jagwit

Hi all Simply by using the tin gasket (0.4mm thick I am told) as opposed to the composite gasket (1.2mm compressed I am told) will up the compression on a "high compression" V8 from around 9.4 to around 10.3. Doing so has the additional advantage of not having to use the 20Nm, 90deg, 90deg head torqueing regime but only 90Nm per bolt (as per RAVE - which I think is too little). The benefit is the MUCH reduced stress this puts on the threads in the block which serves to "preserve" the block for future rebuilds. What is so bad about the tin gasket that it should be used?

So noted.

Yep, similar to that but pulled out a Disco1. That Rangie dash is the so-called "soft-dash" that only the very last ones came with.

Has anyone fitted a Disco1 (facelift) dash to a RR Classic? If so, I would like to hear about the major issues you encountered in this process.

Just Google "zddp cam wear" and you will immediately find that oils that are low in ZDDP causes accelerated cam and lifter wear.

No, trouble was that it DID use the IAT, but overcorrected based on the PV=nRT formula. I only picked up in passing that MS1 has this issue (I dont do any MS1 stuff) but a lot of water has passed under the bridge in the mean time and most likely its been sorted by now.

I've heard this being stated many times before but I decided I would rather opt for an engine that takes longer to bed in than compromising the cam/lifters with inferior oil. This is why I went with the Mobil 1 immediately after the 4.6 rebuild. Whilst I can not comment on the bedding in issue, I can state that my engine did not smoke at all and did not use any oil.

Yes, if you dont want to become and EFI boffin, get the full kit from someone who knows his stuff. I'm sure Nige would be able to supply you with MS2 if you ask him nicely.

I've also done a Thor with MS2 and coil packs triggered by an external ignition box with 4 x BIP373's (actually a 4.0 converted to 4.6). I'm running the injectors batch fired. Dont bother with MS1. AFAIK it still does not have user programmable Inlet Air Temp fuel compensation. This will cause havoc with hot starts. MS2 is a beauty ito value for money, or go with MS3 (more $$$) if you want to go semi-sequential. IMHO there is very little incentive to go semi or fully sequential.

Right that's it!! From now on ALL my engines will get an oil pressure gauge which will sit right next to my coolant temp gauge. I took a drive in the D2 with my family on Sunday to a Jaguar Club event. As I came to a stop at the end of the off-ramp, I just happen to notice that the oil light started blinking at me. As soon as I applied a bit of revs it would go out and stay out. This had me worried and I checked the oil level which was good. Got home in this way and connected up my oil/fuel pressure gauge. Sure enough. At 2000 rpm I only got 1.5 bar and it should be 3.4 bar as per manual. At idle the pressure would hardly register on the gauge. Pulled the engine today, and stripped. I was worried that this blond (moi!) did not apply lock-tite to the little screws that hold the oil pump in place. No problem there. Now I'm worried. Just yesterday I was telling Peter (twingduna) "You only have problem when you can't explain the symptom". I was not running out of explanations. Pulled one of the big end bearing caps off. Looks as new! (Thanks no doubt to the Mobil 1 V-Twin fully synthetic oil I was running) Well, I wanted to replace the semi-race cam with a standard cam, so I proceeded to pull the lifters and the cam. Then I saw it.... The rear most cam bearing shell had come out of the block. That is where the oil pressure escaped. BTW, these lifters had now done about 10 000km. They show no trace of having been used. Cam also looks brand new. This re-inforces my view that my choice of oil works well. I have chosen Mobil 1 V-twin (20W50) as this oil has the highest % ZDDP that I can find. Using an oil with inadequate levels of ZDDP will kill your cam and lifters (particularly on the Rover V 8).

I've heard it said so often that 750degC is max EGT a turbodiesel should see. Is this another of those instances that someone's opinion is repeated so often on the internet that it has become defacto "fact" or is there some scientific basis for this figure somewhere? I've installed an EGT into my TD5 that's been tuned up quite a bit. I get 500degC when cruising 120km/h at 2600rpm (Disco 2 transfer case) and 870degC when giving it stick up a hill.

Does anyone know what the resistance vs temperature values should be of the coolant temp sensor for the instruments on a facelift '95 Discovery 1 (v8)? I am running an 82degC thermostat but the instrument gauge reads way too cool. I measure 84degC with my infrared gauge on the thermostat housing and I get 310 Ohm on the instrument coolant sensor.

The Throttle position sensor on my 97 D1 3.9 V8 is not good anymore. Its fine just off idle but with foot off the throttle it is intermittent. Does anyone know where I can get a good quality replacement? Local outlets charge more for it than a MAF for the D2!!

DARN!! You are right on both counts. Dizzies don't feature on my horizon any more which is why I keep forgetting about that little detail.

