I'm in the process of building a 331. Block from 92gt. Eagle 331 crank. 289 rods. 383 rods. Using that setup comes to. 001 in the hole and with e7 heads comes out to 10.7-1 compression. But thinking of using an older set of 69 302 heads that were ported screw in rocker studs. E303 cam ported upper & lower truck intake. Bigger tb 80mm mass air meter matching 24lb inj long tube heāders. Mustang type auto tranny computer and wiring harness that has all emissions. Stuff removed. The reason for this setup is I have all parts laying around. Going into 85 f150 4x4. Am I way off or right on

 

Oh. Some things that don't really matter but noting. 4bolt main cap conversion. Electric water pump. Dual remote oil filter adapter with 2 2qt oil filters. High volumn oil pump roller tip 1.6 rockers

 

Sry 383 dome pistons...darn cell phone

 

As long as the truck has lots(4.10 min) gearing it'll run well but the heads are still gonna be pretty restrictive.

 

I figured heads were a holdback. If I can come up with a grand I will get aftermarket heads. And yes 4.10 gears and dana 60 rear and figure out a way to convert to 8 lug with the fron. I'm running 32x10.5x15 and enough room for 33's

 

I'm thinking the 69 302 heads might work depending on how they were ported but they might put the CR up there. Given a magic lamp which heads would you use and would you use the B303 cam or something a little more torque based?
Edit: E303- my bad.

 

I don't like the alphabet cams at all but your compression is a bit high for a torque biased truck motor and that E cam will help bleed some of that off at low rpms... down side being the motor won't have the grunt you're thinking it should. If I were doing it I'd start looking for some used aftermarket set with bigger chambers to bring compression down to the mid 9's and then use a cam with 15-20deg less duration to bring the powerband back down to something more streetable like 1500-5500rpm.

 

Thanks Conanski- I had a feeling you were thinking that and I agree. I said magic lamp- you'd still get used heads? Never mind- you probably would. LOL.

 

Used heads on a budget yes.. if you got $1200 or so burning a hole in your pocket then by all means get a new set.

 

I was really trying to get you to be more specific about what you think the ideal heads would be for this motor- valve size , runner cc, combustion cc....
As we already covered- CR can be an issue and it can get worse with aftermarket heads. So put your thinking cap on and let the OP know what to look for.
Sorry to put you on the spot- but I know you are up to it!

 

To be honest- these are the one thing I wish you didn't have. I would rather see flat topped or better still- dished. The reason Conanski is recommending aftermarket heads is that they breathe better. I don't always agree that is a good thing. To break it down in it's simplest form- an engine is an air pump- the more air it can move the more hp it can make.

But in reality- every thing has to be in balance. You have the low gears in the rear end to help with a bigger breathing engine but what about the trans? If it's an automatic you'll need a higher stall converter or it will be a snail from a dead start.

But back to the motor and what I was thinking- I really haven't even thought about building motors in years so some of what I remember may be off.I don't like the alphabet cams either and I have no idea what the exact specs are for an E303 but if Conanski says he would look for something in the 1500-?? 3500?? range (to me the first# is the one that counts) tells me that cam is about what I thought it was.I don't know if Conanski dislikes them for the same reason but unless I'm mistaken those cams are not dual pattern and I believe small block fords do better with them because of the shortcomings of exhaust flow in the heads.

So- back to pistons , heads, breathing, and CR. In my opinion- I would rather see a lower CR with dished pistons and the old ported heads. That way if you felt you needed better breathing heads- aftermarket heads wouldn't put the CR In the "forget pump gas" range.

One last thought- you can live with a motor that isn't quite as fast as you would like- but one that tears itself apart from preignition is no fun at all.

 

you are right its a big airpump. Aluminum heads will always outflow and dissipate heat better and you can get them in the same head cc as iron heads yes you can port n polish them but to get them to all flow the same and even compare to aluminum the price would end up more then alum. sure you could use 351c heads that might outflow the smaller aluminum heads but then you are limited to intakes. I want to stick with hyd roller lifters 90% of those cams are drag raced based not for bottom end plus I already have the e303 cam, sure I guess I could get a custom ground cam.

 

oh, sry bout the missing periods and commas, I tend to forget them right now its a stock 4spd tranny, in next 2yrs I want the nv4500 I graduated in 2000 with an associates degree in GM. One of the classes was that tranny and as far as im concerned that is one of the most bullit proof trannies available plus the granny gear and overdrive and pto on each side. Anyways, with 4bolt main conversion, for some added strength. remote oil dual oil filter and both filters being 2qt and if need be oil cooler plus aluminum heads electric waterpump and a good aluminum 3core 1" cores and a good tune under 11-1 compression on 89oct should b good

 

OHHHH YEAH- A 4 speed changes things a WHOLE BUNCH. You can get away with a much less "torquey " motor that way because you can dump the clutch just this side of catastrophe and what it lacks in torque, it's going to make up for in HP!

So with that in mind-you can get away with an engine better suited to a lightweight hotrod but it still may not be your best course of action.

To me- heads/Cr/ and cam are almost everything. The better you match them the happier you will be. Knowing what I do now-I would say use the 69 heads for now. (Easiest thing to change and might work well with the rest of the motor. CR will be crazy high -but been there, done that- and it's better to find out for free (so to speak) how this motor performs with high compression before spending money on aftermarket heads.
JMH...Dum A♣♣ O.

 

Yea, im gona use those heads for now, buy when get the chance a. luminum ones eill b purchased not it mattrts a whole lot but A9L computer with a chip and msd 6al box all sealed in a weatherproof box will handle thr spark