Adding EFI on Stock Motor

[NeverSatisfied]

I presently have the '76 302 in my truck but I plan to add the EFI bits I have accumulated over the last few months.

I was wondering what aftermarket cam I should install to obtain HO firing order. I don't need anything radical w/ my 150:1 crawl ratio, I just want the cheapest way to get the injectors firing at the same order as the ignition and valves.

Thanks for the input.

 

[ponch0v]

Just finishing up my EFi/stock block install. I used a stock 351w cam. Ran the windsor cam in the motor prior to the EFI install. I felt the motor ran a bit stonger with the windsor cam.

My install is complete and I will fire the motor tonight! ;D YEEHA

 

[NeverSatisfied]

are there any problems with engine balance once you change the firing order (damper, flywheel)

 

[Broncobowsher]

are there any problems with engine balance once you change the firing order (damper, flywheel)

No problems with balance. You are not moving any mass in the bottom end.
Windsor cams work just fine for changng the firing order.

 

[CRZA1]

I run the HO firing order with a stock 302 cam, and it purs like a kitten. Nono of the rough idle people talk about or anything wierd. It made the engine run stronger and it feels like it picked up some torque. Left the injectors alone and wired stock, and wired the engine to the stock firing order. You may want to change it anyway but it works really well for me without.
Good Luck

 

[66horse]

I run the HO firing order with a stock 302 cam, and it purs like a kitten. Nono of the rough idle people talk about or anything wierd. It made the engine run stronger and it feels like it picked up some torque. Left the injectors alone and wired stock, and wired the engine to the stock firing order. You may want to change it anyway but it works really well for me without.
Good Luck

Ditto here.

 

[Socal Tom]

I've said it before and I'll say it again. You don't need to change the cam or the wiring in the harness. It works fine.
Tom

 

[SaddleUp]

I've said it before and I'll say it again. You don't need to change the cam or the wiring in the harness. It works fine.
Tom

That's been my experience as well. I didn't notice any change in the idle when I went from the SD ECM to the Mustang MAF ECM on the original 5.0 I had in mine.

 

[NeverSatisfied]

I've said it before and I'll say it again. You don't need to change the cam or the wiring in the harness. It works fine.
Tom

I keep hearing this. It makes me a little nervous, but it seems like no one has any problems at all in doing it. I guess I'll give it a shot w/out the cam swap

 

[A&Mbronco]

Did any of you guys change the pins at the computer? I did this and seems like my engine is running rich, not sure if thats the problem or possibly need a new MAF sensor.

 

[gear_head]

I just completed my conversion a few weeks ago. I'm still working out a few bugs but I think it is fundamentally a solid setup. Personally, I didn't like the idea of injectors firing at the wrong times, but I can concede that it probably doesn't make a huge difference either thinking about it...
I switched the injector order in the harness to match the non-HO firing order, and run on only one O2 (signal goes to both sides). This seems to work really well, the idle is very smooth. This way, injectors are firing when they should be. My friend ran his this way for years on the original block.

 

[COBlu77]

I used a Summit Racing 351 W cam, but I would go with a stock 351W cam or just leave the non HO 302 cam in there. My Summit cam and lifters were about $80. The Summit 351 W cam is the same grind as the Edelbrock Performer and several other cams sold for one step up in performance. It seems to lack a little on the low end, and really doesn't come to life until it gets over 2000 rpm. Not bad, just a small difference from the Erson RV cam I had prior to my EFI conversion. Otherwise, it idles smoothly and runs well. I believe the Summit cam is just a little too much and a stock grind would work better for low end torque.

After studying how the SEFI MAF computer and O2 sensors were designed to work, I opted to change the firing order to match. I figured that I was half way there anyway with the intake off and didn't want to have to take it all apart again if I wasn't happy.