Ive been reading thru old posts but kinda ended up with more questions than answers. lol

My nephew & I are each building OBS F250s from ground up, in in case it makes a difference in engine build parameters they will have NP435 tranny, NP205 TC, 4.56 gears & 36x10-16 tires.

We are on Big Island and max speed here is 55mph and even that is only for a few miles at a stretch, so low end is where it's at for us.

Rebuilding the engines, using carb heads polished up.

Was looking at Clifford's twin carb & manifold system, it's a bit spendy but if that's the better way to go then so be it.

But are there other options that will work as well that are less expensive and/or simpler?

They claim with rebuilt engine and their twin carb intake system has flat torque curve & puts out 325 hp & 400 ft lbs, is that realistic? We don't have any set power output that we're needing, just as much as reasonably can get.

Questions,

If using Clifford single carb manifold and a Weber or other carb, what kind of power can we get with low end and flat torque curve?

If we use Clifford twin carb manifold and not Weber carbs, would that work well and be less expensive?
Not trying to be cheap, we want to build them right, but if there are other options that are less expensive, simpler & less maintenance etc then pursue that option.

Cheers, Allen

 

Good news / bad news.
First the bad: I think the Clifford performance numbers they quote are insanely wildly optimistic.

Now the good news: I think their dual quad intake withtwo 2V carbs works great on the strip and on the street. I've got one of both.

Even better news: The Autolite carbs work great. Plus they are cheap and easy to build.

If even that is too rich for your blood get a lower EFi intake and fab the top as you like it.

 

Clifford's #'s have always been over inflated. So take their claims with a grain of salt. It would take some pretty serious head work or forced induction to hit those #'s ( especially the torque ) . People get too hung up on the #'s. The #'s your engine makes will depend on your engine. Swapping the intake and carb/s isn't going to give you 100+ hp increase.


My personal favorite intake/carb set up is the Clifford Dual carb intake with a pair of Autolite 2100/Motorcraft 2150 2V carbs. Those carbs are simple, reliable and perform good.

But a Clifford single carb intake or Offenhauser C-series intake perform good too.

I like the Autolite 2100 2V or the 4100 4V carbs. But these are carbs that were built in the 60's. So they will need to be rebuilt or bought rebuilt. You aren't going to be able to buy these new.

But really you can get just about any carb, within reason, to perform well on these engines with some trial and error/tuning.

 

Thanks guys, I kinda figured the power output was a bit 'optimistic' but would like whatever can realistically obtainable. :-)

I just looked on their website and they don't list the twin carb manifold only for sale, just the single carb version.

What do you think of his engine rebuild kit?
Ford 240/300 $899.00
6=8 Rebuild Kit: $899.00
Aluminum Alloy Pistons .030 or .060
Chrome Rings .030 or .060
Main .010 .020, Rod Bearings .010 .020
Cam Bearings STD.
6=8 264 Hydraulic Camshaft
Hydraulic Lifters
High Lift Springs
Chrome Molly Retainers
HD Valve Locks
Chrome Molly Pushrods


Mods to make:

Cross Hatch for Chrome Rings
-0- deck the Block
Check Valve Stem Length. Polish tops.

Use 3/8" Screw in Studs/Guide Plates
Mill .060 & Blend the Runners.


Larry wants $1100 for a head,without core, $950 with core, (but since we're on Big Island it would cast as much to send him a core head as would get for core), with this done to it:

Check Valve Stem Length. Polish tops.

Use 3/8" Screw in Studs/Guide Plates
Mill .060 & Blend the Runners.


If that's a fair price then fine but I don't know what a good rebuild kit and head rebuilt costs.


Want to use the best parts to build them, especially the internals. Bolt on stuff isn't quite so bad since they can be swapped around and experimented with.

What would you recommend as a rebuild kit, or selection of components, I don't mean it has to come as an all inclusive kit, parts to rebuild it right. Top of the line but not custom parts. Use ARP screw in studs & guide plates & ARP bolts and studs where ever appropriate. Roller rockers?

What would you do to the head and what parts would go in it?

Cheers, Allen

 

It's not listed on their website anymore. Contact them directly for the dual carb intake. Last time I checked I believe it was right around $500.00 with the two carb mounting adapters.

I would not buy anything but intakes or headers from clifford's.

And I would also stay away from their cams. They had some issues with them. You are better off getting a cam from Comp Cams, Isky or Crower. I'm going with Crower valvetrain parts on my current projects.

I don't use rebuild kits. I prefer to buy the parts separately. And I like to get my parts from Summit Racing or Jeg's.

 

OK will do, thanks. I'm going to start a help design my engine build tomorrow and try and distill down which specific components to use and exactly what all to have done on the head.

Cheers, Allen

 

I'd start with a set of these.I think with my racer's discount they were about $150 with pins and a ring set.

 

Thanks FTF, I shall use those pistons.

If I understand the procedure correctly, I take my block & crank to the machine shop and let them measure the bore and crank to know what size they will be bored & turned to. Then order the pistons and/or kit for appropriate size pistons & bearings?

Summit has two Sealed Power kits that that have pistons, rings, bearings, gaskets etc. Sealed Power part # MKP6343A-000 & # MKP6188A-000, I couldn't tell what the difference is.

Should I use a kit for this part? Not one with the came but just the piston, rings, bearings, gaskets etc.

Cheers, Allen

 

Yes, work with your shop to figure things out. If they won't - don't.

Start with the piston kit. You can decide on the cam later after shopping for what you want/need/ can afford.

 

The piston kit is the one with pistons, bearings, gaskets ect, correct?

As you say will get cam, lifters, rockers etc after get the block sorted out.

Cheers, Allen

 

Nope - just pistons, pins and rings

 

OK thanks. I'll check Summit.

Greg, I really appreciate your kindness & willing to help. :-)

Cheers, Allen