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1700 Crossflow
Sij - 31/5/10 at 12:56 PM

What is the safe maximum power that an 1700 xflow can take?

Alfa145 - 31/5/10 at 01:09 PM

depends on the internals, top spec internals can push 180bhp

DavidM - 31/5/10 at 01:25 PM

As above, it depends on the spec, but also how driveable you want it. Caterham's super sprint engine does 135 bhp and still very tractable, but above that and it'll start getting difficult to live with on a road car.

David

MikeRJ - 31/5/10 at 01:30 PM

quote:
Originally posted by Sij
What is the safe maximum power that an 1700 xflow can take?


Engines don't take power, they make it. Then you need to define "safe".

Sij - 31/5/10 at 02:13 PM

My engine has 140bhp at the Flywheel. Not sure what internals it has but it has twin choke Weber DCOE 40 carbs. What would I have to do to get some more power out of it?

MakeEverything - 31/5/10 at 03:35 PM

Depends how much money you have, and how reliable you want it.

I would have said that you wouldnt get much more than 200hp, but even then thats quite a hopeful figure.

prawnabie - 31/5/10 at 03:52 PM

Finding power higher up the revs is the next step, for that you will need steel internals.

Alfa145 - 31/5/10 at 06:09 PM

quote:
Originally posted by Sij
My engine has 140bhp at the Flywheel. Not sure what internals it has but it has twin choke Weber DCOE 40 carbs. What would I have to do to get some more power out of it?


Buy A Zetec, thats what I will be doing to my crossflow

David Jenkins - 31/5/10 at 09:26 PM

That's what I'll be doing to my x-flow, the next time it needs big money spent on it.

Don't get me wrong, I think the x-flow is a cracking engine that is easy to maintain, makes a great noise and is very useable - but a Zetec gives as much power out of the box as a x-flow does after tuning work - and you can still tune the Zetec if you want more power.

[Edited on 31/5/10 by David Jenkins]

norfolkluego - 31/5/10 at 09:42 PM

quote:
Originally posted by Sij
My engine has 140bhp at the Flywheel. Not sure what internals it has but it has twin choke Weber DCOE 40 carbs. What would I have to do to get some more power out of it?


If it is genuinely making 140 I would have thought it had already had a fair bit of work internally and anything else would be mega expensive. I had a Crossflow with twin 40s and a Burton A2 cam and I wouldn't have thought that was making much over a 100 (if it was making 140, the Zetec that's in there now is making over 200 !! [and it's not])

Chippy - 31/5/10 at 10:23 PM

To get the max power from an Xflow you will need to spend a couple of thousand, and at the end you will have an engine that will be useless on the road, great for racing but little else. The answer is to fit, (as has been said before), a Zetec plenty of power straight from the box, very reliable and you can get a new one for around £7 or £800, and it will fit straight on your existing gearbox. Just my opinion of course, final choice is up to you. Cheers Ray

MikeRJ - 1/6/10 at 09:38 AM

quote:
Originally posted by Sij
My engine has 140bhp at the Flywheel. Not sure what internals it has but it has twin choke Weber DCOE 40 carbs. What would I have to do to get some more power out of it?


Just to echo the others, you are already at quite a high state of tune for a crossflow (almost 60% more power than a 1600GT engine), so getting any significant increases in normally aspirated form will cost plenty of money and the engine won't be very nice to use on the road.

I have heard of the mythical 200bhp Crossflow from the likes of Mass etc. but to even approach this you will need a full steel bottom end, an exceptionally well gas flowed head, full race cam etc. and it won't be a long lived engine.

OTOH you could consider forced induction, either turbo or supercharging, but you will probably need to make some changes to the engines internals as you are likely running a high compression ratio and a fairly lumpy cam, neither of which are compatible with forced induction. It won't be a cheap exercise anyway.

Sij - 1/6/10 at 01:23 PM

Thanks for the thoughts guys. I will be sticking to what I have for now.

Does anyone know of a cheap place I can get the carbs tuned. In the West London area. Power engineering want £150 for a RR tune is that a fair price?