Modified Stag Rover P38

[V Mad]

I may soon become involved with a highly modified stag project, and I am hoping for some information on the V8 4.5 litre Rover P38 engine.

The car already has BMW rear end, so it is ripe for turning into a 'road burner' and/or track day car, with something lively under the bonnect. I dont want to raise a debate on TV8 vs RV8, just to move on and consider which Rv8 is best for this project.

I have owned two Rv8 powered cars before so I know some of the issues and pitfalls relating to the 3.5 engine, but times have moved on, and the bigger RV8 engines are now coming up as cheap as the old 3.5 ones used to.

As I see it, the main differences which might cause difficulty are the serpentine belt system, and the height of the plenum, which loooks much higher than the earlier ones. I hope that the 3.5 headers made for the Stag would fit the 4.5 but not sure about that. Sump may need changing too.

If anyone can shed some light on these, you comments and thought would be welcome,

[Mister G]

I would think the overall height from sump to the top of the plenum would be the limiting factor, they are tall engines.
Not sure what you mean about the Serp belt as IIRC the alternator sits below the top of the plenum.
John

[V Mad]

Yes I think the height could be an issue. I wonder if the serp belt makes the engine too long? I suppose the rad could be moved forwards if necessary.

[mjheathcote]

Don't you think the Rover V8 has had its day? It doesn't even rev as high as the Triumph V8 for a start!
There are so many more modern V8's to choose from.
If you are going to the trouble of an engine conversion, might as well make it a good one...at least 32 valves for a start!

[KOY 23]

Never heard of a 4.5. P38, do you mean 4.6? Not the most reliable engine, leaky liners.

[Staggard]

Never heard of a 4.5. P38, do you mean 4.6? Not the most reliable engine, leaky liners.

I am behind you 100% this one John, coz if anyone knows about "leaky liners " its you ole son

[mike@thenook]

Maybe need to wash my mouth out for suggesting it but what about a nice BMW 6 unit....? Anyone ever tried?

[Knockwurst]

Wouldn't a TVR 500 engine from a griff or chimaera fit?

[mjheathcote]

Maybe need to wash my mouth out for suggesting it but what about a nice BMW 6 unit....? Anyone ever tried?

Oh p le a s e, a 6?!!

Wouldn't a TVR 500 engine from a griff or chimaera fit?

Its still a Rover, so yes.

[V Mad]

Some good points there, thanks.

Yes I do mean the 4.6 used in the P38 as these are plentiful at the moment (its confusing as there were so many varieties if the same basic design!).

Wouldn't a TVR 500 engine from a griff or chimaera fit?

I think they did use the 4.6 in the TVR, and a 500 would be nice but maybe pricey. Would it fit, well yes but not without some modding I suspect.

Don't you think the Rover V8 has had its day? It doesn't even rev as high as the Triumph V8 for a start!
There are so many more modern V8's to choose from.
If you are going to the trouble of an engine conversion, might as well make it a good one...at least 32 valves for a start!

I dont really want a modern engine, the RV8 is a period modification, and was nearly the one the Stag would have had. Its relatively cheap, well understood, lots of support, and if its good enough for the Morgan and TVR, its good enough for the Stag. The 4.6 has up to 300 ftlb at only 2600, which will make it so driveable.

I do have a hankering for putting a Ford Windsor v8, such as a 302 (5 litre) which is a very strong engine, but for that or any engine other than the RV8 I would have to have a custom set of headers made, which could prove expensive, and tricky. RV8 headers can be bought used or new off the shelf. The Windsor is the same weight as the Stag engine which is good, and quite compact so it could be a good fit. So I havent ruled out the Windsor engine yet, especially in the 300 BHP crate engine form at $2699 from Summit racing

A nice BMW 6, well as it happens I have one of those in my old BMWs (528 etc) and they are sooo nice, but for the Stag it has to be a V8.

[KOY 23]

I am behind you 100% this one John, coz if anyone knows about "leaky liners " its you ole son

That's the last time I share any personal details with you. I will be 100% behind you in Spa, sweet dreams!

[Staggard]

That's the last time I share any personal details with you. I will be 100% behind you in Spa, sweet dreams!

Wow that's two of you now, and there was me thinking that my pulling days were over

[jagorstag]

Hi Chris,

Sounds like a fun project! How about a GM 350 crate engine, if I remember correctly you could have a 300 bhp version together with a brand new Tremec 5-speed manual gearbox for about 4500 GBP or so from a UK supplier?

Then again, if you're considering a BMW 6 then perhaps the "big 6" M34 or M35 would be preferable, much stronger than the "small 6" from the 528 and similar, i.e. it'd be less likely to warp its cylinder head when overheating...

Cheers,
Joakim

[V Mad]

As much as I like the BMW 6, for this project the stag must have a V8

The GM350 is a great deal but its heavier than the Ford Windsor, not sure by how much, although it's tempting.

[stag8manod]

The Aussie Leyland P76 had a 4.4L (long stroke) version of the 3.5 Rover. Several Stags he.re in NZ have them fitted and go well. If your changing how about a Toyota Soarer 4.0 quad cam 32v.
Cheers Ian A