A little project for a YB transplant has interested me in which so many problems with transmission and installation etc.. could be solved if the engine ran in the opposite direction.

Apart form engine managment issues which I am fairly well up to speed on..LOL, what else would I need to change around to make this work.

Is it just a case of swapping the cams with each other and reversing the rods ????

Has anyone done this ?

Thanks in advance.

 

not an expert but exhaust and inlet manifolds bolting up differently??

 

would this not make your forward gears run in reverse?

 

What do you mean by "run backwards" ?

Do you mean swap the inlet for the exhaust, like on a touring car Vauxhall Cavalier XE engine but the engine rotates the same direction still, or do you mean the engine physically rotating in the opposite direction?
(ie like a ITR DC2 honda engine)

The two are very different animals, I can give you some pretty good pointers on either, but cant be bothered to type out for both when one wont be needed so please be a bit clearer about what you want to do.

 

exhaust and inlet valves are different aswell?? sorry to go off track but if you could do it, could you in theory build a left hand drive cossie that was a complete mirror image of a left hand drive??

 

No, they stay in the same place

Thats the idea

(I know this is an issue but I am not worried about this at this point in time)


Chip,

Keeping the engine layout the same..Just making it run the opposite direction.


MAybe but thats not what I want !

 

your starter motor would need to be reversed for a start

 

now i understand, ignore all previous replies

 

Right, well to just run it backwards, the main things off the top of my head that are going to be an issue are:


Cambelt tensioner layout, the slack would be on the wrong side of the belt, so this will need changing

Starter motor, this will need changing internally to make it spin in the opposite direction

Cams, interesting one, given that all the YB profiles appear to me to be symmetrical im not convinced they would actually need changing other than the timing of them, not really looked into this enough to decide yet though, would need to just sit there and wind one over backwards and see what happens but I reckon it would just be a case of timing them differently.


Rods, the offset gudeon pin will be leaning the pistons the wrong way around, so rotate the piston and rod assembly the other way as the thrust side is now the opposite side.
You then potentially have the problem of the valve cutouts being the wrong way around, so you would need to check clearance of course.


Ive often thought about doing similar with a vauxhall engine (it would be the easiest way to 4wd my nova if I did so so) and thats the main things that Ive thought of so far that I would need to change to do so.

 

Just forget about it mate ... Would be a Nite-mare from start to finish.

Only engine's that can run the other way pretty easy are 2-stoker's.

 

That much I reckon we all agree on, lol


Would make far more sense to just use a honda engine instead if he needs one that rotates the other way around!

 

why would you need the engine to rotate the other way?

 

i always presumed, that when you look at the engine, inlet on the right, exhaust on the left, the engine would rotate anti-clockwise and vice-versa

i presume this is not correct?

 

+1

i'm confused.com!

 

oilways and thrust angles and all sorts would be issues first and foremost

nothing wrong with running the engien the other way around once they are done

 

Not correct at all mate, zetec engines and YB engines both rotate the same way, and yet have the inlet and exhaust the other way around.

Some older engines like renault 5 turbos and minis have both manifolds on one side of the head too.

 

Oil pump is another major one too mate, it would be trying to suck the oil out of the galleries and put it back into the pump, likewise the water pump

Thats true of all the ancilirries of course, so the alternator too, and probably even the power steering if its still attached.

But I was assuming all of those external things he would deal with seperately anyway, as obivously pumps can be swapped to electric etc.

 

Slightly off topic, but are electric oil pumps available? And are they reliable etc?


*On topic mode* Simon, go on spill the beans, why do you want to do this? Is it a purely theoretical thing or a technical exercise?

 

cheers Chip, always wondered that

 

Would the head not work as it ... Keep the cam's spinning the right way and timed it right?

 

Yes they are, but I have never used one so cant comment on how well they work.
I would personally try and fit a pump designed to spin that way, and just accept that means a bit of machining rather than go electric myself, but then im a bit of a old fart and done even like to trust eletric water pumps

 

Yes I beleive it would, as per my earlier reply saying exactly that.

 

Cool, never knew that, cheers

And I would be of the same opinion as you

 

Changed my post .. didnt sound right off the top of my head ..

Could the cam's run the other way from the crank? Need an Idler somewhere above the cam's or below the crank?

 

the idler could be sorted just by running a longer belt and using some maths

the dizzy is sorted as it can run coil pack

as you've sugested, turning the pistons around will sort the running out

oil pump can be electric (or dry sump it)

even the timing issues could be sorted just by having the cps repositioned or electronicly fiddled with

and if there is no dizzy and no oil pump, there is a big puley in the way to use as a make shift tensioner

 

You would have to drive off the top of the crank pulley or from the bottom of the cam pulleys .. Cannot think of a way to re-route the belt?

 

Some interesting reading !

This is for the possibility of doing a mid engine conversion with the engine in a "south-north" configuration.

Dont want to say too much just yet as it isnt my car.


The only other thing I can think of here is the oil surge to the front of the engine under hard acceleration !

 

but with no oil pump or dizzy there is another pully you can use as the tensioner

but it would need the teeth ground off of it to make it viable

 

Yeah ... But how would you make the cam's turn the opposite of the Crank? Have to run a pulley above or below .. Cannot cross the belt.

 

Dark-Horse,

The cams would rotate backwards too.

I think swapping the cams over and retiming them "may" sort the issue as long as the lift for each shaft is acceptable.

Maybe...LOL

 

to run it the wrong way.. all the bolts would come loose and fall off.. you would have to thread parts all the other way also!

 

Why would you swap them over?

The inlet would still be the inlet, and the exhaust would still be the exhaust, so why swap them?

 

Chip,


To maintain the proper firing order.

I think from memory, the valve sequence is reverse on the cams if you compare them otherwise 2 standard cams would be interchangable.
I may be wrong as I havent any to hand to look at them !

Hope you see what I am getting at !

 

Both cams are in the same order 1-3-4-2

So swapping the exhuast cam for the inlet cam wont make any difference to that order.

And now would you want to as far as I can see.




Whats your reason for doing this, cause the amount of engineering involved is going to be very prohibitive cost wise?

Why not just use a honda engine that rotates that way anyway?

 

There is a much easier way to achieve what you want, which I assume is a YB rear mounted with the 4x4 box facing forward so that the front diff in its normal location drives the rear wheels and the rear diff drives the front -you just flip both the front and rear diffs over by 180 degrees to achieve forward motion through the entire gear range

 

do you want to instal the cosworth 4x4 drivetrain as it is but as per the 6r4 below

 

 

if u just fliped the diffs 180 then wouldnt u have most of the drive 2 the front wheels (being the rear diff?)

 

the diff is not what controls how much % of drive each diff gets, its the unit in the back of the gearbox that controls how much the front and rear diffs get

eg. 50/50 %split
25/65 %split

is this what you mean ?

 

percentages not your strong point Jimbo?