Thread: Will 3.9 heads fit on a 4.4 (P76) block?

Hi you should be able use what parts you like of the 3.9 on to the P76, I plan to do this also including using later internal oil pump, there's a book out there call Power tuning rover V8's that has a lot of info in it. I have tryed "interim timing cover" fits fine but P76 crank keyway needs to be machined full lenght. I hope to be start moding my engine in few months regards G2

3.5 to 3.9 is a bore change.

I think 3.9 heads should bolt anywhere that 3.5 heads were.

If you top hat liner the P76 block to fit the Disco 3.9 pistons you get a 5 litre...

P76 crank has unique main bearings and has the longest stroke of the RV8 engine family, at 3.5 inches.

Thanks for the replies, I'll pull the heads off the 3.9 and see what damage the moving liners have made. The motor was running fine, shocking noise though. If it's just a matter of a keyway, I might have a look at converting the 4.4 to a serpentine belt setup, have a near new water pump plus a 120A alternator on the 3.9. If this all works okay it might be a good upgrade for my current hack, 1990 rangie, it's getting a bit tired with 320k on the clock and a serpentine setup would be a good improvement. The 4.4 was a sweet motor once I got it all set up.

[QUOTE=bee utey;1610694]If you top hat liner the P76 block to fit the Disco 3.9 pistons you get a 5 litre...

Tempting, but the Disco pistons have done 330,000km vs 115000km on the 4.4, think I'll have to be satisfied with getting the 4.4 going and getting some use out of the good bottom end i've already got. Haven't got a huge budget for this job.

Oh and a reminder, the P76 crank has a different flywheel flange. The manual flywheel is relatively easy to machine to fit, not sure how hard the auto torque converter adaptor would be to modify.

Originally Posted by bee utey

Oh and a reminder, the P76 crank has a different flywheel flange. The manual flywheel is relatively easy to machine to fit, not sure how hard the auto torque converter adaptor would be to modify.

The kit that I used to do the 4.4 conversion included a drive plate adapter for the auto. It was quite a well sorted kit, no longer available I believe. It included an adapter ring for the starter motor, which unfortunately got left on the old starter motor when it died at Alice Springs, will have to get another made.

Another thing to chuck into the ring Holden 179 or 173 pistons fit carnt remember did this a log time ago( a the time buy 2 sets was cheaper that getting rover type) rockers and lifter's holden too.