X-flow tuning

Author
Discussion

DavidP

Original Poster:

371 posts

279 months

Wednesday 27th March 2002
quotequote all
I own a live axle Caterham (circa 1988 build) fitted with a dry sump 1691cc x-flow. I believe it puts out just short of 130bhp. I am about to get some modifications done to improve the power (ideally 150-160 bhp). I intend to gas-flow and port the head (to the extent that it's not already done) and fit a race exhaust and increase the size of the radiator.

Does anyone know of any tips and tricks with this engine that I should bear in mind?

Thanks in anticipation.

bertie

8,566 posts

291 months

Wednesday 27th March 2002
quotequote all
Get someone very good to do the head work for you and choose your cam carefully.

Peter Burgess in Alfreton, Derbyshire is excelent and very reasonable but only does heads.

For full engine work John Noble in Chesterfield are excelent with cross flows and he can do as much or as little as you want.

DavidP

Original Poster:

371 posts

279 months

Thursday 28th March 2002
quotequote all
Thanks Bertie
Anyone know what a Filter King is and does?

bertie

8,566 posts

291 months

Thursday 28th March 2002
quotequote all
I think it's a fuel pressure regulator used to limit the fuel pressure to the carbs.

Old style mechanical pumps which is what most carbs were designed to work with give out only 2 to 3 psi, and most electric pumps give far more than this and need regulating to stop the extra pressure defeating the float chamber valves.

Unless of course I'm on a completely different device!!!

filmidget

682 posts

289 months

Thursday 28th March 2002
quotequote all
You sure about complete engines from Pete Burgess?

He built a complete 'fast road' engine for my Midget 1500 (right back from 'scrap' motor due to knackered bearings/rods/etc), including supplying components, machining, lightening/balancing and the subsequent setting up on the rolling road.

I have always been very impressed with his advice, work and service. Also by his straight forwardness and honesty - I was wondering about having my flywheel lightened and he pointed out, having had a look at it, that for the intended use it just wasn't worth spending the money.

Just don't judge the place by location or tidyness of the workshop!

EDIT: think you're right about the filter thing Bernie

Cheers, Phil

>> Edited by filmidget on Thursday 28th March 11:58

bertie

8,566 posts

291 months

Thursday 28th March 2002
quotequote all
quote:

You sure about complete engines from Pete Burgess?



I could easily be wrong, it wouldn't suprise me if he did complete enginnes.

quote:


I have always been very impressed with his advice, work and service. Also by his straight forwardness and honesty



Totaly agree, he's a very down to earth good egg type.

quote:


Just don't judge the place by location or tidyness of the workshop!



Very true, I nearly turned aroung and went away again the first time I went.
quote:


EDIT: think you're right about the filter thing Bernie




Who is this Bernie character???

Petrol_Head

7 posts

272 months

Thursday 28th March 2002
quotequote all
I think with just a new head and cam you will be limited to 145-150 bhp at a push.

What you may need is more revs which are available from a steel Crank and rods then 200 bhp is possible (NB. in theory !).

Have a chat to Roger King at the Seven Workshop near Ware I have been told he is the Dogs when it comes to X-Flow engines !.

Don't forget MAX bhp is not everything you could try a 3D Ignintion system or even injection with full engine management which will give you a better crisper engine all the way up the rev range.

filmidget

682 posts

289 months

Thursday 28th March 2002
quotequote all
Sorry Brenda

bertie

8,566 posts

291 months

Thursday 28th March 2002
quotequote all
quote:

I think with just a new head and cam you will be limited to 145-150 bhp at a push.




Quite true, a much easier, more reliable and cheaper way to get 160bhp plus is to swap the x flow for a 2 litre zetec which with a pair of 45 carbs and new cams gives 160 - 170bhp and much more torque.

Also given that it's a much newer engine it's lots less likely to leak oil, won't breathe out oil like a x flow and probably not go bang!