Compression info

Hey all just fishing for info for the van
i have canned the 4.0l into transit idea and decided to put an alloy head and an efi manifold upon the old iron head block

I have a HF-5 E2 head that came off an 87 unleaded XF now want to do is bolt it on my existing 76da block run straight LPG and an sc14 supercharger will the head bolt straight on or is there some isues with the water galleries

doz anyone know what kind of compression i will get by just bolting the E2 head on? im hunting for around 10 to 1 if the head swap wont achieve this how much do i need to remove from the head or what 250 has the smallest dish pistons?

What kind of cam are you going to run? An LPG one? Is the motor bored out?

I think the only snag to fitting is, there are supposed to be a couple of dowel sleeves like an eight has; these locate the head/gasket. A drill or mill bit with pilot could take care of this part. Not as hard as the blue head/red block install.

49.6 ccs verses 53 cc or thereabouts. The XC was 9.0, the EFI XF was 8.8. Difference was the 22 verses 27.9 cc piston to make up the difference.

The compression calculator will tell you the difference on a XC. It goes up 4 points to 9.4:1

http://falconperformance.sundog.net/compcalculator.asp

76 to 79 XC's were all blueprinted at 9.0:1. The poduction varinace means that any given year of Ford X-flow could have had any level of compression.

With 53 cc chambers, the gasket is 41 thou, the deck register is 16 thou, the std dished piston was around about 22 cc, (but was 27.9 cc on the ULP XF's). The variance was both the chamber machining and the pistons.

i've done this a couple of times now and have never worried about the dowels. the iron head doesn't have any and it's not a problem.

just make sure you use an alloy head gasket and the head bolts from the alloy head. take two of the old iron head bolts, cut the tops off and slot them. Use them to align everything before bolting it up.