It kind of looks like Grant and I missed our deadline for the Bumpside Build-Off-and yes I'm not calling it the Bulletside Build-Off anymore. That's the first revision in my game plan, and I'll get to the second one in a couple of paragraphs.

No doubt by now if there was anyone who showed up to the Goodguys show held in Scottsdale, Arizona, last November 16-18 to check out Grant Peterson's '68 F-100 from Classic Trucks or my '72 F-100, they were in for a little bit of surprise. Or maybe not. After all, it seemed everyone but Grant and I thought that we had bitten off a pretty big chunk (check out the latest edition of Classic Trucks to see where Grant is on his build). Well the Scottsdale deadline has come and gone, but that doesn't mean the Bumpside Build-Off is over. On the contrary, we have both gathered a new full head of steam, and the race is still on!

And now to the second deviation in my game plan: True to our motto that at Custom Classic Trucks we make the mistakes so that our readers don't have to, my initial plan had a slightly flawed premise. I figured since Grant was building a slammed truck with an open budget I'd take the super low-buck road with my jacked-up gasser. Instead of buying exactly what I needed to get the job done properly, I tried to rework and reuse as many stock parts as possible to save money. When I got to the stage of trying to soup up the stock 302 truck heads, things went completely sideways and I lost a lot valuable time-not to mention money that I didn't need to spend.

Before I get into discussing the RHS alloy heads we're featuring in this story, I'd like to reveal some of the problems that I ran into with the stock truck heads and why they ultimately had to be scrapped. It was a simple plan really. I called the folks at Lunati and explained that I was trying to extract as much horsepower as possible from the OE 302. It was decided that in addition to a mild Lunati camshaft to help pull the ponies out, a set of Lunati pushrods and roller tip rockers were in order. This is where the proverbial poop hit the fan. Everything would have been fine if the rocker arm studs in my stock heads had 3/8 fine threads at the top of their 3/8- inch shoulders, but this wasn't the case. The threads on my 302 truck heads choked down from a 3/8-inch shoulder to 5/16 inch.

I called my contact at Lunati and he thought I was crazy, or, at the very least, mistaken. I said, "No man, I know 5/16 fine threads when I see them. Do you have any 5/16-inch locknuts I can use to lash the roller tip rockers down?"

He returned to the phone after a few minutes and said, "No." That was as far as we got that day. I had to get back on other projects that we had going at the magazine, so I let the stock heads mari- nate in my gunk tank for a while. This was at the early stages of trying to get the top end back on the 302, and I was already about a month behind the eight ball before I could get back to it.

By the time I got to this point, several months had passed and my spies up at the tech center were telling me that Grant was really making major progress with his '68. The pressure was on more than ever, but I felt I was beginning to see some light at the end of the tunnel. I picked up an ARP rocker stud kit and thought my troubles would soon be over. Unfortunately, the light at the end of the tunnel turned out to be a train, as the stock 302 heads' days were numbered. The only thing standing between being able to install the ARP studs and finally being able to bolt the stock 302 heads back on was that the OEM pressedin rocker studs had to be pulled out, and then bigger holes drilled and then tapped to screw the ARP rocker studs back in on top of the Lunati guideplates. I tossed the Ford heads into the back of my '79 Big10 and dropped them off at the machine shop. It was about a week or so before I got a call to come up and take a look at my heads. When a machine shop tells you that you need to come up and take a look at something, it's never good. When they tried to pull them out, half of the bottleneck studs had sheared clean off in the heads, rendering them junk. It was a dirty shame, because my stock 302 heads were freshly rebuilt-complete with silicone bronze valveguides. I didn't even want to look at them again. I asked the machinist to throw them away. Then the search for another set of heads began.

Looking for a set of used Ford heads isn't as easy as finding a set of Chevy heads, especially if you're trying to do it on the cheap. Oddly enough though, my search ended when the Mopar freak that lives down the street from me coughed up a set his dad had prepped for a Mustang and then bailed out on. This pair of heads looked like they would work okay, so I broke them down and prepared to do a valve job. Unfortunately, the heads sat on my workbench for about another couple of months before I came to the realization that the low-buck route could potentially end up taking me years to finish my truck.

