I have a 390 V8 in my 1975 2wd F250. I will be using a cab-over camper quite a bit and even towing a Jeep with this truck.

That said, what modifications would YOU recommend making to the engine for more power without losing reliability? It already had a 4-barrel holley on it and it seems to work well.

I know about checking the condition of the engine and such. I am not asking about that. I am asking about performance mods.

Also, if you have any great parts sources post those too. Websites and companies w/ phone numbers.

Sorry if this is a repeat, but thanks in advance!

 

Let's see if I can get this right.

Edelbrock Performer RPM intake - Some reccomend the Performer for low end torque.

600 CFM 4V carb

Pertronix or other hot ignition setup. Good coil, big wires etc.

Headers if you can spend the money to get good ones. Cheap ones may be more trouble than they are worth.

Dual exhaust- 2.5" plumbing

And the FTE FE favorite Crane 343901 cam.

Let's see what the rest of the crew has to say!

 

First off the crane 343901 cam would be a great cam for the low and midrange. If you want to change manifolds I would get the performer RPM. Headers will help a lot. I would recommend the flowtech headers if you are looking for the cheapo painted type. There are better headers out there if you want to spend the money. The carb should be no bigger than 650cfm for this setup. Any bigger is going to hurt the bottom end a little. How much dinero are you willing to dump into this beast? I would recommend summitracing for the parts.

 

How much does this cam cost?
Im interested in one myself

 

For the cam kit the part number is CRN-343902 at summit.. Just go there and type that part number in the box and do a search. www.summitracing.com

 

Thanks a ton

 

Firstly, Welcome to FTE! Repeat posts are not an issue. We enjoy going over this stuff all the time. Measure your stroke. Many discover a 360 where they thought a 390 resided. Take out number one plug, disconnect the coil, turn the engine over with a piece of wire resting on top of the piston and a sharpie felt marker resting aganst the wire. After a couple of revolutions measure the length of the mark. 3.5 inches is a 360, 3 7/8ths inch is a 390. Warming up one of these engines does not have to cost cubic bucks! You just need to be careful and take it one step at a time. I like Edelbrock 600 CFM carburetors, performer intake, with hydraulic lifters on a crane 901. Excellent results in the ignition department can be achieved using Pertrinix Ignitor and coil. Ford flat cap, long nose rotor and 8mm wires. I prefer 2 1/4 inch exhaust pipes and stock manifolds for lower RPM pulling trucks. Like the one you are describing. I am happy to see that most of us agree on the basics. This engine/exhaust is what I have now and I am very happy with it. Fresh 390 going in soon!
William in Atlanta

 

I have to agree with the posts also. I like the Mallory Elec. Ign. it is a simple drop in replacment. Ed carb, Ed Perfomer Intake ...both good stuff. My old Morroso headers are finally giving out. Go for good headers, nothing but trouble with cheap ones. I've been reviewing the FPA and Stanley that I saw recommended on another thread. Both of these are 1/4" - 3/8" up top and use up-to-date 'doughnut' style gasket at collector end.

Enjoy!

 

Since you asked about that particular Crane cam, I picked one up from Summit this week for $169.95 with lifters. The associated spring set for this cam is Summit part number CRN-13309-1 (Crane 13309-1), $99.95.

 

Are you going to pull the engine out of that beast or just do a bunch of bolt on stuff?? If you pull the engine and have it machined then you will need to do the oiling mods. (do a search in this forum for oiling modifications). Also something that isn't stated in the oil mods is restricting oil to the heads. The heads are typically over oiled. Even if you don't pull and machine the engine you can still restrict oil to the heads. Use a .090 holley jet and place it in the hole for the oil passages leading to the rocker shafts. This will allow for more than enough oil to the heads and help keep oil in the passage for the mains and rods. On a mild performance such as this it is not "A MUST DO", but it is recommended.

I agree with most everything that was listed above. I would use a Performer RPM intake, 600cfm Ed carb, and the cam listed. I say RPM intake becuase it doesn't hurt performance and it gives you a better base for later upgrades than the Performer 390. Thats my input.


Scotty

 

has anyone used the Crane 343941.....??? 216/228@.050"

I might try that with a single plane streetmaster intake....600cfm edelbrock carb.....

I guess it's not a highly reccomended combo but I like to experiment....I've never built a FE before but I found it difficult to get a even fuel distribution when using dual plane intakes on cleveland motors...The performer rpm looks great but they cost a lot...I haven't been able to find any deals on one...


I'm also building a C6 with a transgo shift kit and a TCI staurday night special converter....

 

I have seen the Pertronix listed a couple times in this thread. If his is a 75, it should have the Duraspark electronic ignition. Save $70 for the Pertronics, you have the good stuff already.

 

My 390 is setup like so:

Redid the motor 10 years ago.

Wolverine cam 292/292 adv, 230/230 @.050, .554/.554 lift. Degreed in by my machinist for low-end torque, not sure anymore of how far advanced. Heads had all new seats and valves, with 428CJ/SCJ exhaust-sized valves (stainless). Double-valve springs, whatever Wolverine suggested for that cam. TRW forged pistons, flat-top. 10.5:1 compression (or more, heads/block milled/decked), needs 93 octane.

Edelbrock performer 390, Holley 750 (yeah, I know...), stock '76 electronic distributor w/MSD 6AT. Blackjack headers to 2.25" true-dual w/FOUR low-restriction mufflers. Flex-fan replaced four-blade anchor.

This thing pulls incredibly in a 5500+ lb 4x4 '74 F250 in 2nd gear (435NP) w/4.10 and 33x12.5R16.5

All the way from 1000RPM and up. It's hard to get moving without spinning the rear tires even feathering the throttle and clutch.

The Holley 750 could still use a bigger accelerator pump shooter (already at .040), but it spins the tires easily.

No pinging, even with 4000lbs in the bed. Although, I had to setup the distributor with an adjustable vacuum advance. Hooked the vacuum advance to the timing port on the Holley which provides vacuum at idle. Advanced the idle timing up to around 22degrees to keep the vacuum around 12in at idle. Doesn't lope TOO much. Vacuum port on Holley actually RETARDS the timing when you hit the gas to keep it from pinging. Plenty of low-end torque and enough power at 5000RPM to scare you. Full advance is around 34 degrees.

art k.

 

I'm using one in my 390 build now. I'll let everyone know how it goes when I'm done.

 

Want something different? Dump a 428 crank in it and make a 410. It'll have to be rebalanced, of course, but you should do that anyway. (if it's a rebuild)
Scotty's right about the heads over-oiling. Also, some aftermarket rockers are cross-drilled and they spray oil all over the place. Positive stem seals, at least on the intakes, are a good idea.