Rover V8 Heads and carbs

[classiclady]

Message from Russ
Have you meassured the CC of the Cylinder head yet and can you tell me what the compression ratio is.

[craggle]

Unfortunately not.

I will try to get it done sometime this week and will keep you posted

Craig.

[Mark T]

Craggle,

Are the heads and carbs still for sale ?

Would these go on to a 3.9 ?

Could I expect signifcant performance increases over that of my the Weber 500 and stage 2 head set-up

Cheers
Mark T

[craggle]

Hi Mark

Russ (RCCOB) was interested in the heads but I haven't yet got around to measuring the CC of the combustion chambers so haven't got back to him about them.

I still have the carbs.

Performance is something I've never tested as I haven't had them running. Reading the books about the Rover it has been said that these carbs are the best solution and allows more radical cams to be used. They should run quite happily as they are, on a 3.9.

You will need to organise a few other things like a thermostat housing, Air filters or ram pipes, and a way of getting vacuum to the servo brakes. Best way is a vacuum pump on the engine, alternator or an electric one.

I will get the heads measured and contact Russ again to see if he's still interested.

Cheers

Craig.

[Sidecarbod]

Originally Posted by Mark T

Craggle,

Are the heads and carbs still for sale ?

Would these go on to a 3.9 ?

Could I expect signifcant performance increases over that of my the Weber 500 and stage 2 head set-up

Cheers
Mark T

Mark,

I'm guessing that you are at least to a degree a BHP junky!!

With regards to the heads you have to remember that the stage number does not mean too much but it does give some sort of indication to whats been done. Stage II will be a clean up and a 3 angle valve seat job. Stage 3 or 4 should mean bigger valves and this is what you need.

The standard valve sizes were chosen to suit a road tuned 3.5 lump which had to give good low and mid range torque. The valve sizes effectively get worse as the engine's lungs get bigger!

In other word you should see more top end with the new heads and it should rev to 6K RPM. Nobody could tell you exactly how much more.
You might lose some low down torque so you need to accept this.

Does Craggle want a fair price? well to get my heads done to stage III cost round 800 quid! (and I got a discount!)

One last thing, chasing BHP become addictive and therefore expensive. To get the best out of the heads you need other stuff the be right. That could mean getting them skimmed. Also you may end up using adjustable pushrods so that the valve train is spot on. Oh how about vernier timing gears and chain so that the cam is spot on....see what I mean!

One other thing, You ought to port match the inlet manifold to the new heads...its easy to do but can take 1-2 days!

Pete.

PS Craig, we need to meet up so that we can burette them!

[Mark T]

Pete,

Now I've got the chassis set-up, I can use all the power available most of the time and no longer find it scary (Junky zone). Lets say I drive with keen enthusiasm ! I've no idea what BHP the engines putting out (3.9, kent 214 cam, stage 2 heads, weber 500, performer manifold, some history indicates balanced and gas flowed, lightened flywheel) 200BHP ? Anyway what ever the BHP is I need about the half as much again ! I was hoping that Graig's heads & carbs may be part of the solution, however I'm now thinking of getting a 4.6 - 5.3 short engine and use my current top end components, I'd be happy if I got 300BHP, feels about the right number. What ever I do will be over the Winter and would like to keep the budget for additions below about £1500.

Any recommendations are welcome however, I'd prefer to stick with a Rover V8 solution. may be somebody has a super charger laying around !

Cheers
Mark T

[Sidecarbod]

Originally Posted by Mark T

Pete,

Now I've got the chassis set-up, I can use all the power available most of the time and no longer find it scary (Junky zone). Lets say I drive with keen enthusiasm ! I've no idea what BHP the engines putting out (3.9, kent 214 cam, stage 2 heads, weber 500, performer manifold, some history indicates balanced and gas flowed, lightened flywheel) 200BHP ? Anyway what ever the BHP is I need about the half as much again ! I was hoping that Graig's heads & carbs may be part of the solution, however I'm now thinking of getting a 4.6 - 5.3 short engine and use my current top end components, I'd be happy if I got 300BHP, feels about the right number. What ever I do will be over the Winter and would like to keep the budget for additions below about £1500.

Any recommendations are welcome however, I'd prefer to stick with a Rover V8 solution. may be somebody has a super charger laying around !

Cheers
Mark T

Hi Mark,

I know what you mean about BHP, enough is never enough!

I started with a standard 3.5 that I gradually tuned up, in the end is scrapped the block and stuck my heads on a 4.6 block, the performance is not too bad now!

I reckon that your motor may well be making a bit more than 200 BHP but at the end of the day the number is just a number, if you feel that you need more then you won't be happy until you get it. I understand why you want to stick with an RV8, going for another make has a lot of hidden costs, like engine mounts, exhaust headers, manifold, gearbox!, etc.

Your heads will be OK with a 4.6 block but the valves are getting a bit on the small side for the bigger blocks, this has the effect of boosting the mid range but restricting the top end and compressing the rev range some what. I guess it all depends on your budget. The RV8 is not the cheapest V8 to tune.

There are some issues with all of the bigger RV8 blocks, I suggest that you get a copy of Des Hammills book on tuning Rover V8 lumps, it's all in there! (I really can't recommend this book enough)

My motor has stage III heads a piper 285 cam, port matched edelbrock performer manifold, webber 500 carb, skimmed heads giving 10:1 CR, adjustable pushrods to allow the preload to be setup, and fiddled about with ignition. Once I've finally built some decent headers I'll dyno the engine, I'm hoping for 285-300 BHP. (But with a shed load of low down torque)

1500 quid may be a little on the low side, you can't skimp on the block but having said that I did see that someone was flogging new "cosy" blocks for a grand! I can't quite believe it but there you go!

You could buy a real scrapper of a 4.6 block and top hat liner it for a grand but you'll still have to buy the pistons and stuff. I think that a 5.3 block will blow your budget away.

As your block is the same bore as the 4.6 it might be posible to fit a stroker crank but your could really do with a x bolt block which I don't think yours will be.

One good thing that you need to rememeber is that 300 BHP from a Rover lump is better than 300 from a yank lump as the motor weighs ALOT less!

Pete