The V8 Owners Forum -

Badger,The mod to the inlet manifold sounds interesting, and would save some effort at the front end. Also the GEMS fuel rail has been mentioned earlier so its definitely worth a look and trial fit. I think in the absence of any recommendations to the contrary, I'll stick with the 3.9 EFI cam as a r...

Dave,
is there a rule of thumb for what skim depth relates to a corresponding rise in CR?

Dave, you've got me thinking about compression ratios, just check this logic for me will you? Original and present CR is 9.25:1 with tin gasket and 36cc heads. When I put on the later heads, with a composite gasket, the composite gasket will make up for the reduced head volume (more or less accordin...

Thanks for the info, I'll have to trawl through the RAVE manual to see what the 4.0 and 4.6 thor fueling set ups are with regard to the pressure, I know there's definitely not a return line on the Range Rover. As for the heads, I don't know what the amount will be taken off to get them flat - minima...

Hi Dave, from memory I think its either 9.25 or 9.35:1, can't be sure without getting out the gunk and having a clean up first! I figure I may loose a bit with the composite head gaskets but may gain a bit with the new heads? That's maths and never my strong point. I'm quite looking forward to it as...

Chris, Oh yes the rocker covers - guaranteed to start leaking about 6 months after the build and, as you know, can't get to the inner two bolts to give em a tweak. I had a problem with condensation that I traced to the LH ( as you look at the front of the engine) R/Cover , the plastic shuttle in the...

Dave, Eliot - thanks for your replies; I don't know about the top end performance of the thor, but if you give it enough on the go pedal it moves the Range Rover on pretty smartly, personally I've always found the SU's run out of steam at the top end so anything extra will be a bonus, when you think...

Dave, I had bought a spare setup for a LPG conversion on the 4.6 Range Rover we have so it seemed logical to just use that as it looks a better set up all round over the GEMS. Now you mention it, it'll sit lower than the GEMS plenum as well. It also gives you the opportunity to get over Kickdown cab...

Hi All, I'm nearly finished locating the donor parts to fit a Thor injection system on my 3.5 P6. After much thought the mega squirt v3 looks the best option to drive it. Has anyone on here done the conversion ( whether in a P6 or not)? I had thought about just putting a 4.0 lump in it but the engin...

Thanks all, please keep your opinions coming, I've stripped the heads and the offending drivers side is showing some signs of wear, so a skim is definitley in order. The gasket was almost burnt through at 6 and leaking between 2 &4! Nice tell tale bluing of the exhaust manifold gasket at 6 which...

Got HIF6's on my P6, to set them I remove the bottom of the carb (4 bolts) and with it perfectly upright and inverted check the float level with a straight edge, through the bottom of the curve of the float and body casting side to side, can't remeber the gap but there should be one listed, the fuel...

Hi all, thanks for the replies. This question came up as I've just taken a head of a car and theres definite signs of leakage to the point where the gasket has nearly failed by No6 and is letting by between 2 and 4. The ARP studs were nipped into the block but obviously somethings amiss. So I guess ...

Hi All, as a follow on to my post about head sizes and thicknesses when replacing on older block, could I ask for information on the need to torque and re-torque head gaskets? I've seen a post on the Mini forum that talks about cycling the ARP fasteners 5 times before final torque is applied, but my...

Thanks all,
great diagram - makes it all clear now. I'll have the valve seats recut and stems checked, then its the long haul to FI the engine. I see theres various posts for porting the heads, will probably only match these as I hear there's not much body to playwith!
Thanks again.

All, many thanks for your replies. I managed to get hold of a set of heads off an early - to mid P38, so I'll attempt the check as per Denis's figures. Denis would you be kind enough to just give me a better location on the head to take these measurements from? Thanks again - just didn't want to end...