the ignition on there was a faint spark off of the outer-most exposed circuit in the picture. I dont know how to fix this because the 12v i used for the + on the coil came from the fuel pump relay.

Ok we will see if it works. Here is my msq. Let me know if it worked, Thanks L28ET megasquirt MSQ.zip