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Modified E31/F54 on stock S130 EFI?


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I'm wondering if there will be any issue using a modified E31 head on an F54 block in an '83 280ZX with the stock EFI. I know the stock EFI doesn't like a agressive cam but would this E31/cam be mild enough to run on a stock EFI? I searched but I didn't find anything about the stock EFI having issues with the higher CR or the larger valving on the modified E31. Any known issues?


Also what do you do with the head temp sensor - just leave it dangling? Does this cause problems because the ECU thinks the temp is too low on the head?


The E31 specs:

Some porting (mild)

1.73 intakes

1.378 exhaust ?

Heavier Roadster Springs (U20?)

200 thou lash pads

Run 25 lbs fuel pressure (not sure what this info is for)

Distributor- total advance 38-40 degrees (not sure what this info is


3-4000 miles on Shadbolt M445 Cam


Shadbolt M-445 cam specs: Duration: 280 degrees, Overlap: 60 degrees, Lift: 0.507†at the valve

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Yeah that cam would be very excessive for stock efi. Megasquirt would probably be an option. The only other problem with the setup is that these motors due to combustion camber size cannot take a lot of compression without detonation. With a 1mm headgasket you would have 10.433 compression...So you would probably want to run a 2mm headgasket which would yield you 9.406:1 comp. unless this car is gonna be a track car with high octane fuel of coarse. Also the e31 head doesnt have injector notches in the intake runners and they will have to be drimeled in, and as for them running 25 lbs. of fuel pressure they must have been running a 4 barrel car of some type(su's only need 5-7ish)


Oh and for reference http://www.ozdat.com/ozdatonline/enginedesign/

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Doh! Forgot about the injectors. Sounds like the spare F54 NA block and the E31 would be a good combo for my 240Z instead of putting it on the 280ZX. I could just take the intake/triple Mikuni's of the current engine and put it on the F54/E31 and run that in the 240Z.


I've got a line on a L28ET/ECU/Harness so I'll just patch the N/A setup for now with the P79 and do the header and exhaust while I've got the intake off.


Thanks for the help again guys - I like to do as much research as I can before jumping in!

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