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Engine angle
CosKev3 - 25/12/13 at 08:36 PM

Hi all,
I've bought a unfinished build with a chassis that was built for a Zetec engine, I'm converting it to run a R1 engine.
So I've got the chance to mount the engine how I want, I'm after peoples experience/knowledge of the engine angles, pros/cons of mounting the engine straight in the chassis, or on a angle so the cam cover runs level with the top chassis rail like MK and Mac1 seem to mount all there bike engines.

thanks in advance for any help/info

designer - 25/12/13 at 08:44 PM

The engine should always be parallel to the centreline of the chassis.

danny keenan - 25/12/13 at 09:01 PM

Hi

If you want one of our engine cradles I could sell you one I have spare which we have from moving workshops you could have it for £50

Thanks Danny mk sportscars

mark chandler - 25/12/13 at 09:05 PM

Being pragmatic I would source the exhaust first, bolt to the engine then position as far back as you can & missing frame diagonals and uprights, just dropping it in may lead to customised headers = cost.

On BEC's it's common to follow the frame rail as it gets the prop shaft down the centre of the car, mines mounted this way and it's not a problem. If you want an example of misaligned prop shafts have a look at a classic range rover front prop, they do 200,000 miles without issue when greased correctly.

Regards Mark

[Edited on 25/12/13 by mark chandler]

Wheels244 - 25/12/13 at 10:04 PM

Danny - have you got one to fit a ZX12 and the chassis I'm picking up from you on the 28th ?

Thanks

Rob

Sorry to OP for thread hijack.

Hector.Brocklebank - 25/12/13 at 10:07 PM

quote:
Originally posted by mark chandler
Being pragmatic I would source the exhaust first, bolt to the engine then position as far back as you can & missing frame diagonals and uprights, just dropping it in may lead to customized headers = cost.

On BEC's it's common to follow the frame rail as it gets the prop shaft down the centre of the car, mines mounted this way and it's not a problem. If you want an example of misaligned prop shafts have a look at a classic range rover front prop, they do 200,000 miles without issue when greased correctly.

Regards Mark

[Edited on 25/12/13 by mark chandler]


+1 on this in the real world it would be nice to run the prop down the centre line but generally (with the nature of a bike engines output shaft) we can never get this sweet spot so you do what is required and live with it many have and they are still here.

CosKev3 - 25/12/13 at 11:37 PM

Cheers so far.

quote:
Originally posted by designer
The engine should always be parallel to the centreline of the chassis.


can you tell me more why you say this please?
As I say MK and Mac1 build there chassis for the engine to run in line with top chassis rail.

quote:
Originally posted by danny keenan
Hi

If you want one of our engine cradles I could sell you one I have spare which we have from moving workshops you could have it for £50

Thanks Danny mk sportscars


which R1 engine is it for please?
Can you tell me the reasons why you angle your bike engines in your cars please?

twybrow - 26/12/13 at 12:20 AM

I depends in your chassis, but I would not want to run an engine that gives a prop to engine angle of more than 7 degrees. This was the advice I was given by Bailey Morris. When I bought my part built car, the bike engine had been mounted parallel to the diagonal engine bay cross member (and the zorst had been made accordingly). It didn't look right to me, and this was confirmed by Bailey Morris (it was running at 12 degrees). So i remounted the engine and nodded the zorst and achieved about 4 degrees which looks much better and should allow the prop to last. My new engine was mounted as suggested above - I bought an exhaust, fitted it to the lump, then set about figuring out where and how it would sit. If I were doing another BEC install, I would use this approach again. My ZX12 lump sits right back on the engine bay, and I did not have to buy a custom exhaust.

It is your car - do your reading, talk to those in the know, and be happy in the decision you make.

CosKev3 - 26/12/13 at 11:14 AM

Ok cheers.
moving the engine around it looks 'right' to me sitting straight in the bay, crankcase running in line with the propshaft tunnel, but from what your saying I fear that would make the prop angle more than 7 degrees?

doing some more reading up and there are a fair few posts on here saying the prop adapter should be parallel to the diff drive flange?!?!?

sdh2903 - 26/12/13 at 11:58 AM

Just a quick note with regards to position of the engine, in a bec the heaviest single item is the driver who's weight sits towards the rear. I moved my r1 lump forward to get a bit of weight up front over the steering axle to give a bit more feel and better turn in.

daniel mason - 26/12/13 at 12:34 PM

on the caterham i had. when converting to bike power the passenger footwell needs shortening to get the engine further back in the chassis where its wider.this enables the output shaft to be relatively central in the tunnel with the engine square on.not following the angle of the top rail!. the results of these conversions speak for themselves! very very good handling cars

twybrow - 26/12/13 at 01:54 PM

I am on my phone, so I cannot post a drawing (there are plenty of LCB that explain this), but the flanges should be parallel. The engine can be offset from the diff, so that the angle of the prop us no more than 7 degrees
simples!

CosKev3 - 27/12/13 at 06:36 PM

Ok cheers