Stroke of Genius

I remember an article you did a couple years ago about turning a Poncho 400 into a 455. Now I can't find that article. Where can I get that 455 crank for the 400?

Keith Norton
Via Internet

Rocky Rotella responds: Since installing long-stroke crankshafts has become popular in today's hobby and we've covered it many times in recent years, it's difficult to know which article you are referencing. Accordingly, I'll quickly cover the basics and provide you with what I feel may be your best option.

Installing any crankshaft with 3.25-inch-diameter main journals (like the 455) into a block originally designed for 3-inch main journals (like the 400) once required machining the journal to an undersize of 3 inches. Because the width of the thrust surface differs on the original applications, some additional modification to the crank was also required, and that was generally time consuming and costly.

Fortunately, companies like Eagle Specialty Products (ESP; have made the process much simpler and cost effective. ESP offers cast and forged crankshafts with a stroke length of 4.25 inch for the 400 block. That allows you to easily increase the displacement of your 400 to 461 or 467 ci depending upon the final overbore.

ESP's cast crank (PN 104004250) is likely the best value. It's rated to 700 hp and sells for less than $300 from most Pontiac performance retailers. If you plan on running your engine hard, the difference in stepping up to a forged crankshaft (PN 440042506700) is less than $500, and I consider it cheap insurance as the forging is much more durable in my opinion.

While you can purchase a 4.21-inch-length forging (PN 440042106625) that accepts stock-length Pontiac connecting rods and pistons, you'll find the 4.25-inch-length units are the easiest to obtain. They do, however, have 2.20-inch connecting-rod journals, which require the use of big-block Chevy-type connecting rods and custom pistons.

Whether you decide on a casting or forging, likely the wisest purchase is a complete rotating assembly that includes everything needed for installation into your 400 block, including piston rings and bearings. Many of the Pontiac-specific engine builders found in this magazine can provide the exact kit you need, with prices starting at less than $1,600. Any competent local machine shop should be able to machine your 400 block for an easy install.

Serving it Rare

I stumbled across a 1974 Grand Am with a 400/four-speed, and I'm trying to find production numbers on it. Can you point me in the right direction? I know this is a rare car, maybe even ultra rare!

Todd Nicewonger
Bloomsburg, Pennsylvania

Rocky Rotella responds: The production numbers presently available to the hobby disclose only the total number of M20 four-speed manual transmissions installed into the entire A-body lineup that model year: 833 units. Based on the Grand Am's performance persona, I would guess it represents a greater majority of that total, but I presently have no way of substantiating it. No matter how you look at it, you have a very rare Pontiac, one definitely worth saving.

Return to Sender

The Jan. 2014 issue of HPP included an article titled “Top Tuning Secrets for Pontiacs” and listed an address to H-O Racing for ordering two books (Heavy Duty Parts and Specifications for Pontiac and Pontiac High-Performance Engine Design and Blueprint Assembly). I did so and my mail was returned. I looked on and found the books [listed], but [none] were available. Do you have an updated address, or know a way I can buy the books?

Valley Park, Missouri

Rocky Rotella responds: The article in the Jan. 2014 issue was a reprint of the article that put H-O Racing Specialties on the performance map in the early 1970s. It originally appeared in Popular Hot Rodding (Oct. 1973). The yellow box in the lower left corner of page 58 explains that this was HPP's tribute to fellow H-O Racing Specialties founder Kern Osterstock, who passed shortly before that. We apologize for any confusion.

Unfortunately, H-O Racing Specialties is no longer in business, so it's no surprise that your mail was returned. I checked with Craig Hendrickson, who is the other half of the H-O Racing Specialties team, to inquire about the availability of books. He operates the website, which tells the company's story and accomplishments, but he doesn't sell its books any longer. However, Classic Industries currently sells a reprint of Heavy Duty Parts and Specifications for Pontiac (www.classic, PN L1893, $13.99). Internet auction sites are likely the best sources to find H-O Racing's other book, Pontiac High-Performance Engine Design and Blueprint Assembly, and you'll probably have to settle for used examples.

I think all of H-O Racing Specialties' publications are well-written, easy to read, and have accurate facts. I consider either of these books an excellent resource and a must-have for any Pontiac performance enthusiast's library.

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