Early alloyhead, rear seal, cams?

[Anonymous]

Im looking for an early C1, 2 or 3 carby Head. I Heard from xtaxi in previous posts that some of these had rear seals that leaked badly. Is there a good rear seal for these that should not leak (maybe like the neoprene 302 one i have to mod slightly to fit my 250 2V or other?)

Also what do I do about the dip stick that needs to be at rear for fitment to a TD Cortina? Would it be better to get a Iron head engine from a TE Cortina so that the dip stick will be in the correct possition and then put an early alloy head on it ? I realise Ill need to mod the air box on the fire wall for an alloy head inlet manifold to fit.

Also heard from previous post that some of the early alloy crossflows had cams that wore out before the first service. Why is this? and what is the way to ensure this does not happen
Dynoed 250. Did you get a chance to check your 240 at 50 cam with the gentle ramps for signs of wear?
Sorry for all the questions I just want make sure of all this before I go ahead.
Cheers Tim

 

[xctasy]

MAIN SEALS:
Early x-flows should be the same as tall deck 200 and 250's, from 1971 to 1983. Then they changed to the 360 degree seal, then, about 87, to the dog turd. If its the early 76DA or pre 84DA block is should be easy to retofit the Neoprene 302 seal into the rope seal block.

Ref http://www.mustangandfords.com/techarticles/5226/


The sharp ridge of all rope seal cranks can be removed. Or just use the later 84DA crank. All 250 Falcon cranks have either a casting code or it's got an MA code, but I can't remember which.

The flange and back part of all Aussie sixes from 71 to 93 are basically Windsor and Cleveland V8 spec, so if you modify it to suit the later 302 Windsor seal, then you'll have no problem.

DIPSTICKS
The dip stick was bossed on all post 76 engines, then got lost on later engines. You may have to drill it out the cast iron boss, and whip in a Cortina dip stick.

Hint. If someone is behaving like a drongo on this forum, call them a 6750. (Ford code for a dipstick.)

early C1, 2 or 3

I'm no expert here. I haven't had a complement of the early heads. All mine are HF5 or 6's, or early iron x-flows, no XD 1/2 heads.

FAILURE OF CAMS, LIFTERS, PISTONS AND CAM DRIVES

Looks to be a problem on the lean burn XF engines, not any of the XE Alloy Head II or XD 1/2 Alloy Head's. This is line with what ex Ford Special Vehicles, ex Repco front man Bill Santuccione said in an early article in Street MACHINE, 1990. Avoid the later kidney shaped lean burn heads if you are modifying the engine. All the cam, lifter and drive issues may have been detonation related. (my inferance).

The other point is pistons were low drag in the later XF 4.1's, and never liked a big rev past 4500 rpm. Early iron 250 x-flows reved way over 5000 rpm with ease.


ALLOY CONVERSION TO CAST IRON X-FLOW BLOCKS

The last point is that the water galleries on the block are basically the same, and all you need is to broach out the x-flow cast iron blocks to suit the two anti fretting location roll pins.

I'd use whatever pre 84DA, post 76DA block. The 78DA block on my XD looks like its got everything there to make a tuff base for a great engine.

 

[Anonymous]

Thanks Again, your always a help. Ive got a neaprene seal for a 302. I spoke with a mate who says again that on the speed way they most often use the iron head crossflow so Im thinking I may use one of these out of a TE just for ease and simplicity and as Im only after staightline performance.

Im not certain but think there may also be a little more wall thickness to port around the valve bowls and the exit from the runners for fitting of bigger valves (the runners probably are big enough) (ie often see ported Iron head crossflows for sale)

Only reservation is that the potentual power output of a alloy crossflow is well documented in this forum where as the iron crossflow has almost nothing recorded about it. I dont like dealing in uncertainties when dollars are involved?Anyway from what you say it is not that difficult to put an alloy head on latter if it fails expectations (with engine in?).

Another one of your posts for me to print for quick referance thanks Tim.

 

[xctasy]

To me, the TE engine has all you would need to straightline go. It's simply the heaviest six cylinder 250 around, with big 35 to 40mm ports and lots of room to do bigger valves. The lack of inserts is fine for racing engines, as the Alloy head ones are hard to shape. The cast iron head also dosn't burn up under detonation like alloy heads can. The alloy heads are repairable , though. Iron ones are not as easy to fix.

The stock intake manifolds suck because of the non symetricall ports. But its cheaper than restuding an alloy head that has pulled its rocker stud out.

It's smoother than the alloy head by a great margin.

Find something YOU like. With any Ford six, even an XF or log, you can't go wrong if you've done your homework.