I am looking to rebuild my DS 650 motor and make a little more horsepower. I have a few questions.

1. If I went with a Ron Woods stage 1, should I be worried about not having a rev limiter with the stock valve springs.

2. What is the difference between the Ron Woods dual valve springs and a shim under kit in terms of being able to increase the rev limit. I would like to increase the rev limit to 9500rpm.

3. What kind of horsepower would I expect out of a Ron Woods stage II?

 

Okay, let's ask this another way. I am planning a rebuild and am wondering what parts I need to achieve: 56-60hp, 9000-9500rpm rev limit, and reasonable reliability as it will be run in endurance events. My thoughts are 11.5-12:1 compression piston (don't want to run straight race gas and higher compression not good for top end), carb (leaning towards lectron 46hv as will be run at higher rpm's), pipe (Top Gun or Ron Woods), stainless valves, intake porting, cam's such as hpr2's or 3's (or equivalent Woods cams), and an MSD ignition (due to it's adjustability). Is it worth the extra money to go to the shim under kit opposed to heavy duty springs to ensure that the valves won't float? A Ron Woods stage II kit would accomplish most of what I am after, but I would rather have the rev limit adjustability of the MSD ignition and the higher top end of the Lectron. I am only expecting 50-60 hours between total rebuilds as this motor will be run hard.

 

How much are you planning on spending? You said you were doing stainless valves, but if your going that far I think I would look into a big valve setup, and more porting. HPR, The Bom, KMS, and TVI all do porting so you are not locked in the Woods porting unless you are sold on the work they are doing. I would deffinetly be worried about the stock valve springs and the no rev limit Woods CDI. From everything I have heard the shim under kit is the way to go. It's not much to pay for a little more assurance that you have the best possible setup... if anything happened you would know you had done every thing possible. I would look into a different CDI if it was me... IMO there is more to be lost (broken parts) with the no rev limit than to be gained. Besides unless you are getting crazy with radical cams and planning on reving to the moon all the time, there is no need to rev that high. Look into the Big Gun for the lowest price option, or the Vortex if you want to get spendy. I've heard that the MSD ignition is cool but very bulky and you have to cut the harness and cannot put the stocker back on unless you splice back on the OEM connecter. I like the 46HV but if you have any plans to do more you might as well get the 48HV. I like you pipe choices I would also have a look at the Big Gin pipe... my buddy has it on his DS and it feels real solid. Good Luck!

 

Give Eric a call at HPR, great guy with great advice... He will tell you what you need, not what he wants to sell. I talked to him and he talked me out of doing a stroker kit for my application because it's not necessary.
HPR's Website