Don Terrill’s Speed-Talk

I'm fairly new to this forum, but I am building a 1987 jaguar XJS, with a five speed conversion, and after spinning a bearing in the original motor, i built a 6.5 liter stroker motor, by using overbore sleeves 96mm, custom pistons from Ross, i offset ground the crank .180 thousandths and used manley sportsman 6.0 rods with chevy 229 main bearings.

now that the motor is assembled I'm trying to figure out how to run the engine management.

i need a system that can sequentially or batch run 8 injectors, and i don't really have the access to a dyno,
so plan was to run the original distributor with the aftermarket craine optical trigger, and run two self tuning systems from F.A.S.T. one for each side of the engine.
does anyone know if this would actually work?
my main concern is that the systems wont tune the motor equally.

any feedback would be great,
thanks,
Calvin Silbernagel

Have you looked at Megasquirt ?
It will handle 12 cyl batch or sequential.

MegaSquirt can do anything.

The tuning software is also nicer than the XFI package.

I've yet to see a "self tuning" computer. They never get the critical acceleration enrichments. They will self tune the VE map, but that's the easiest part of tuning.

Heard the latest Pectels do V12's too.. buddy uses one for his Testarossa.

The holley dominator ecu has 12 injector drivers and can control 12 coils as well, + dual wideband controllers. Theres quite a bit of choices depending on your budget that will work without needing to run two systems.

putting the injectors out there with the throttle body may defeat the object of injection, especially with the convoluted manifolds you have on the jaguar, fuel will drop out of suspension.

don't the fast system have the injectors in the throttle body.

Calvindoesntknow wrote:so plan was to run the original distributor with the aftermarket craine optical trigger, and run two self tuning systems from F.A.S.T. one for each side of the engine.
does anyone know if this would actually work?

Don't even think about that, it's pointless and complicated with no justification.
If you're new to EFI and want to do this yourself, starting with fuel only and batch firing injectors could keep it simple enough for you to handle and get running.
I have no idea where you are because you didn't fill out your location so it's hard to recommend anything more to you based on support and dealers.

Rizzle wrote:The holley dominator ecu has 12 injector drivers and can control 12 coils as well, + dual wideband controllers. Theres quite a bit of choices depending on your budget that will work without needing to run two systems.

Do you have experience with these? I know their website says 12 inj and 12 ign but I don't see that when looking at the limited documentation. I tried to call them and ask but they wont call me back so I wrote them off.
The idea of 12 cylinders seems way out of line with their catering to the mass domestic V8 crowd, I don't understand why they "claim" that capability.

You can download the holley software for free. I believe the software is the same for hp vs dominator just the dominator has a few more menus but i only see cylinder select for up to 10 cylinders

In the HP/Dominator wiring manual cyl 1-8 (A-H) are accounted for in the P1A P1B connectors to allow interchangeability between the two ecu's (wiring on those two plugs is identical for both systems) and there are 4 more (I-L) for both coil (EST output) and injectors on P2B, which is a dominator only output harness.
I have played around in the software a little but have not had the opportunity to actually use one of these ecu's. Dieselgeek may have iirc.

Rizzle wrote:In the HP/Dominator wiring manual cyl 1-8 (A-H) are accounted for in the P1A P1B connectors to allow interchangeability between the two ecu's (wiring on those two plugs is identical for both systems) and there are 4 more (I-L) for both coil (EST output) and injectors on P2B, which is a dominator only output harness.
I have played around in the software a little but have not had the opportunity to actually use one of these ecu's. Dieselgeek may have iirc.

I've used a number of HP and Dominators now. I like them. Holley went through the trouble to create really excellent documentation, something missing from many other electronic controls out there. I know they have enough outputs for 12 cylinders but not sure they have the ability to control them. I think their intention was for staged injectors (multiples per cylinder), but I would need to confirm.

Meanwhile, for v12 application, there are a ton of guys running Megasquirt. Lots of reading you can do on the subject. If you use a distributor it's a no brainer in my opinion. You'll find more v12 users there than pretty much any other ECU I think. A number of Merlin and Allison V12 tractor pullers are running them successfully.