C37 – Alpine V6 Conversion

by Gary Schotland with Larry Atkisson & Joe Rodriguez in the May 1996 RootesReview

Imagine an Alpine with performance that will blow the doors off a stock Tiger and embarrass more than a few modified ones: 300+ reliable horses, 0-60 in 5 seconds, and under 12 seconds in the quarter mile, all with the more balanced handling of an Alpine.

Stop dreaming. Such a machine does exist.

It is a turbo charged and inter-cooled version of the Ford 2.8 liter V6 so many Alpine owners, in search of a little kick in the pants and “something different,” have been talking about dropping into their cars.

This beast is the brainchild of Joe Rodriguez of Seattle, Washington, a die hard, Southern California-bred speed nut who has spent over ten years playing with Alpines and almost as many years turning his into both the ultimate sleeper and a nice, reliable long-distance cruiser (the two don’t have to be mutually exclusive). He could write a book about all the pimply-faced teenagers driving pumped up Camaros and Mustangs he has sent back to their playgrounds in tears. And during the course of his quest for a reliable, killer Alpine, Joe has engineered a kit which makes it easy for the average enthusiast who has a little mechanical ability to put a V6 in his/her Alpine. No cutting, welding, or fabricating custom headers and brackets through “reverse engineering.” To date, over a dozen kits are in service and they’re still going strong.

Sounds pretty good, but you’re not so sure you need 300 horsepower in your Alpine? That’s the beauty of this conversion and of Joe’s kit. He’s done all the hard work for you by designing and fabricating the installation kit. Depending on your priorities and the size of your wallet, your Alpine can be mild, wild, or anywhere in between. It’s all up to you.

So what does Joe’s kit include and how much does it cost? This neat little package includes custom-designed engine and transmission mounting brackets with rubber mounts, a pair of equally custom flow-optimized headers, and as much technical support as you need for only $750. This sounds like a lot, until you consider how much time, money, and aggravation you’ll save if you are a “whiz-bang” mechanic who thrives on challenges.

Ever try to have the guy at the local muffler shop bend and weld a few pipes to make a couple of headers for you when all he had was a few measurements to work with? At $30 – $40/hr, you can get to $750 in a hurry and the results are guaranteed to be less than optimal. And imagine how many times you’ll have to take the engine in and out of your car to test fit those muffler shop headers? That’s a lot of wasted weekends and money for cases of beer for your buddies. Get the picture? If the kit price hasn’t scared you off, read on …

Engine

The Ford 2.8 liter V6 for the conversion comes from the so called Mustang II, which was produced from 1974 to 1978, and from the German Ford Capri, which was produced from ’74 to’77. (Note: Ford’s 2.6 liter V6 from the ’72-’73 Capri cannot be used with this kit). By anyone’s measure, the Mustang II was the least attractive and wimpiest Mustang ever. Because of this, they are far from sought after by collectors. In other words, it won’t take much digging to find one with a donor engine at your local junkyard. Expect to pay about $100-200 for a rebuildable engine. Be very skeptical about paying a premium for a “rebuilt” engine. Assume you’re going to have to rebuild it. A basically stock rebuild by a shop should cost around $1000 including parts, or you could do it yourself and pay $500-$600 for all the parts and machine work (block boring, etc.). Rebuild parts are readily available from Performance Automotive Wholesale (P.A.W.) in California, among other sources. There were far fewer Capris imported, so you’ll be less likely to find one. If you do, expect to pay the same as for a Mustang because it offers no advantages.

Right out of the box, with its restrictive cast iron exhaust manifolds, smog equipment, very mild cam, and 2 barrel Holley carb, the 2.8 V6 produces 105 hp. No big deal. An Alpine puts out almost that much, right? Maybe on a good day when your Strombergs aren’t giving you fits, but as far as torque, it doesn’t even come close. Bolt on Joe’s headers and for a few hundred bucks more, install a little hotter cam, a remanufactured 390 CFM Holley 4 barrel, and shave the heads .030 to raise the compression from 8.0: 1 to 8.5: 1, and before you know it, the engine’s putting out a solid 150 hp. This is nearly as much power as a stock Tiger and more than enough to swiftly move an Alpine. And if you’re on a budget, this is probably the best route to take. When funds permit, you can easily do some head modifications to push out a few more ponies.

Beyond these upgrades, things start to get much more expensive. You could go with an even hotter cam, put in larger exhaust and intake valves, lighten the flywheel, raise the compression even more, port and polish the heads, or even add a turbo charger and intercooler. For example, to completely modify the heads would cost about $800 for a shop to do it. As always, the sky’s the limit.

