EFI Brainstorming

[DoABarrelRoll]

So I am brainstorming about running a LS1 PCM (from a Chevy Express Van) on my gen 1 SBC. The issue I seem to be coming to a stop at is the crank sensor. I know EFI connection makes an awesome setup, but I am not feeling it for this motor.

First thought is crank wheel: I know MSD's crank wheel puts out a 5v square wave that isn't compatible with the PCM. Anyone know about other company's crank wheel setups?

Second thought is dual sync distributor instead of the vortec distributor: I haven't been able to find anyone who has one but doesn't run an aftermarket computer, so I can't verify that the 2 signals the distributor outputs will supply what the GM PCM needs.

Everything past that is "pretty much" figured out.



Just in case you were wondering:

Engine:
standard SBC 350 bored .030 over
Brodix IK180 heads w/ Comp Aluminum 1.6 full roller rockers
Jones Racing Cams ( L/C 110, Duration@seat 280/288, [email protected] 224/226, net lift .536/.528)
Flat top forged aluminum pistons (4 valve reliefs)
Cloyes true double roller and timing cover w/ built in button
Holley Street Dominator intake
Flow Tech long tubes

Best guess at compression ratio is 10.5:1

Lastly - are there any real advantages or disadvantages to using a dual plane intake for efi compared to a single plane?

Thanks in advance
Tony

[MrForce]

LS1 PCM's are looking for a 24x signal (24 pulses per crank revolution) That is hard coded in and can't be changed. One of the advantages of this is that the PCM is updated to changes in engine speed every 15 degrees of crank revolution instead of every 90. Current GM PCM's are 58x for even more resolution.

We have converted dual plane intakes to EFI, for hood clearance reasons, because there was no single plane available for the engine, and/or because the customer wanted it that way. The result is EFI with the rpm limit of a dual plane.

Eight nozzles, end of runner placement, 45+ lbs of fuel pressure and timed pulses "cure" all the low speed problems associated with single plane intakes. Most if not all OEM EFI intakes are plenum plus runner design.


Rob

[DoABarrelRoll]

What I'm finding is the only dual sync distributor out there that outputs the 24x signal is made by AEM... but I can't find the damn thing lol.


I think the gods are steering me towards FAST's XIM system (coil over plug, crank wheel, and cam sync). Plus it will let me keep the carb until I get the resources together to finish the conversion over to EFI.

[EFI69Cam]

The express van with vortec 350 used the 411 PCM with the 4x crank sensor and distrubutor, non COP ignition. Use the vortec or LT1 wheel and sensor