Board logo

V8 Pulley Probs
Julian B - 12/12/03 at 03:42 PM

Hi

I am rebuilding a rover V8 to fit into a Dax Rush chassis and i have come up against the following problems

To fit the engine in the limited space you need to move the belt that powers the water pump and alternator back towards the engine. This allows it to clear two diagonal chassis tubes.
I have asked RPI engineering about this and they can sell me the bits to achieve this but i will be £200 down, gulp.
DJ Sports cars (dax) have suggested that an old P6 bottom pulley will get me part of the way through the problem and making up a top hat affair for the water pump pulley sorts out that problem but i still have to get a different alternator bracket to move that into line.
Has any one else come up against this problem? I'm thinking that if i have to go to all of this effort to make the belt fit , what’s the point of using a huffing great big alternator, and why not swap it out for a nice small and lightweight unit from a Micra or the like. Has anyone done this?

Cheers again

Julian Brewer
Cumbria


Simon - 12/12/03 at 04:54 PM

Julian

Have a look at:

http://www.hoverd.org/Tim/Dax/build_frames.html

There's a lot to read but you may find something helpful if there!

ATB

Simon


mackie - 12/12/03 at 05:36 PM

Good build diary, that!


theconrodkid - 12/12/03 at 07:22 PM

took me an hour to read all of that,he did have some build probs didnt he,good job ive got an MK


Julian B - 13/12/03 at 10:15 AM

Thanks for the info

It’s very very helpful

Cheers


P4 - 20/12/03 at 07:16 PM

Hi,

I have a cobra with a Rover engine. I had to move the alt. to the opposite side. When I reseach the bracketing for the alt. I found that the range rover Sdi and P6 had 4 variations of bracket. So its worth looking round. In the end I fabricated on out of 0.25" flat steel It only took a couple of hours. If you want I will photo it and send you a copy.


Jon Ison - 20/12/03 at 07:46 PM

not read the build diary above but cant you move a chassis rail ?

maybe not, just a thought.


mackie - 20/12/03 at 09:30 PM

We've been considering just making the engine bay longer. I know Craig has managed to fit it in without shortening the front cover but did have to make tunnel mods to fit it as far back as possible. I'm not 100% but I think our front cover is longer seeing as our car will have had the extra belt for A/C and/or PAS (it's from a Vitesse).
Ofcourse altering the chassis to give 50mm or so extra length would mess up the geometry but we have reasonable clue about this so possibly not a problem...


craig1410 - 20/12/03 at 11:04 PM

Hi,
A friend of mine has just completed fitting his alternator on the opposite side to normal by making up his own bracket and then using an idler pulley to deflect the belt away from the offending chassis tubes. I can probably get more details if you need them. He is using an SD1 engine with standard covers, pulleys etc.

I was thinking of using the power steering crank pulley (the one closest to the block) and just adapting the power steering mounting bracket to suit the alternator. The power steering crank pulley is a little bit smaller than the one for the alternator so it would run a little bit slow but my calculations state that at idle speed of 750engine RPM the alternator would still be spinning at 1700RPM instead of the 2000RPM it would normally be spinning at.

The only problem is that, with the alternator on the other pulley, how do I tension the water pump to crank belt? I intend to use an idler pulley like those which you get on timing belts, to tension the belt by pressing on the back of it. There is even an ideal mounting point for this idler pulley where the standard alternator adjustable mount is fixed. Again I can give more detail if you can't see what I'm getting at.

I hope this helps to give you another option.

Cheers,
Craig.


craig1410 - 20/12/03 at 11:06 PM

Mackie,
I'd be surprised if your front cover is any different to mine as I think all SD1's used the same cover. Let me know if you want me to measure anything on my chassis/engine.

I'd think very carefully before lengthening the engine bay as it will probably mean that you will need to make your own bodywork...

Cheers,
Craig.


mackie - 21/12/03 at 01:26 AM

I just did a very rough measurement of the engine from the tip of the water pump shaft on the front to the back of the starter motor bulge on the bellhousing and it's about 900mm which is longer than the standard engine bay, all very rough though. Looking at your pictures our pump seems longer, and EFI engines do have a different variant.
As for bodywork, we were going to make our own anyway I think.
Now the question is, do we get a P6 type pump and associated pulleys or do we build a longer chassis. The latter is probably cheaper but would require custom suspension stuff design.


blueshift - 21/12/03 at 03:40 AM

I have been playing around with lengthening the engine bay in solidworks and suspension geometry should not be a problem. basically nothing has to change but the FU1/2 top inset which are not specified in book anyway and we'd probably want to set with the help of a jig.

I would like to find out more about how nosecones attach though, I haven't seen one in the flesh. there's an interesting thread on here with comments by the great McSorley about lengthening and sizing the engine bay based on the size of the nosecone..


craig1410 - 21/12/03 at 02:29 PM

Mackie,
I cut the end off my water pump spindle which may account for some of the difference. Also, the starter motor bulge goes down the tunnel on my car which may account for a bit more.

The water pump spindle can be shortened as it is only used as a mounting point for the viscous fan and you ain't going to be using that I suspect. By the way, use a nice thin angle grinder cutting disc for this as the metal is extremely hard and a hacksaw blade just skids off. You can cut a few mm worth into it before you hit the very hard metal which I think must come from the planet Krypton or something as it is very very hard...

I can't really measure my entire engine in the way that you did but I'll take a couple of other measurements which should help. I'll post them later.

By the way, are you really sure that you want to make your own bodywork? It is a big undertaking and will by all accounts actually cost more and yield poorer results than if you just bought some stuff from the likes of GTS Tuning. Are you aware that Darren (GTS) is currently designing some +4" bodywork? He's also thinking of making it +1" taller as well to clear the likes of the Pinto and Rover engines. Drop him an email to add you name to those who are interested if you are indeed interested as this may speed the process.

Cheers,
Craig.


mackie - 21/12/03 at 03:15 PM

Craig. How far is the bellhousing mating face away from the front bulkhead? Your site says it's 93mm but that was a while back now.
I've made a rather crude CAD model of the engine and it looks like it should fit with the nose chopped but I'm not 100% on that until i've properly measured it.
Noted about bodywork, although a +4 nose would still probably fit a 50mm longer chassis without too many problems.


craig1410 - 21/12/03 at 05:49 PM

Mackie,
I'll need to get back to you tomorrow night about the measurements as I'm going out in an hour and have still to get fed and get changed. I'll measure it tomorrow and report back.

Cheers,
Craig.


blueshift - 21/12/03 at 10:17 PM

quote:
Originally posted by mackie
Noted about bodywork, although a +4 nose would still probably fit a 50mm longer chassis without too many problems.

Should not be a problem, that's what the mcsorley posts were about. We'll just need a custom bonnet, either home-done grp or ally with a riveted / bonded on bulge, to clear the plenum.