WL High Compression Heads

[RvP]

I originally had this posted in the engine rebuilding forum and got no replies:

While I am sorting out my cylinder problems I was wondering about putting on the high compression heads. My WLA has the #5 heads and depending where you read, the #5 heads are good for 22 horsepower. What is the expected horsepower with the high compression heads? Any draw backs to using them such as head/valve clearance problems? Overheating?

[Paps]

If you are concerned with correctness, stay with the low compression. The repop highs, at least the ones Kurt, at Flatland Motorcycle Company sells, goes, are excellent quality and they have been cc'd equal, several times buy customers. HP ??? You don't gain much on it. After all, high comp 45 heads are still low comp, when it comes to kicker her over. Want real increased HP ? Change cams. etc. etc.... You will still need the higher comp heads to boot. Paps

[RvP]

High Compression Heads

Thanks for the advice. I am not worried about correctness, the WLA motor is in a civilian frame. I was looking for a "bolt on" power increase since I ride 2 up a lot. Heads I can do, shimming cams I am not skilled enough to do (yet).

My curiosity is still nagging me, what's your best guess on horsepower for the WLA engine with #5 (medium compression) heads and with the #6 high compression heads? I have read 2 different hp ratings for the #5, 22 or 25, depending on the source. I have never read any horsepower rating for the #6. My original riders handbook has one general statement for the WLD & WLDR (all high compression), W & WL & G (all mediumm compression) that the "average developed power and RPM - 25 HP at 4600 RPM". They can't all be the same, especailly putting the medium compression G in the same horsepower rating as the WLDR. What's your best guess?

[Paps]

26 on the high and it depends on the fuel. You can gain quite of bit extra [roughly 10hp] with a stroker kit, high comp heads, wldr cams, gearing, and mikuni or cv carb. Kurt can fix you up with all of these parts and data. Tell him...I luv pestering him Paps

[RvP]

Thanks!

Paps, I did pass your message on with an Email to Kurt at 45 Part Depot. Kurt answered right away (as always) and had great information. Thanks.

[Paps]

Glad to hear Kurt was able to help you out. Paps