Greetings Gear heads ! I need advise on what parts are best for using in a 351-W circle track race engine ? The rules allow, stock rods and crank, 10 to 1 comprssion with 4 valve relief flat top pistons, stock heads without screw in studs,no porting ect, cast iron 2 or 4 barrel intake manifold, 500cfm 2 barrel holley carb, 480 lift hyd cam rule and must run cast iron exhaust manfolds. I am currently running a 1971 460 which is killing the chevys but now need to add 200 lbs of weight due to the horse power advantage I have ,and am told there will be a 358 max cubic inch rule for next year. I need to know which stock heads flow the best,which intake flow's the best and what cast iron exhaust manifolds flow the best. What year blocks are good ect ? I could use info on what trucks or cars these parts come on and part numbers to look for? Thanks for any help !!

 

Stock heads????

Stock Ford heads or just heads that came with the year motor you're using??

Ford N-351's are the best Ford(non-aftermarket) inline head available.....but they are FRPP heads with screw in studs and were never available on a production vehicle.

GT-40 or GT-40P's may be a hot ticket.........in theory a mid '90's 351 lightning motor was this combo (GT-40).....of course with EFI.


Or see if you can use a 351C 2V head.........a poor mans NASCAR combo if you will.


I believe the '69 block has a tad shorter deck heighth than all othe 351's...a little easier to build compression.


Good luck.

 

Thanks for replying ! I have seen the GT-40P heads on ebay and would like to know more about them. What cc are the chambers ? will they work with older cast iron intake and exhaust manifolds ? What type of rocker arms are stock, the stamp steel or cast rail type ? I am also looking at a pair of 1980-93 302 H.O heads, # E6SE any good? Thanks again for the help !!

 

I'd use E7TE's before using the E6SE heads, but I don't know what other folks think. The GT40P heads are good heads, but I'm pretty sure you have to use headers specifically for those heads. I'm also thinking that those were only used on 5.0 explorers so you'll have to drill the head bolt holes to 1/2" to be able to use them on the 351.

 

You'll sure like the weight loss off your front end going from the 460 down to a smaller motor!

Thg GT-40p heads are probably somewhat limiting in the higher RPM ranges. What kind of RPMs do you expect to turn with that motor? Another limiting factor on a 351W for circle track use which really isn't a problem in most cases but is something to consider) is the large (3") main bearings, which create a bit more heat in the bottom end. I'd look at '69-70 351W heads, still fairly easy to find. (check out the Cylinder Head Casting Numbers link)

I kind of like DOHC Marauder's Clevor suggestion (351C heads, I'd use the Aussie heads) but I think the real limiter for you is that cast iron intake and exhaust rule...wow! And I thought my old Late Model rules were tight when I was doing the roundy-pounder thing! But since you have to run a cast iron intake, I think that may be a problem since all the Clevor manifolds I know of are aluminum. I suppose you could use spacer plates and run a 289 4-bbl manifold with a 4-2 adapter for that 4412 Holley, but the ports are pretty small in that manifold, as they are in all stock cast-iron small block Ford manifolds.

Exhaust manifolds are another limiter. There were some pretty good 351W and 289 hi-po manifolds, but they're both hard to find these days. I'll try and dig up some more info on them this evening.

There are a few other things that occur to me as well, I'll ruminate on them during the day and see if I can be a little more coherant (yeah, right!) after work this evening.

But one thing that occured to me...have you considered running a 351C? 4-bolt main blocks are still around, but even the 2-bolt blocks are good and parts are still available, the Aussie heads would be perfect and the intake and exhaust are very free-flowing even on the more common 2-bbl versions. Weight is a bit more than the 351W but still way less than that 460. Something to think about anyway.

 

Thank you for your suggestion's.Cant do the cross breed thing and have thought about the cleavland.My 460 turns 5500 rpm and runs like a sewing machine. Does any one know what a 351-W weighs VS a 351-C ? How much does a 460 weigh? Which would make more power ? The weight is important due to the fact that I am a BIG DOG ! and need to loose weight in the car instead of at the Dunlop. I am the only ford racing in my class and since there is a $450 engine claim rule I dont need to worry about loosing my motor ! And just this week the track is letting the metric stub chevy's take off 200 lbs so they can be more competitive ? But I still need to weigh 3700 lbs?? The class minimum weight is 3500 lbs But like I stated earlyer next season there will be a 358 ci rule, fords get 362 inches. HELP !!

 

The 351W comes in at 525, the Cleveland is only 50 pounds heavier at 575 but the 460 weighs a whopping 720!

I think you could get more power out of a C than a W given the rules restrictions you have.



Why do the Chevys get all the breaks anyway? I sure got sick of it, but on the other hand since I was the only Ford, the tech guys didn't know a thing about them. The stuff I could get away with...

Check this out, from my better days:

https://www.ford-trucks.com/user_gal.../75517.520.390

 

Bet you dollars to donuts the C will have a big weight penalty!!!



Dan, I'm thinking even the 69 351W head cannot compete with either GT-40 head.

The P head has a slightly smaller CC than the regular GT-40 due to the plug boss extending into the chamber. 68 CC vs 70CC(??)

P's are the hot setup in a lot of the stock drag racing classes.......And like mentioned, you'll need Explorer exhaust manifolds.........I have used non-P headers on P's, but not manifolds.


E7's are Mustang GT heads from '87>........better than the E6's.

All the Ford heads on production motors after the late 70's(??) use the pedestal mount rockers......which contrary to popular belief take a little time to lash correctly.

 

You may be right...I was thinking I'd read somewhere that the P heads' flow falls off after about 5000 RPM but after quickly re-reading Shawn Meldrum's page on them, it's more like above .500 lift. I knew there was a 5 in there somewhere...

 

TigerDan, Very cool race car !! I will try to post mine soon ! Thanks for he help ! Keep it coming its a big help !! Are all 351-w cranks the same?

 

I have looked at the ( E6SE heads ) and the ( E7TE heads ), the E6 heads are closed chambered above the spark plug hole and hart shaped arround the valves. The E7 heads are open above the spark plug hole about half as much as a GT40P head and the chamber is straight on the other side of the valves. They both look like they should preform well but which one is better and why ? Is there any other differances in valves or port sizes ? What about the rockers ?

 

Dang, I was hoping you wouldn't ask that!!!

Just from memory, the 86 GT Mustangs were rated @ 200HP with the E6's..

The '87 'Stangs went to 225 with the head swap.........I don't know about any other mods...

Never have heard of anyone actively seeking out the E6's..........sorry if my answers are vague.