The Shelby American (Fall 2021)

known quantity but ZF builds very good gearboxes so it should be alright. The third possibility, of course, is an automatic box. Ford is working on a number of automatic transmissions. SMITH: Ford is working on both man- uals and automatics? MILES: No, just automatics. SMITH: It would seem that with the problems that are facing the car right now, I gather that for more power I thought of trying the 427, which would appeal to you. MILES: Well, there are a number of possible ways to go. The 289 is, by no means, at the end of its tether by far. It’s capable of a comfortable 380 horse- power or maybe four hundred plus. And that isn’t the end of the 289.We’re working on a couple of projects with the idea of getting more horsepower – another thirty or forty horsepower. SMITH: What approach... or can’t you talk about it? MILES: Not really; it’s no secret.We’re working heads. SMITH: Are these aluminum heads? MILES: No. We’re starting off from scratch with new heads with the sole idea of getting high power by changing the valve sizes around. SMITH: Would these new heads use the staggered valve system? I don’t know when I’m getting into secret areas... MILES: No, let’s put it like this: we have so many designs, of course; there’s no question of secrets. We’re just doing everything we can. We’re trying many designs. One of them may click or none of them may click. SMITH: Do any of them do away with rocker shafts? MILES: Yes. We’re trying almost every approach. Every approach ex- cept overhead cams, which is a little expensive at the moment.We’re trying to keep the weight of the engine down. This is one of the major objectives: to keep the weight down. Once you get into overhead cams and things like that the weight of the engine goes up. The other approach is to increase the size. We have had some 325 cubic-inch engines running with varying success. We had one at Daytona and it ran up to five hours before it broke. We want to find out what broke and why. SMITH: I notice that you’ve already indicated that with a 427 inch engine the weight would be 2,310 pounds. MILES: With a 5300cc car it would only weigh 2,100 lbs. If you went up to 427, you’ve got another 165 pounds. SMITH: How much more does the 427 weigh than the 289? With aluminum heads? MILES: With aluminum heads, like the ones we use in the Cobra, puts the weight up somewhere in order of 125 pounds. I’m not absolutely certain. We are having a car built with a 427 en- gine in it. SMITH: Being built in Dearborn? MILES: Yes, being built in Dearborn, being built by Roy Lunn at Ford. Of course they are having a problem put- ting in the 427 engine because the torque in that engine is enormous. SMITH: It’s tearing up the gearbox. MILES: Yes. SMITH: Has anybody looked at the new Hewland box, the LG500? Does that seem hold any promise? MILES: I don’t know. I don’t know if anybody’s looked at it or not. I think Phil Remington will be going over to England shortly and I know he will look at it when he finally gets over there. Hewland is a pretty sharp man. He knows his trade and he might prove a very good contact. SMITH: So, you don’t think there’s any question but that the basic chassis and suspension could cope with that kind of power, the kind of power you would get? Miles: I don’t think there’s any doubt about it all. It’s fantastically good. It’s a superb piece of design, very highly sophisticated and extremely compli- cated. It’s extremely subject to, ex- tremely susceptible to minor errors in assembly which create havoc with it. SMITH: It’s like a good watch. A dol- lar watch will run forever and you can bang it around. But with an expensive timepiece if you get a little spec of dirt in it... MILES: With the Cobra, for example, with the leaf spring Cobra we varied the front caster negative three and a half to seven degrees, depending on how you feel about, it and it doesn’t bother the road-holding a bit. With this car, it’s suspectible to minute de- grees of caster change. SMITH: Do you know, offhand, roughly what the suspension settings are for the GT40? MILES: No, I don’t. SMITH: Does it run much negative camber in the rear? MILES: I’m not sure. I’d have to look it up. I’ve written it down somewhere. Here it is: it’s set up with one degree negative camber at the front and six degrees caster and an aggregate toe- in of one-eighth of an inch. In the rear it has one degree negative camber with ten degree and thirty-minute caster and one-eighth toe. With a ride height of five and a quarter inches in back and four and three-quarters inches in front. SMITH: What are the adjustments on the shocks? MILES: Twelve clicks from “off.” In other words, you turn them off all the way and then turn them back twelve turns. SMITH: What is the total range of ad- justment? MILES: There are twenty-one turns. Twenty-one clicks. This will vary some, of course. All of these things are variable. The spring rate is variable. We have different springs for the car. SMITH: Do you have any information on spring rates? MILES: No, I don’t. SMITH: It’s certainly esoteric and I don’t know if I’ll even get into that in the article. MILES: It’s available, but I don’t have it. SMITH: The last thing... I can’t think of anything else to talk about, about the car, mechanically or technically or the changes that were made to it. Do you have any comment about, one item that might be coming from you is about the way Shelby is doing it which is also the way you’re doing it. And also, what it’s like to drive the car. MILES: When we first started with the car we had one advantage over most of other people who had played with the car. For example, Ford Ad- vanced Vehicles in England didn’t have the skilled personnel to do the The SHELBY AMERICAN Fall 2021 48