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If I use a 74 mm crank and CB unitec rods in an AS41 DR case, will I have to do any grinding the cam for clearance? If those rods won't clear are there any recomendations for some that will?

Thanks

Well frankly you are the best person to determine that, myself I would be surprised if that stroke with any rod was an issue.

the reason I ask is I haven't purchase any parts for the motor build yet. Still deciding on the specifics of the build. I'm really trying to shy away from any clearance issues. So with that being said, I will defiantly consider a 74 crank if there is no clearance needed crank/cam or case. Thanks for your advice!

I never said anything about the case, sometimes but it is rare a stock crank may not even fit a stock case.

Build the engine you want, don't try to compromise by thinking easy.

I was mainly intersted in the cam clearance. I mentioned the case in my response because I have read a number of threads and articals that state most of the time a 74 crank wiil drop in without any problems.

My plan is to build a mild stroker using the 74 crank and 90.5 pistions. Don't need a whole lot of performance just a good comprimise between a stocker and a hot rod.

Thanks for your advice! By the way, what part of Oregon are you from. I ask cause I'm considering relocating to Oregon when I retire, along the coast.

Thanks again

You're not guaranteed from clearance issues with anything. Clearancing a cam is no harder than tapping an oil galley or setting deck height. I wouldn't suggest picking engine components because you want them to "drop in". Decide how much power you want, look at your budget and buy the best parts that get you there. There are a ton of people here that can help you make it work right.

Have your case machined for a stroker crank and build a real engine.

Don't compromise.

a 74 should not come anywhere near the cam, even with stock rods.
Probably not even a 78.

Nothing is guaranteed no matter what the combo.

I'm in the rogue valley, that would be the southern part of the state along the I5 corridor.

Thanks for the help here guys. I'm going to give the build some more though before I make any moves (figure out what I really want).

What do you guys think about using a used case for a build of this type. I have an as41 DR, align bored to 20 over, the thrust is in good shape and no signs of any cracks. Would I be better off buying a new case (I'm kinda thinking thats the way to go)?

Thanks for all the help guys.

if the case you have looks to be in good shape go ahead and use it.
( more $ for other stuff )

you should'nt have any clearance isues with a 74mm crank, if any it would just be minor. nothing a die grinder could'nt handle in a few minutes. its not that big a deal.

My 82mm stroke crank with VW stroker rods did not require cam clearancing. 76 mm crank and Scat I beam rods also fit most cases with out clearancing. It takes about ten minutes with a die grinder to clearance a cam.

you will not need a clearanced camshaft, it will fit fine .
just built one same combo yesterday .

You can also get cams that are already clearanced. I buy Scat SC-1 blanks and have them ground. Tim