Thread: V8 Engine Identification

Originally Posted by 748Rum

Yep, have heard some interesting stories with the transplant. Figured I would go “mild” in the first iteration and then can always increase the power from there. Somewhere between 220-240bhp would be good as a starting point.

Or pay close attention to the chassis... the torque twist at 4500rpm when changing fron 2nd to 3rd was brutality defined

From your pics one can't say if it is a cross-bolted block or not. See the bolts at the bottom of my P38A 4.6 engine:

4.6 right side.jpg

Re compression ratio, is it stamped on the engine where the engine number and dipstick hole is, e.g., this pic of my P38A engine. CR 8.36:1

4.6 engine no.jpg

Originally Posted by Slunnie

To add a bit more, I understand there is some inconsistency in the manufacture of the sleeves and the 4.6 had the better manufactured (same spec though) sleeves put in them.

When the blocks were made and tested with those that passed further graded - the lowest grade were designated a 4.0 block, the highest grade blocks were designated 4.6 and those in the middle could become either 4.0 or 4.6. There was a paint code that was used - where a slash of paint was put on the bloc.

From another forum so not sure if it is true but I think it is:

"The thickest walled blocks were designated "red" blocks and given a red paint dab on the outer cylinder at the valley, I believe it was number 3. "Reds" we're always used for 4.6 engines. The next best blocks were "yellows", if they ran out of "reds", "yellows" we're used on 4.6. The worst blocks were "blue" and used for 4.0 motors.

There are paint dabs all over these blocks but this dab was always on an outer cylinder in the valley. I actually tore down a 2001 4.6 that I could clearly see the red dab on. "

Anthony - when you strip your engine - just check the crank to see if at some stage a 4.6 has gone into it. It will have 4.6 stamped on it. Also check for top hats - the liner at the top will be wider (thicker) than it is at the bottom when looked at from the crank area - not sure of thicknesses but a normal liner is about 1 - 1.5mm thick, as is a top hat liner except for the top hat at the top that is much wider about 2-3mm. You can see the width of the top hat in the second pic - you can also see why the engine had been scrapped but is all fixed now.

P2070262.jpgP5050052.jpg

According to Des Hammell (How to Power Tune Rover V8 Engines for Road and Track) in 93 the factory was aware of block wall thickness problems and commenced ultra sonic testing by hand of all blocks and in that year the core and block mould were altered to reduce the amount of core shift possible so that the block wall thickness would be more uniform. After 1997 the blocks were all machine tested with ultrasonic means and the coloured paint system was then used.

Cheers

If you end up with a top hatted block I suggest you use Cometic MLS head gaskets. They come in 94mm bore size so that they clamp the liners more tightly than the stock 96mm I.D. gaskets. A friend of mine had a top hatted motor that killed a few composite head gaskets before I fitted the Cometics.

Liners should be set into a machined step at the bottom. Cant see how they can move - be wary of internet rumours.
Blocks do crack behind the liner near the head bolts - between 3 and 5 or 4 and 6. You must get the block pressure tested before rebuild to save wasting money.

This is an image from Number 8 on a 4.6 59D engine from a year 2000 P38. You can clearly see the step.

Never saw any dab of paint on my engine when I took it out - looked very carefully - so not sure how accurate the info in those books is.

14CUX uses info from the vehicle speed sensor in its calculation, but will run the engine without.
Better to buy an after market job such as FAST Ezi from USA - very simple and uses GM sensors and wide band oxygen sensor. You can program your life away on it. - you can TIG weld a GM throttle body onto the Rover plenum and use GM TPS etc with this system. I did one but sold the car - it has beeb crashed so may be buying it all back if you are interested.
Tps and idle air control are expensive and unreliable in the 14 CUX system - however you can reprogram 14CUX - via burning a new chip - and looms, parts and ECM,s are at throwaway prices everywhere.

If you want more info PM on the programming of 14CUX PM me.

Originally Posted by peter51

Liners should be set into a machined step at the bottom. Cant see how they can move - be wary of internet rumours.

Here's a photo I took of such an internet rumour!

DSCN5737.jpg

Have you got a picture of the step at the bottom of the block?


It must have broken through the machined step. If you have it please display it - can piston friction brake the the step way?