302 351 swap
#1
302 351 swap
Hi ive got a 1987 f i50 that had a 302 efi, i swapped it to a 1994 351 efi . i used the 302 wiring harness, chaNGED the ecc to a 1988 351 efi and took the shaft from the 351 distributor and changed it with the 302 shaft and now running that 302 distributor with the 351 shaft in it. the motor just wont run. any ideas , anyone do a similar swap. also what controls the firing order.
thanks
thanks
#3
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Help...from other members on this one:
Hi ive got a 1987 f i50 that had a 302 efi, i swapped it to a 1994 351 efi . i used the 302 wiring harness, chaNGED the ecc to a 1988 351 efi and took the shaft from the 351 distributor and changed it with the 302 shaft and now running that 302 distributor with the 351 shaft in it. the motor just wont run. any ideas , anyone do a similar swap. also what controls the firing order.
thanks
thanks
All I can tell you for sure on this one is that the firing order is determined by the distributor. Set the engine up at top-dead-center at cylinder #1, both valves closed, and be sure the rotor in the distributor points to the wire going to #1. The firing order for the 351 is 13726548 and the 302 is 15426378. The order should be annotated on the intake manifold casting. (The different firing order for the 351 takes power load off the front main bearing.)
I'm thinking as well that the system is not compatible with the '88 ECC and all the various sensors used on the 302 will have to be carried over to the 351. The two engines are essentially the same except the 351 has a higher deck, a heavier crank and a different firing order. I'm not sure if the intake manifolds will interchange; if they do, then use the whole intake system from the 302 on the 351 or at least adapt the throttle body from the 302 to the 351....all with the idea of preserving the original sensor configuration so the ECC will know what's going on.
Anyway, get the firing order straightened out....it could be the major, if not the only, problem with the failure to start.
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Apples and Apples:
If you were able to fit the 302 distributor onto the 351 it should work, but with the original ECC....unless the '88 ECC is a direct replacement for the '87; it may not be.
If you connected the plug wires the same as they were on the 302, then the firing order is wrong.
The initial timing could be way off unless the 302 distributor and its drive shaft were installed and positioned exactly as they were on the 302. The only way to be sure the initial timing is right, as I mentioned before, is to check the rotor position with #1 cylinder at compression-top-dead-center.
If you connected the plug wires the same as they were on the 302, then the firing order is wrong.
The initial timing could be way off unless the 302 distributor and its drive shaft were installed and positioned exactly as they were on the 302. The only way to be sure the initial timing is right, as I mentioned before, is to check the rotor position with #1 cylinder at compression-top-dead-center.
Last edited by Kattumaram; 06-24-2009 at 08:10 PM.
#6
Ive got the wires on right and i set the the timing with it at top dead centre comp and nothin, could it be the injector wiring harness off the 302 that i used on the 351. im also using the 302 coil and the sensors or what ever is connected to it to.
thanks
thanks
#7
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All used up:
I'm fresh out of ideas on that....the best I can offer is for you to revert the entire electronic interconnecting system to the 302 configuration that you had....except for the firing order.
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#8
We put the plug wires on according to the 351 firing order. The intake wont fit cause the 351 is a tall deck and about 2 inches wider. The injectors are original to the 351 but the injector harness is off the 302 due to the connector being different. To make the 302 distributer fit i had to change the centre shaft with the 351's. So the electronics inside the distributer are 302. I changed the computer(from an 88 351) so it would have the right timming and fuel delivery, also because of the different firing order im guesing the computer is controlling the injectors with its preprogrammed firing order. So thats why i thought the computer would fix the problem but no luck. The sensors i guess could be an issue but its getting good spark so i think it might be a fuel issue even though i got fuel at the rail.
Anyways right now im stumped and the only thing i can think of is the distrbuter so thats about it. Thanks, Chad
Anyways right now im stumped and the only thing i can think of is the distrbuter so thats about it. Thanks, Chad
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Of no effect:
Fuel injection for the engines is not timed-sequential (at least for a '94). Each bank of four injectors is simply fired alternately every revolution of the engine and it really doesn't make much difference where in the crank rotation the injection occurs so long as the required amount of fuel is at each intake valve; so, sparkplug firing order won't affect fuel injection at all.
I'm still of a mind that the '87 harness and '88 ECC in combination with '94 engine sensors have compatibility problems that have yet to be addressed.
Dam*!! I wish I had my '82 VW Rabbit diesel 4-speed back!!
I'm still of a mind that the '87 harness and '88 ECC in combination with '94 engine sensors have compatibility problems that have yet to be addressed.
Dam*!! I wish I had my '82 VW Rabbit diesel 4-speed back!!
Last edited by Kattumaram; 06-25-2009 at 03:44 PM.