Hi guys Has anyone tried the 4.6 Cam (ERR5250) in a 3.9? Please share your findings as I am considering doing so. Here's why: I believe the 4.6 cam will deliver more torque and power in the range 2000 - 5000rpm than the standard 3.9 cam which delivers less max torque, but more evenly over a wider rpm range. I have no evidence to think so, this is pure wishful thinking if anything on my part.

Please do measure the depth on the 3.9. You may find that a head bolt turns in easily (please measure this) and then gets to a point where it can turn in further but with more encouragement required from a spanner/socket. I suspect this would be the transition point where used thread meets virgin thread. Please also measure the depth if the virgin thread is also used.

Interesting info forthcoming from ARP: Using standard stretch bolts with 20Nm + 90deg +90deg (as per LR Manual spec) on a test instrument resulted in 14000lbs of force! Using the ARP studs with 80ft-lbs resulted in 14500 lbs of force. This means there is nothing wrong with the 80ft-lbs spec on its own. Matched with appropriate thread depth, there should be no issues with this torque spec.

Thanks Nige Well, that's the thing, the pamphlet that comes with 124-4003 specifies 80lbsft. It just does not seem right. Where do you get the 65-70? Buddy here in SA has 3.9, 4.0 and 4.6 blocks lying around. He will measure later today.

Nige, the problem I found with the 124-4003 kit is 1) that the the course thread end of the studs that screw into the block is too short. The course end only offers 22mm of thread whereas the OEM stretch bolts utilise about 29mm of thread. When you then torque these studs to the 80lbsft as recommended by the kit, the studs tend to pull out from the block. This is less of a problem on a block that is getting head work for the first time but when used on block that's seen multiple head jobs, it becomes more of a problem.; 2) the studs protrude too far out of the block - this has resulted in interference with after market exhaust manifold flanges; 3) the fine end thread is longer than what it needs be - this is not a problem per se, just odd (in fact I wonder if the lengths of thread were not swopped around somewhere between the design dept and the manufacturing plant); 4) the kit includes 5 very short studs as needed for 3.5 heads which one pays for and do not use. Ommitting these from the kit should result in a more cost effective kit. 5) I also question the 80lbsft torque spec - not that I'm qualified to do so, but my experience and gut feel questions this spec big time. Now I have some questions for you: a) how does one specify the "other version" of the kit? b) do you perhaps have a 3.9 block lying around to measure the thread depth on?

To those of you who rebuild Rover V8 engines: ARP has a kit on the market with part no 124-4003 which is WRONG for the modern Rover V8 engines. With input from me, ARP is in the process of developing a new kit specifically for the Rover 3.9, 4.0 and 4.6 engines. One question that has arisen is whether the thread depth on the 3.9 is the same as on the 4.0 and 4.6. My guess is yes, but I would appreciate it if someone with a 3.9 block lying around could use a head bolt to measure how deep the bolt screws into the block and report back please.

So am I, considering its not my car...

"How does it drive?" Very, very strong. I change gears at 1200rpm! Its the old story. Engine is now nice and powerful (considering we live and drive at 1500m AMSL = 0.85 bar) so now the old 4-sp gearbox is begging for a 5th. Those 0.01Ohm resistors are to effect a current limit action in the unlikely event of the IGBTs being switched on too long, to protect both coil and IGBT.

Hi All I converted a Thor 4.6 (as found in P38 Range Rover) to high compression (with ported heads) and installed it into a friend's '81 Range Rover. No major issues but the following presented a few challenges: 1) Heater hoses (Jaguar hoses I had lying in the garage offered a solution); 2) Coolant return from inlet manifold to header tank required an additional connection to the header tank; 3) clean air supply ; 4) fuel supply: An external, adjustable fuel pressure regulator is used with a fuel return back to the tank. I installed a submerged fuel pump into the tank - same as what is used in Disco 1 V8 (95 onwards) - but had to use the fuel level sensor connections (already not functioning) to get power into the tank. 5) Fan cowling - Modified a Disco1 cowl. Still, even without a cowl, no overheating is experienced although temp is not as stable as what it is with a proper cowl. Using an external 82degC thermostat (Freelander) and water hoses as per Disco2. I'm using the original Crank Position Sensor, original coil pack and idle valve but engine management is under control of Megasquirt 2, modified for wasted spark to control the coils directly via a forward ignition module I built to keep EMI noise away from MS. An air flow sensor is not needed in this implementation but a real time barometric sensor is imperative to cater for altitude changes. Knock sensors are not being used.

Good news chaps!!! I've got two, not one, TWO, responses directly from ARP!! They confirmed that the 124-4003 kit is not intended for modern Rover V8s (although I'm still uncomfortable with the 80ftlbs torque for the 3.5). One chap volunteered to see if they can find an interim solution from existing studs, whilst the other would initiate the proper R&D route and will get a 4.6 to this effect. Of course this will take some time. I'm just very pleased (and grateful) that ARP is willing to look at the situation!! I really did not want to go back to those awful stretch bolts on the Rover V8s.

Now if we just find out WHICH spring and HOW DEEP its into the box...