Winter Projects

[zefarelly]

Moi Gearard!

I flow tested the standard manifold, and the Ford competition one, then modified the standard manifold to make sure it flowed more than the cylinder head on each port, and the overall carburettor flange flowed more than any carburettor that would fit.

I then ran simulations with different carburettor sizes/flow rates to see what effect it had on torque curves and peak power

[Gerard C]

Originally Posted by zefarelly

Moi Gerard!

Cant believe someone did. It had to be you! Apart from your experience you have something more than many others, two stroke knowledge. When you see what it takes to have this kind of thing work properly when modified, then you can dare anything! It works with rotary engines I guess… I found a close relationship between water temp and power too. Bearing in mind that modern two stroke work fine at very very low temp…

By my experience I mean my stupidity… The best I did? Change the fan bearing after the engine assembly.
Thanks to Peter M, at last I understood that keeping the manual rack and pinion has not to be done!
From you and Mike B, I saw the nice "spacer" you put between the spring saddle and the spring. Some are available to correct the pinion angle but I'm looking for a machined one which could hold tight the axle to the leaf. Mike if its, again, not clear, please proceed! Thanks.

Just out of my curiosity, how does the racing manifold look like? Is it homologated under Grp1 appendix?

[Mike Bell]

Originally Posted by Gerard C

From you and Mike B, I saw the nice "spacer" you put between the spring saddle and the spring. Some are available to correct the pinion angle but I'm looking for a machined one which could hold tight the axle to the leaf. Mike if its, again, not clear, please proceed! Thanks.

Not sure if I’ve got any photos saved of the wedge spacers for the Gp1 RS2000, but they were specifically made/machined so that they located in the hole on the saddle. I found a thick spacer washer the correct diameter (or we made two- can’t remember!), and used a countersunk bolt through that, the spacer, and the spring. (Being single leaf there was a locating stud which was removed.) So the wedge/spacer was solidly mounted to the spring (unless the bolt sheared- HT good idea) and when the U bolts were tightened, the spacer washer located in the saddle hole. Obviously I’m talking Escort axle here, but presume the Capri axle saddles are the same?

To work out what the nose angle of the diff needed to be I used a spirit level app on an iPhone......

[Gerard C]

Originally Posted by Mike Bell

Obviously I’m talking Escort axle here, but presume the Capri axle saddles are the same?

'F course, Atlas axle for both. Pics I got them from here, really the place to visit, I'm serious. May be E.B will know who I'm talking about as an ex- Cortina driver, I was in contact with a suspension specialist in Australia to get "inverted eyes" leaves but the company has been sold at least once and couldn't find drawings to help. Talking about experience, from Ric W I was "obliged" to adjust the front end with toe in. Each time I did, meaning at least 5 attempts, I quickly sent my car out of the track. Now I stick to what I like, toe in, and say to Ric that I'm too old to drive his settings. Know what? He loves that! OK I've been thick head with castor, after thousands of laps with 911's. Capri and 911 are really different, what works with one has not to be reproduced with the other… It must be obvious for many but I like to check myself.

Mike, think we're talking about this kind of thing
https://www.speedwaymotors.com/Leaf-...hims,3354.html

[Gerard C]

Probably, John E met Renault Sport people at a time. I've been lucky enough to have a guided visit to the Viry Chatillon premises when clients had to deal with Mecachrome. Each time we've been coached by Jean Jacques His, a nice person (specially for a French!) Remember when F1 was using a V10 3500 cc? To test quickly new solutions, they had a single cylinder 350 cc engine. When it came to talk about "feeding", airbox shape and stuff, he had a smile. "We dont need a lot of pressure, we are focused on harmonic vibrations (not the good word but you'll get the picture) now" he said before adding "sometimes we find things we can't explain but if it works we keep them"! It was so nice that we decided to give him back a piston and a valve arrived inadvertently in our pockets! Just for fun we had made a vernier caliper (in paper to avoid the check at the entry) to try and find the stroke!
John, do you remember when the Renault V10 angle was a well kept secret?

[Gerard C]

Zef or Peter or you Mike, do you know how many rear leaves the GB Capris are running? Escort homologation is clear stating single leaf. Capri form is less clear, you can see several leaves on the pic, may be four. But here, someone says it must be… two! There we go, Chef! You know those days…

[zefarelly]

THe Mk1 Cortinas ( some) use a leaf spring 'wedge' to tip the diff nose down.

seems to work for me . . . I don't have radius arms or trickery and don't suffer from tramp.

the Competition Essex inlet manifold was a genuine Ford item but I don't know any detail . . . roughly speaking a standard manifold flowed 300 cfm, the competition one 500 . . . . a modified standard one flowed 400 ish. More importantly, the individual ports, I got up to 180 ish, which is notably more than the head. ie stop the restriction.

water temperature makes a big difference . . . on a dyno once I ran a 1500 pushrod engine, only made 125 bhp . . . water temp was 92 ( set for a 90's 16v Renault engine) I dropped it to 85 and instantly got 137 BHP.

