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skiprat
11-04-08, 01:56 PM
Hi all,

Having just purchased a Pilgrim Sumo with a RV8, I'm happy overall with the car, but just need more power. I've heard of some Robin Hood guys putting bike carbs on their Pintos and Vauxhall based bars to increase fuel flow, but wonder if anyone has attempted this on a rover V8? I'd really appreciate any advice you may have on this subject as to bhp increase on standard block, cost for conversion, pitfalls, and overall reliability.
I could of course swap out for a big clock, but funds unfortunately don't allow this.

Thanks
Simon

v8steve007
11-04-08, 02:15 PM
The only gain putting in a big CLOCK is more miles per HOUR lol ........
sorry couldnt resist that .

dingocooke
11-04-08, 02:17 PM
By the time youve bought the carbs, made a manifold, built a swirl pot (bike carbs arent designed to cope with lateral G) then spent time on the dyno, bought slides, jets needles needle jets etc etc Im sure it would be cheaper to have upgraded the RV8 using more traditional means; JRV8 should be able to help.

re the Robin hood people doing it; Ive yet to hear of a a car engine with bike carbs that actually makes more power than an engine set up with relevant carburetion built for the engine.

skiprat
11-04-08, 02:33 PM
Cheers Steve, I've contacted JRV8 for more info.
Simon

Miket
11-04-08, 03:20 PM
If you are still on SU's, the Webber 500 kit is the best thing you can get to increase the bhp. ;)

RPi Engineering - V8 Engine - Carburetion and fuel Injection (http://www.v8engines.com/carbs-1.htm)

Sidecarbod
11-04-08, 03:20 PM
If you can supply some info on your current RV8 I'm sure that there are people on the forum who can advice how to upgrade it.

Bike carbs may give you more power once the head flow rate is so high that more traditional carburation methods are stuggling but it would not be the first thing that I'd bolt on. (Even then quad twin choke webers would give you better chance of getting it running).

The RV8 is tuned in the normal 4 stroke way, cam, skimmed and flowed heads, better inlet manifold, better exhaust system, etc, etc.

The best method (I know this because this is what I did) is to stick a bigger RV8 in the chassis! (All the stuff that I bolted onto the 3.5 such as heads etc all worked much better with bigger lungs pumping away underneath).

One thing that I must warn you about, well two actually:-

1. BHP is additive
2. Tuning RV8's costs alot of money.
3. Enough power is NEVER enough! (Three things actually! :-D)

Good luck, speak to Jim and be careful of "bargins" on ebay, there are issues with some of the RV8 blocks.

Buy Des Hammills book on the Rover lump, you would be mad to start down the tuning road without reading it first.

HTH,

Pete

chedz
11-04-08, 03:50 PM
Hi Simon, if you post some details of what you have already someone can advise on the most effective way to get some more bhp for less $$$$'s. (not me though ;))

Are you running standard straight out of a rover engine or has it been doctored already, types of carb, inlet manifold, exhaust, comp ratio etc.

You may find there's a cheap way to make a nice jump in performance.

Cheers

G

TINKA
11-04-08, 04:30 PM
The best heads is always a good place to start along with a good inlet manifold, chiefly because if you do decide to upgrade later these can be transferred across so you won’t be wasting your money. :D :D

As has been said it does cost to get really big gains but it can be done Tony has done a really good job with his try dropping him a PM and see what he has fitted, don't think he spent a fortune on it either. :D

demus
11-04-08, 04:34 PM
Hi Simon,

If you are looking for a tasty carb setup, I'd certainly recomend quad Dellorto's, my RV8 goes like hell with them, not that bad to setup either, they wont come cheap though unless you can find some good second hand ones, but if your interested give John Eales a call at JE Developments.

Sidecarbod
11-04-08, 04:39 PM
Hi Simon,

If you are looking for a tasty carb setup, I'd certainly recomend quad Dellorto's, my RV8 goes like hell with them, not that bad to setup either, they wont come cheap though unless you can find some good second hand ones, but if your interested give John Eales a call at JE Developments.


Craggle had some but I still think they are a bit of waste on an otherwise standard motor. (assuming that it is standard)

craggle
11-04-08, 04:42 PM
Still got them.

They are quad 45's on Rovercraft manifolds. Not for small engines though. Need at least 3.9 and you will need some decent heads to get the best out of them.

Craig.

bitsilly
11-04-08, 07:22 PM
I had quads on a boxer manifold on an RV8 and every bugger was always telling me to ditch them and add a Holly!
If you are taking the engine out and rebuilding it, think seriously about bigger bores (ie a new bigger block) as your first upgrade as you can rebuild it with all the stuff from the old one.
What a wonderful problem to have hey??

craggle
11-04-08, 07:26 PM
If you had the boxer manifold did you have the quad SU setup?

The type I was on about is the quad twin choke downdraft carbs like the picture.

Craig.

tonym
12-04-08, 03:36 AM
Phil Ringwood has put bike throttle bodies on his old RV8 (efi not carbs) check here for info (http://www.extraefi.co.uk/cobra/accobra.htm) The picture shows a john Eales engine with their version of multi throttle bodies