I have a '85 F150 4x4 NP435 and a very tired 300 six. It has lots of blow by and leaks what it doesn't burn. Hard to kill these things but I do keep a gallon of WalMart oil behind the seat. This used to be just an extra old junk truck, but now is my only 4 wheel transpo (I have motorcycles too) as I had to sacrifice my newer F150 because the wife needed something better, so sold that and got here a new Fiesta.

I picked up a used '88 300 FI engine that looks to be pretty good, and the price was right. I intend to take it apart to inspect, and put it back together with new fasteners and of course convert it to carb - as in pre feedback Duraspark II type and have most of the parts already.

I plan to keep the efi exhaust manifolds and have the correct Walker Y pipe to fit on it, plus know I need to heat the intake and the options there. I've done a lot of reading here and elsewhere and feel I got a good grip on things except for one thing - the head.

I have a good - not sure yr - but non air in head 80s recently rebuilt head with the D chamber. I understand my compression would go down using it on the '88 short block. So, should I use it or the one that's on it now if it passes inspection? I know to use the FelPro (don't have P/N in front of me) vs others that are thicker.

For intake I am probably going to use the stock one on the truck now, but use an adapter and install a rebuilt 2100 I bought for this project. I have a rebuilt stock pre feedback 1 bbl carb as well, along with several non rebuilt pre-feedback 1 bbls too. Like I say, I've been reading and accumulating parts for a while now.

Thanks for the good word!

 

Have you planned how to go about getting fuel to the carb? EFI blocks typically did not have the fuel pump opening cut out, so the stock pump cannot be simply bolted on.
This means you will either need to have that hole added, or go with an electric fuel pump.

Using an adapter to go from a 2bbl to 1bbl intake is not a good idea. The intake will not flow any more air than it would with the stock 1bbl carb, plus those adapters are placed under a lot of stress, so they can work loose or even crack/break.
My opinion, stick with a 1bbl carb, or locate a 4bbl intake and use a 2bbl-4bbl adapter if you want to run a 2bbl carb.

 

yeah, 2x on electric fuel pump I used a Facet Posi-Flo 60104 in mine before switching to EFI (really Really REALLY don't like carbs).

And what Rogue_Wulff said about the manifold. Or go with aftermarket EFI like VEMS or Mega-squirt and a '96 Distributor (Hall Effect Signal). Only caveat I had was I had to tell the computer a cam sync signal and epoxied another hall sensor on my distributor cap and magnet on the rotor.

Then keep the EFI Fast Burn Head. But EFI does have a lot of extra work and learning curve...

 

Yes, I didn't mention it, but know to use an electric pump if I don't knock the hole out; Facet is also my preferred brand.

I've also read opinions both ways on 1 to 2bbl, including a pretty good write up here somewhere that yielded great results, but lets forget that for a while.

Also, no efi planned in foreseeable future, I just need to get this up cheap as possible.

The main question here is which head to use. smaller valves and runners but better swirl & compression with the efi, or lower compression but better runners in the older head? I am going to pull this head off either way to take a look inside.

Now, after this is all over, and I have that tired '85 300 on my stand, long range plans are to rebuild that and I'll look at doing what I need to do - aka not be cheap but also not do something that doesn't make sense. I'll maybe try my hand at a little garage porting, optimum piston & cam choices, and dig up a better intake, but that's not a concern for this used engine.