[Mike Bell]

No Gerard, I don’t know how many leafs a Gp1 Capri spring has. Guess more than one as the ‘single leaf’ tapered spring is only available up to a certain poundage.

The axle wedge you showed link for is OK but wouldn’t have been as good for location as my home made ones. I’m sure you know this, but the reason for altering the diff nose angle is that it needs to match the engine/gearbox angle, otherwise the front and rear UJ rotations don’t match.....

Radius arms can be good but for racing maybe not so necessary as in rallying? I ran the Gp1 Escort with (homologated) alternative rear ARB, and never noticed any tramp.

[Gerard C]

What a good reading. Thank you very very much both. Not so many people like to share good experiences which is normal when a lot of work and of brain is involved. More than money which is involved too.

No Mike, I didn't realize it was about putting the engine/gearbox/shaft/pinion in line! Still I'm convinced that its more important with a yank tank pumping out circa 500 hp to avoid the "lift" effect (ascenseur in French)! The Capri runs a two part main shaft even though many have one part shaft made.

Zef, my water temp is around 75° C out the heads (oil being more) thanks to an appropriate thermostat and a massive rad (aluminium or copper). A good thing is to prevent the heat inside the engine bay to go up - quite a challenge! - you can bolt shields on the heads above the flanges. Or wrap them, which adds weight.
The flow figures you got make me dream, of course, and if I understand correctly your manifold can work with several different carbs', type and diameter. Did you notice the homologated air duct breathing behind the front end gril? I'm obliged to keep the original airbox too, which is a pain in the power!

Now you're building a Capri, you see that in principle we are allowed to use either tramp bars (MK1 and facelift) or an arb MK2/3 which main purpose is to help to locate the axle. "New" Grp 1,5 Capris seem to have the arb relocated under the axle, have to check if its permitted or beyond the limit. Depending on which way you read the papers, right to left or vice versa, may be its admitted to run both, tramp bars up and arb below…
As we all know, arb's diameters are free. In those conditions, having the axle moving up and down freely is a Quest in itself! I went back to original silent blocs at the end of the arb to avoid stress.
All this I presume send us back to what it takes building/restoring a race car, wandering from one compromise to another!

Thanks for the net pic! I saw your advert (RCD may be), did you sell it yet? Is it an Australian version as E.B had one?

[Mike Bell]

Originally Posted by Gerard C

No Mike, I didn't realize it was about putting the engine/gearbox/shaft/pinion in line! Still I'm convinced that its more important with a yank tank pumping out circa 500 hp to avoid the "lift" effect (ascenseur in French)! The Capri runs a two part main shaft even though many have one part shaft made.

Thanks for the net pic! I saw your advert (RCD may be), did you sell it yet? Is it an Australian version as E.B had one?

The RS2000 was sold well over a year ago. It was a UK spec car, but when Ford sold a few in Australia late in the model’s life, it was with rear ARB and ‘flat front’ body, so those mods were added to the homologation. If his plans come to fruition, the current owner of the Jagermeister car should have it at Goodwood MM in April.

A two part prop shaft almost gets over the alignment issue. The RS2 has a single piece shaft homologated as well, which is obviously stronger/better for competition use. Only way to avoid the alignment issue would be to use CV joints instead of normal UJs. If the front UJ is moving through a greater arc than the rear UJ, they fight each other and cause ‘wind up’ which makes the shaft vibrate. Believe me, it’s not nice!

[Gerard C]

Originally Posted by Mike Bell

If his plans come to fruition, the current owner of the Jagermeister car should have it at Goodwood MM in April.

Wish him all the best of course and hope he'll find the special RS airbox and a good manifold. Do you think he could match a front running Dolly? Or Capri…

Do you know people using this kind of stuff?
http://www.raceproducts.net/group-nc...its/index.html Yes, no homologation for those but looks nice. And easy to spot!

[Mike Bell]

Originally Posted by Gerard C

Wish him all the best of course and hope he'll find the special RS airbox and a good manifold. Do you think he could match a front running Dolly? Or Capri…

Do you know people using this kind of stuff?
http://www.raceproducts.net/group-nc...its/index.html Yes, no homologation for those but looks nice. And easy to spot!

I had a genuine Gp1 airbox which went to the new owner with the car. They restrict breathing a bit so the period trick was to cut holes in the underneath where they weren’t immediately seen!

Yes, easy to see negative camber where there shouldn’t be any! Peter M will know more about period Rovers, but I think Walkinshaw used CV joints at the inner halfshaft ends to achieve something similar to that kit you show.

[Gerard C]

Peter M already said that some Rovers were running crank axle and Capris too. Nowadays some Capris have a retubed axle plus an aluminium pig head which is absolutely not compliant. Not mentioning some engines being moved backward by 8 or more centimeters, a trick hard to spot if you dont have an original car in the area because you have to modify the bulkhead to keep a certain clearance… No more Grp1, 1,5 or even 2, this sends you car directly to Grp5 or Silhouette.
As to Uncle Tom, it will save time to list what he didn't use…

[Mike Bell]

Couple of years ago we were at a PA meeting with a British GT350 that was being run by the preparers. The boss couldn’t believe his eyes when he caught a glimpse of the engine position in one of the ‘regular’ cars......

