390 pistons and cam

[Ranger xlt]

Hi guy's i'm looking into rebuilding a 390. The block is from a 1976 f100. the heads are D2te. What year pistons should i use. Are the older 390's higher compression? I'm not trying to build a Hot Rod just an daily driver and towing a boat now and then. Also what about an RV cam. Any help would be great. Thanks Larry

[Lee]

Hi Larry,

There are many options to use that will answer your request.

Almost every Cam manufacture has an "RV" cam, also there are many piston options.

I can provide you with what I used in my truck when the engine was rebuilt. I aimed to keep the comp ratio at no more than 9.0:1 as my truck is heavy and I also pull a Travel trailer,... also wanted to run on low octane pump gas.

Pistons are Sil-O-lite 1130. Should give about 9.25:1 CR using the .020 steel head gasket or 8.79:1 CR using the .041 composite head gasket.

Not sure who manufactured the cam I have but here are the specs:
Duration degrees @ .050 Int. 206 Ext .221
Valve lift Int. .481 Ext .490
Cam # 643 Grind # ABX

Again, there ar emany options to use.

Take care,
Lee

[Ranger xlt]

Thanks Lee. That's about what i'm looking for. Any other mods worth doing like headers, or intake. I will do the dura spark ign later on. Thanks again Larry I

[Lee]

Hi Larry,

Most agree that the best "bang for the buck" we FE powered truck owners can do is, get rid of those old log exhaust manifolds and replace with a decent set of headers ran through duels.

The factory manifolds did not flow well at all.

Lee

[Busboy]

And get ready for exhaust leaks, starter hassles, clearance issues etc.

[Lee]

Hi,

What Busboy states can be incurred if not mitigated ahead of time.

Sanderson shorty headers mitigate the clearance issues and also the heat soak of the Starter issue.

Also, weld all joints to prevent leaks..... don't depend on muffler clamps.

I have been running a cheap set of Heddman's on my truck for 18 years. Pain in the Arsh to change a starter,.. yes.... but I wrapped the starter in heat protector wrap and have not had a problem in 16 years. Also, welded up the collectors so no leaks there.

For the header to head connection... I use the thick copper exhaust manifold gaskets. Have never had a problem since and they are re-usable. At first I used stock Fel-Pro's and had to replace every few years,.... but no more with the copper.

Lee

[RangerRat]

Recently built a 390 for my 72'. I used cast 360 pistons. Which are affordable and really just 390 flat tops. Compression calculated to 9.7 to 1. I'm not sure what head gaskets he used. Sanderson shorty headers. And a Comp XE262 cam. The valve springs were shimmed for the proper spring pressure for that cam. I'm running an Edelbrock 1406 600 cfm carb. Which out of the box is very lean. I think I went 4 steps richer with the metering rods. And 2 steps quicker for the secondary springs. Wish I'd gotten the manual choke version instead. It's calibrated more for performance and in my opinion Edelbrocks electric chokes aren't all that reliable. And I also recurved the distributor. It has awesome low end torque and midrange. Pulls really strong to 5000 rpm. And with Flowmaster 40 Delta Flows has a very healthy idle.