Transmission

The least expensive transmission you can use is the Borg Warner 4 speed that originally came with the Mustang II. The Capri transmission cannot be used mainly due to clearance problems, but also because it’s not as well put together as the Mustang unit and probably can’t handle the power of a “hot” engine. The next step up is a Borg Warner T54 from a ’84 or later Thunderbird Turbo Coupe. Joe says this is a very worthwhile upgrade. Again, plenty of these should be available at your local junkyard. Expect to pay $100-$150 for a Mustang 4 speed and $250 and up for a T54 (more than adequate). For overkill you can go with a T5 out of a late model Mustang for $600+, but it has less than optimal gearing for the conversion.

Naturally, try to find a transmission with low mileage, and try to get the yard to give you some kind of guarantee. A reputable yard should.

Clutch & Clutch Hydraulics

With the Mustang II 4 speed, the stock Mustang II clutch and pressure plate are quite adequate. If you’re going with the T54 or T5, Joe recommends a stock Mustang II clutch and a McLeod hydraulic throwout bearing. The McLeod throwout bearing costs about $285. For the clutch master cylinder, you can stick with stock Alpine unit (5/8″ bore) or for more throw, change to a stock Tiger unit (3/4″ bore).

Cooling

Stock Alpines came with a two-row radiator, which in warmer climates provides inadequate cooling capacity. Thankfully, radiator technology has moved ahead in the last thirty years, so it is now possible for a mere $175-200 to greatly improve cooling by replacing your old core with a new three-row core. In addition, the inlet and outlet locations will need to be moved in order to accommodate the V6 plumbing. Any competent radiator shop should be able to easily handle all of this. Not only is the three-core radiator a nice upgrade for a stock Alpine, but it is absolutely required for the V6 conversion. Another nice addition is a Flexalite plastic fan for $20, which will be far superior to the stock fan, which tends to fatigue and break (I know from experience).

Steering

The steering system is kept stock except the center link rod that sits behind the engine must be modified so it sits back 0.5″ and 1″ higher. If you’re handy with a welder, Joe can instruct you how to fabricate a center link using tie rod ends from a Ford Fiesta, or he can have one made up for you for $125 complete (in addition to the basic kit cost).

Exhaust

This will have to be custom fabricated by a muffler shop at a cost of around $350. A system similar to the one used on a Tiger (2″ pipes, 2 oval mufflers, etc) is the best way to go. If you plan to go with a system similar to the Tiger’s, it might be possible (and more cost effective) to buy some of the parts for your muffler shop (such as the mufflers and tailpipes). For a little more money, consider going with an all stainless system which will probably never have to be replaced.

Electrical

A giant leap up the food chain is the Ford electronic ignition system originally supplied with the Mustang II. It’s very reliable and you won’t have to deal with breaker points. Joe strongly recommends it and can tell you exactly how to painlessly integrate this into your system.

Naturally, your stock tach must be recalibrated. Any other shop intimately familiar with Sunbeam instruments can probably recalibrate it for a nominal fee.

A Ford Fairmont or Maverick alternator (smaller and cheaper than a Mustang II) is an inexpensive way to go, or any number of GM alternators can be used just as easily, depending on your preference.

The stock temperature sending unit can be made to fit using a commonly available adapter.

Since it won’t be possible to use the original Alpine mechanical fuel pump, Joe recommends a good quality electric pump such as a Holley or Carter ($30-$50). It must be mounted underneath the car a bit lower than the gas tanks so fuel will gravity feed.

Differential & Suspension

The suspension can be left completely stock. If funds permit, consider installing performance shocks such as Konis or Spax and changing to polyurethane A-arm bushings.

With a budget conversion, it may be possible to stay with the stock rear end with a couple of minor performance modifications. However, if you like to drive your car hard, chances are the stock rear won’t last long. A logical and easy substitute is a stock Tiger rear, which can probably be had for around $300. Stock Tigers came with 2.88 gear ratio, but Joe strongly recommends changing this to a more optimal 3.31 ($200-$300). Another option is to shorten the axle tubes 3″ on a Ford Mustang II 8″ rear with a 3.55: 1 ratio (probably around $150 plus shortening charge).

Next, spend another $129 at your favorite hot rod mail order house for an adapter kit so the stock handbrake can be use with the new rear brakes.

The Bottom Line

If you’re going to do most of the work yourself, a basic conversion will run around $2000.

Depending on how much you want to use from the Mustang II, it might be more cost effective to buy an entire parts car for $300-$500 and then dispose of what you don’t use. You’ll be pushing close to $3000 if you’re going to have the engine rebuilt, add engine performance upgrades, or use a T5 transmission, among other things. As always, you can get as fancy as you want if your pockets are deep.

If you’re serious about the V6 conversion for your Alpine, take the path of least resistance by starting with a kit that will virtually guarantee results you’ll be both impressed with and proud of.

If you really want a Tiger, buy one, because you probably won’t save much by doing this conversion.