'91 4.3 to vortec 4.3 Ignition question

[Payne]

I have a dead 1991 OMC 4.3 (non-balance shaft)engine. I want to replace it with a Vortec 4.3 long block.

I know I will need an electric fuel pump and a 8 bolt intake manifold, but will my OMC HO electronic ignition system need to be replaced?

There isn't anything wrong with it (that I know about), but I'm wondering about the crank sensor, knock sensor, or some other reason why it wouldn't run the newer engine.

I'm trying to keep this conversion under $3,200 for parts. I can do the swap out myself.

thanks in advance

 

[wca_tim]

Re: '91 4.3 to vortec 4.3 Ignition question

I would have a longblock built with the non balance shaft roller version shortblock with a mechanical fuel pump, add vortec heads, an edelbrock performer intake and an edelbrock 1409 marine carb... it'll make more power and probably be an easier swap... and be well within your budget.

 

[Payne]

Re: '91 4.3 to vortec 4.3 Ignition question

Well, I already have a nearly new Holly marine 650 and a non-balance shaft long block costs more than a Vortec long block.

So if I have to get a new manifold anyway why not go with the newer style block that already comes with Vortec heads?

What I really need to know is if the OMC electronic HO ignition will work the Vortec. That ignition is supposed to adjust the timing through a knock sensor.

 

[wca_tim]

Re: '91 4.3 to vortec 4.3 Ignition question

if you're getting a reman from someone, ask if they'll do the roller non-balance shaft block with vortec heads on it... it'll make a bit more power that way (I went this route) , and your holley is a great carb. Just some thoughts. I'm sorry, I don't know regarding the ignition question.