Esprit Turbo project car - part3 - the further continuation

[Lotusfab]

Have just measured the S1 centre hole it has a 4/100 PCD the hole diameter is 63mm. Believe the early dry sump should be the same as the bolt holes are very close to the opening and I have the original centre cap? BBS are probably a larger diameter, will measure tomorrow.

[RichardJGC]

This is a pic of my Lotus 4 stud hub with/without the snug fitting 70mm centre cap. They do get close to the bolts on the 4 stud version but ok on the 5 stud.

The wheel then fits over this retaining it all. They are not 'push in' from the front face like the plastic caps.

 

[Lotusfab]

I've just taken the spare wheel out and had a job to put it back! Richard is spot on there is a taper. The front of the opening is 63mm for about 4 mm deep then about a 45 degree angle to 70 mm for the rest of the depth? The centre cap fits from behind like Richard said. I like the centre caps Richard, they look new but exactly like the originals, where did you buy them? 

[Andyww]

28 minutes ago, RichardJGC said:

 

The bolt holes also align with the 'points' of the spokes though ironically I do have a pair which were incorrectly machined that are offset.

 

 

Oops well spotted! Completely forgot about that, will correct.

So I am not sure about this centre hole issue. If we want to fit these in place of BBS wheels on the same hubs can we use the metal caps? I am suspecting not.

[RichardJGC]

I got them from Mark at Stock Coachworks. I believe he had a batch done for his Essex.

[Lotusfab]

Would have to modify the cap design and maybe glue them or friction fit or both? Will measure the BBS tomorrow unless someone already has the answer?

Ahh Mark told me he had made a batch, very nice.

[RichardJGC]

1 minute ago, Andyww said:

Oops well spotted! Completely forgot about that, will correct.

So I am not sure about this centre hole issue. If we want to fit these in place of BBS wheels on the same hubs can we use the metal caps? I am suspecting not.

Andy....it may be a case of finding out the smallest hole required and making them like that. 

I have seen these used in both 4 and 5 stud versions with the plastic centre caps which push in and some may wish to go down that route.

Those of us which prefer the spun alloy caps with the larger diameter may have to get the centres opened out a bit?

I'd be just grateful if some were made available again whatever the centre hole size. :-)

[RichardJGC]

6 minutes ago, Andyww said:

Oops well spotted! Completely forgot about that, will correct.

So I am not sure about this centre hole issue. If we want to fit these in place of BBS wheels on the same hubs can we use the metal caps? I am suspecting not.

Andy....the set Mike had which were gold 5 stud versions did have the same 71mm diameter hole. I think the rears of all these wheels are 70/71mm but the section through the wheel alters near the front and reduces to a size suitable for the plastic centre caps where used....if that makes sense. (a stepped hole of two different diameters with 70 at the rear to fit over the hub centre)

[Lotusfab]

Andy, that sounds similar to the hub I gave you?

[Lotusfab]

The four stud version uses these.

[RichardJGC]

16 minutes ago, Lotusfab said:

The four stud version uses these.

Fabian....mine uses these ones.

Im not sure if there is a definitive Compomotive. I've seen many variances.

 

[Andyww]

1 hour ago, Lotusfab said:

Andy, that sounds similar to the hub I gave you?

Yes that has 58mm diameter on the inside and 71 on the outside. So what is the diameter of the BBS centres?

[Lotusfab]

Hi Andy will measure them later.

[silverfrost]

If its the hub bore on the BBS wheels its 71mm iirc     I would say keep the specs to the lotus comps and owners can just machine the later five studs hubs down imo. 

[Andyww]

I think at this point I will go with 71mm straight through. The plastic caps will then fit and there might be a possibility of getting metal caps made which push in from the outside.

This can be changed later anyway. At first I want to check the thing can be made at all!

Also will go with the BBS wheel bolt shoulder angle at this point although not sure what that is either yet.

[RichardJGC]

Good move. I think that will cater for the majority of what people are after. With a 71mm straight through hole and a 4mm chamfer on the back they will accommodate the original centre caps.

Im sure Supaspin could make some correct alloy caps.

[silverfrost]

Good idea Andy,  I will try and find out out what radius the wheel bolt is cut at, off memory there are two types of radius cuts for alloy wheels anyway. 

[Lotusfab]

Just measured the BBS cover 71 mm I think is correct. Can't get the wheels off to check how the bore in the centre is made as the car is jacked up.

Presumably they can be made with a central locating hole and everything drilled and machined afterwards?

[Andyww]

I have sent this to them to see what they say:

 

 

[RichardJGC]

1 hour ago, Andyww said:

I have sent this to them to see what they say:

 

 

Looks fantastic Andy. 

Had it in mind to CAD that up so I could print it off at 1:8 scale on my 3D printer. First thing I did print was some 1:8 radius arms...just because I could.

[Lotusfab]

That's spot on Andy, welll done and thank you! 

[Lotusfab]

My project seems to be reversing, I have now stripped out the fuel system, gear linkages, cooling pipes, Header tank Air box and most of the upper part of the induction system!☹️☹️☹️☹️☹️☹️ You have to break some eggs to make an omlette(I Hope!). 

[RichardJGC]

It might feel like it's going backwards but every hour you spend on it is an hour closer to it being done. You've done a lot in a short time.

[Lotusfab]

It was rebuilt according to the seller by an historic F1 mechanic and I have receipts for parts. I have run it and it was running very nicely till the Turbo went. Apprently it had to be moved from the workshop at short notice, so maybe a rush to put it back together? The lower half oil pumps,gaskets,camshafts and pistons(borescope) look,pretty good or new. It started and ran perfectly without any spitting or backfires, which means it must have been run and set up. The distributor looks new.  The carbs and upper part all look newly rebuilt. It must have been run on a bench as the fuel system was shot! Then put back into the car in a hurry as the gearchange had not been set up just assembled. No effort has been put into the plenum bits and they are greasy. As are the camshaft covers which wer the wrong way round.  I've nearly got the engine bay clean enough for a black epoxy coating. Those rivnuts are still causing problems. I had to saw of three of the four holding the water expansion tank. I'm looking forward to drilling them out and replacing them!☹️☹️☹️ I've already replaced 10 of them and have had to order 10 more! I've been cleaning for the last week and it still not done. The cooling pipes need attention thevhave been put on without any cleaning. Now the weather is warmer I'm hoping to get more done. Hoping to get it running and an MOT for the summer. It will be an eyesore paint wise but hopefully I will get the mechanics all tested before a total nut and bolt.

[silverfrost]

You are still making good progress Fabian,  Eyesore paintwork is not a drama in my eyes, better to have a running, road going esprit and have the paintwork on the back burner as you are doing for another time,  At least this way you can get it all sorted before the spray job,  nothing worse than spannering on a car that has recently been painted as accidnet can and will awlays happen.  

Once all the black bumpers, wing mirrors and rear lourve have been freshly painted, i would think a hard going cut and polish would go a long way to the car looking decent for a while, as you dont have to worry about cutting away to much paint as its getting painted in the future anyway 

Who knows, the way things are going on the comp front sesign wise, you could be rollin on freshly produced comps for the mot