One of the good things about working in the Rod & Restoration group is that we have a magazine rack upstairs full of all of our company's latest titles. One of my favorite magazines (off and on) is Car Craft, this goes back to the '60s when they used to run a lot of custom car show coverage. Anyways, these days the guys at Car Craft are running a lot of good engine building tech, so I like to keep an eye on what they are up to. One of the recurring themes in particular is when they take an existing engine and throw a cam, carb, and heads, to wake it up. In the December '07 issue with a cover main blurb that read "Budget Boost" they ran a story on how to take a junkyard Ford 5.0 motor and make it produce 600 hp on pump gas. In the beginning I was only interested in what they did for heads on the engine, but in the back of my mind I was remembering that Grant mentioned he was looking to supercharge the Mod Motor in his '68-but before we get sidetracked let's talk about the heads I'm going to run on my 302-inch truck motor.

Finally, a weekend came up where I didn't have to be on the road, and I tore back into the head dilemma. I got back on the horn and told the Lunati guy that I discovered what I had on my heads were what the Ford guys called "bottleneck" studs (some other makes have them too). Plus, there was another issue that came up because I was dealing with an early 302. I would need to use Lunati guideplates to go along with the Lunati roller tip rockers (the early Fords use a design built into the stock rocker arm tips to guide the pushrods).

The heads Car Craft used on their 600-horse monster small-block engine were from Racing Head Service (RHS). However, before I took the bait I did a little research on my own and discovered that RHS would be a good way to go. Some of the facts that I uncovered were the RHS PN 35001-02 Ford heads with an 180cc runner, smaller than the available 215cc runner, are a better choice for a stock-block engine, because the smaller dimensions keep the velocity up. But even with the impressive low- to mid-lift flow characteristics of the 180cc runners, they are capable of flowing quite well with up to .535-inch lift. Since most of the time, especially with the Gear Vendors 8-speed RUG-TOD transmission I've already installed in the '72, the 302-inch engine will spend most of its life at around 2,000 rpm. Of course, with the 4.56:1 gears in the Moser rearend (2.47:1 final in 8th gear overdrive) that I've yet to install, there will be times when the little Ford truck motor will be screaming its head off, or should I say heads? Another contributing factor to my choice of the RHS heads is that they are available in aluminum. Opting for alloy heads was a no-brainer, they weigh much less than the original Ford cast-iron heads, plus they dissipate heat must faster. If this wasn't enough, they look better. One of the steps that must be taken on-no matter which Windsor engine a person installs the RHS heads on-is that the piston-to-valve clearance must be established. RHS specifies that there must be .080 inch for the intake valves and .100 inch for the exhaust. In the case of my 302-inch truck motor with the lowest compression pistons a small-block Ford engine came with, I think there's a good chance I will not need to clearance the pistons.

Now, getting back to the Car Craft budget-boost story and Grant's possible installation of a huffer on his truck, I'll let you guys know what I'm up to. The centrifugal supercharger that Car Craft used to produce up to 618 hp on their 5.0 small-block Ford was from ProCharger. Again, not taking anyone else's word for it, I did a little research and decided the ProCharger would be the best way for me to go for my application. At this point it should be noted that Car Craft's 5.0 engine with its 618hp figure isn't a reliable engine. In their words, "Hey! Don't small-block Fords start sawing themselves in half at around 600 hp?" It creates a pretty humorous image in one's mind, but it's not what I'm after. My next step was to call Dave Culver at ATI ProCharger and find out the best route for what I had planned. Although a part of my original game plan has been ditched, I'm retaining the idea that everything I buy for my '72 302-inch truck motor should be able to be transferred onto a bigger small-block Ford engine. This means everything that I have bought so far can be reinstalled on a 347, or even a 427-inch Windsor Ford. Getting back to my truck 302. From what I've seen other people do, I should be able to get around 400 reliable horsepower out of the engine.

It's not going to be in the next issue, but, as soon as I can, I intend to get all of these goodies bolted on to my engine and get the old girl up to the dyno. In the meantime, rest assured that Grant and I are feverishly working to outdo each other.

Accessible Technologies (ProCharger)
Dept 5.0
14801 W. 114th Terrace
KS  66215
Racing Head Service
Automotive Racing Products(ARP) YearOne
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