Waz up Doc,

Sorry, couldn't resist. Could you tell me more about your 225-260 stroker engine crank. I'm rebuilding/restoring my 65 Dart conv. and would love to build a fun slant stroker that is still cruisable. What kind of welding/ grinding did you have done to the crank to get the extra throw and is this something I could have done in the Seattle area? Would the extra throw prevent installing a windage tray? Lastly did you ever figure out what kind of hp your 260 slant produced. Thanks for all the cool info Doc.

-Keep on Slantin'

Ned


ELange@mellon.uscg.mil

Doing a welded stroker crank is a lot of work and it is expensive. Here are the steps:

Select a good crank "core". Clean, magnaflux, check for bad threads, bent snout or rear flange. Use a 68-76 forged steel / big hub unit.

Deburr / weight reduce / smooth-out all the rough edges, you will have to rebalance the unit so take-off all the rough edges.

Weld build-up along the outside edges of the crank pin, some have low walls. (not all) Doing this keeps oil from escaping do to excess side clearance.

Find a good crank shop with a "submerged arc" wire feed crank welding machine. Call around and get some quotes. First tell them you have a crank that needs some journals welded and reground. Good shops will quote something like: "$50.00 for the first journal then $30.00 each after that, then $100.00 to regrind to size." (They will start to "backpeddle" when you tell them you want all 6 journals welded)

The last SL6 stroker crank I did got nitride hardened. (another $80.00) This also helps stress relieve the crank. If you plan to do this, tell the grinder to leave all journals .0005 big to leave material for a final polish after nitride.

Last step is the rebalance, one crank I did was not far off and only cost $80.00 to rebalance, the other needed more work and was double that cost.

Max stroke with no block grinding is appx 4.4
I have successfully done 4.5 stroke but it takes a good amount of block grinding and 12 point con rod nuts. (ARP)

Expect to spend between $600 & &1000.00 for all this and you will be doing a few "trial assemblies" to get everything right. You will have to do some math to make sure the compression ends-up where you want it.

Although the 260 I have in my 66 Dart is strong at low speeds, it still has a stock cam and 1 bbl carb so it really does not produce that much more HP then a stock 225, it does feel and "pull" a lot harder then a 225 from 1000 to 3000 RPM. The compression on the engine is 7.9 to 1 so a Turbo would be a great next step.
DD