[Gerard C]

Did you find a real Grp1 exhaust manifold for the new owner?
Among the things we can't get for a LHD Capri, are the exhaust manifold, the rack and pinion and the homologated aluminium clutch bell. The last one has the cable entry on its right side, should be on the left for a LHD. Do you know a company making bespoke clutch cables with Ford specific ends? Even if we have to send a new one to have it modified. Ric Wood has bells (no pun!) made.

[Gerard C]

Originally Posted by Mike Bell

Couple of years ago we were at a PA meeting with a British GT350 that was being run by the preparers.

I guess you already saw if not detailed a dark green/white strips 289. Registered as a Grp1, I can give you links showing clearly the car making ridiculous a 635 GrpA in the straight between Stavelot and Blanchimont. The Bimmer is a good one, slick shoes, its driver being one of the best in the said series. There is so much to learn from those videos…

[Mike Bell]

Originally Posted by Gerard C

Did you find a real Grp1 exhaust manifold for the new owner?
Among the things we can't get for a LHD Capri, are the exhaust manifold, the rack and pinion and the homologated aluminium clutch bell. The last one has the cable entry on its right side, should be on the left for a LHD. Do you know a company making bespoke clutch cables with Ford specific ends? Even if we have to send a new one to have it modified. Ric Wood has bells (no pun!) made.

The RS went with a normal cast manifold as well as the tubular one. Still not sure if the special ‘Group 1’ manifold rumoured to have been produced was just a myth.....

I found someone on eBay that made ford clutch cables to order, and purchased a longer one to give more exhaust clearance..... Worth a google search.

[Gerard C]

Ho no, no its not a myth, its real. Not only the diameters are different but the internal radiuses improve the flow. They dont go for cheap and are really thought after. Thanks, I'll google for the cable (cable tec may be)!

[Gerard C]

Is it possible to find Rimflow intake valves for the Essex. Are they worth?

[Gerard C]

Zef please are you able to source proper original Payen gaskets for the intake manifold? Those coming from a well known supplier are not so good. We didn't reshape the manifold to have it sitting on the heads yet. Is it mandatory?

[Peter Mallett]

Going back to rear springs, we ran single leaf, decambered and then adjusted stiffness with dampers. You can also run a lowered ARB if you use the fabricated drop links. Also it was permitted to use the fully floating drive shafts. The more leafs you run the more weight you have to control.

We ran up to 4 degrees negative camber, depending on tyres and a lot of negative castor. This was achieved by offset front ARB mountings. Also we have specially fabricated top mounts which allowed for both camber and castor.

30 seconds of toe-in.

For the engine we had specially designed pistons by JE.

Yes we used the power steering rack.

[Gerard C]

Voiceless… which doesn't mean I dont thank! I have to find out why each time I go for a lot of negative castor, she gets worse in the corners entry leading to hardly reach the apex. Manual states negative castor is 0.5 to 1,5°, going more than 4.5°/5° gives a lot of understeering atm.
Till now couldn't get more than 3° neg camber with non adjustable TCA's (Yoko or Toyo tires).
Was the use of fully floating half shafts a consequence of the remplacement of the drums by discs?

My first set of pistons was bespoke Arias I think. No Accralite available in the std bore dimensions (they are said sensible to overheating). The piston question is touchy because of the class limit.
I know you understand my - very - bad English what I mean is that if the chosen pistons need a huge clearance the risk is to land at circa 3034 cc… They check the bore not the piston diameter which is normal. Same thing with many others 6 cylinder, any overbore on a 2L 911 will send you above the mandatory 1999,99 limit!
Thanks again, you pointed the right "direction" giving me work for this winter. And may be more! Please go on.

PS You're a Chef and "King-Ford"! Hence the use of their briquets. I like your recipes, both food and Capri!

[Peter Mallett]

You get more understeer with castor in slow corners so you have to use the rear end. Castor is for fast bends and straight line stability. For additional camber we used the adjustable top mounts to fine tune the camber.
As I recall we ran about +30 thou bore. We were certainly within the permissible volume.

[Gerard C]

Originally Posted by Peter Mallett

You get more understeer with castor in slow corners so you have to use the rear end.

Indeed. Using the rear end is not so difficult, seems there is another steering hidden there! Did you adjust your settings depending on which track you were using? I guess 30" of toe in or zero is barely the same.
Right again, + 29 overbore is within permissible volume, less than 500 cc per barrel. I see that all Ric's engines' capacity are checked and sealed by Motuk official scrutineer now. A very good thing imho.

[Peter Mallett]

Running parallel front end is not good. As the car rolls the outside wheel points out, instead of straight. It also depends on the ARB setting but as a general rule toe in is best for RWD. Parallel for FWD.

Yes we adjusted damper and steering settings depending on circuit.

These things were permitted for the Capri whereas they aren't for the Rover. All due to the manufacturer certificates presented to the RAC by Ford but not by Rover.