What is the best way to install new offy heads on my flathead? I thought I saw one time someone offer shoulder washers and bolts for Aluminum heads some place. thanks--spike
Speedway in Lincoln Neb has a kit, or you can use grade 8 hard washers and 7/16 hard nuts that you get at a quality hardware store, I use Caterpiller Hardware myself, but i am a. Cat mechanic. ... Speedway's e-mail, www.SpeedwayMotors.com Give them a try
New studs, HARD...VERY HARD Washers and torque as recommended by the Offy manufacturer.(it is less than a iron head) You will need to re-torque a couple of times after cool down and then periodically. Use the gaskets they recommend also. There are complete kit's available.
It all depends on whether you're running studs or bolts. With studs, it is a good idea to run the special 'insert washers' that ARP and others make. This does require that you machine the heads (tops of the bolt holes) for the insert area to slip down into the head. These type of washers do two things: a) They prevent galling of the edges of the aluminum bolt holes. b) They help you achieve a more accurate torque reading. I've always liked studs in high-performance flatheads - but they are more of a pain in the rear when putting heads on. Make sure you use a good thread sealer on the co**** thread that goes into the block (to keep them from leaking/seeping) and anti-seize on the outside of the studs - the whole length. Getting the heads back off can be a real challenge even with anti-seize in use. Typically I use ARP studs and fasteners - not the cheap **** that so many folks tend to sell these days. Many of the fastener kits have cheap Chinese hardware that truly isn't of high grade - but it is cheap. Torque: I usually go to 50 lbs (with ARP hardware) . . . some guys only go to 40 - 45. Make sure you re-torque the heads once the motor gets up to operating temperature. Then again once you've ran it for a few hours. Best of luck - post some pictures. B&S
Hey there Dale! I agree on the studs. ARP is good stuff but very expensive. The ones we stock are mfr'd in Michigan....they're very good quality. Same with our cadmium plated stud nuts and the hardened washers....all USA made. You can machine the tops of the heads (where the nuts go) to accept the hardened washers. Or you can purchase the extended length studs (about 1/8" longer) that provide the spacing needed for the washers and the nuts. We stock these too. Your torque specs are right on for aluminum heads. Plus the recommendation to retorque several times to make sure all is still at the 45-50 lbs.
You didn't ask, but for torque I use 65 foot lbs. Some folks use 55. Don't forget to use sealant on the threads.
Good hearing from you Mac! I'd not hesitate to purchase flathead parts from Mac - he is a stand up guy and is very p***ionate about all things flathead! As he noted - if you're not building a full-race, high-end motor, you'll save a lot of money by purchasing standard studs, washers, nuts - quality USA made stuff (from a known and trusted supplier). Also, Mac's studs and nuts will look more 'traditional' -- as ARP stuff looks like ARP (what can I say) . . . just a bit more modern looking. Thanks for letting us know about your parts availability . . .
I think these are a good idea with either studs or bolts, http://www.stefs.com/bandb/products/productpages/washerstep.htm. My thinking is that they help keep the bolt or stud centered in the hole helping to prevent galling or corrosion. You have to buy a special drill to install these.
Could you share that cat part #? or sell me some? Im a equip. mechanic and know how good cat stuff is.
What is the danger/benefit of re torquing aluminum heads months or even years down the track. I am talkin heads that havent leaked etc. Just to make sure all is tight. I really never hear about this. Just curious
Aluminum heads are thicker than the old iron heads, so you should switch to studs that are longer than the original bolts.
Hi there! I have more or less the same questions, got the Offenhauser studkit btw, 'Speedy Bill' wrote me somekind of manual for the mounting of the heads, but opposite to all other books etc, he advises to tighten from side to side, (left to the right or L 2 R) and not starting in the center 'x-ing' away with the tightening?? Also I'm a bit hesitant of spraypainting heatresistant aluminumpaint onto the headgaskets as they say. I'm somewhat afraid it could drip down into the cilinder when tightening? I have Edelbrock heads, an Offenhauser dual and a '47 Flattie type '59'.. picture: (the superdual intake wasn't mine)
Engine looks nice. When you support an early engine like yours with only the bellhousing bolts, there's a risk that the weight of the engine will snap the bellhousing and the engine will come crashing down. Use the attachment where you support the engine using the exhaust ports. Also, you let the aluminum paint dry on the head gaskets and then install them. However, i have only heard of using aluminum paint on the steel faced head gaskets which are hard to find these days. I always thought it was best to tighten the head bolts by starting at the center and then going outward in a clockwise direction.
I would recommend regular composite gaskets, such as Best Gasket, and install them dry as per manufacturer. They will bond well with the heads and block and fill minor imperfections better than copper gaskets and likely cause less corrosion with aluminum heads. I was also stumped by the speedway stud instructions regarding starting one one side of the head and working toward the other when tightening. The instructions also said to initially run the engine without coolant until the temperature reaches a point where you can't touch the heads anymore, or something to that effect. I had posted this at one time but did not really get any good answers why. Maybe this is supposed to help seal the gaskets to heads and block...
the dry starting, I could imagine doing something constructive with the gasket yes, the torqueing of the heads remains a mystery.. I think if I build up tension in very little steps, the sequence will have less importance?
IMO-sequence is very important for any type head, manifold, flange , etc., best way to ensure parts are not being "warped" or drawn together unevenly, or even cracking...as for re-torqing, it is important on aluminum as aluminum expands and contracts when heated/cooled more than cast iron, I have checked/re-torqued the heads on my flatty each year for the first few years of driving, and stopped the year after they no longer seemed to be "less than specs". But then I am known for being ****..........FWIW
ok, this is just what I thought last 15 years or so, the catch of the question, was "speedy Bill's-techtips" on the gaskets and the torqueinng. They advertise to be 'the oldest speedshop in the USA' so their knowledge on the subject should be somewhat worth following? and the we stood, gazing lamely at tips to run it dry, after torqueing the heads from one side to another, after putting aluminum heatresistant spraypaint onto your new gaskets.. I start getting the impression that this is ancient knowledge, tips from the fifties to say, OR some dodgey sceme to disable foreign flatheads :mrgreen:
http://parts.cat.com/cda/files/3035469/7/Hardware_OSS.pdf Cat Bolt catalog link, be sure that you notice that there is a black bolt (phosphate and oil coating) and a Zinc plate option in the listings different part numbers for the two options. I like the black for internal and zinc for external like Flathead head bolts and washers. Great hardware and available most countries.
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