www.CVOHARLEY.com

CVO Technical => Twin Cam => Topic started by: Street Stalker on August 03, 2006, 11:04:01 AM

Title: Can I install pro 103 high compression pistons?
Post by: Street Stalker on August 03, 2006, 11:04:01 AM
Guys,

Was wondering if I could install pro 103 10.5-1 pistons in my 06 S.E. Fatboy?
Title: Re: Can I install pro 103 high compression pistons
Post by: AUSSIE_FLSTFSE on August 03, 2006, 03:52:35 PM
You will have to change cams again & would also be pointless with out changing to 103+ or HTCC heads!

Cheers
Aussie
Title: Re: Can I install pro 103 high compression pistons
Post by: DCFIREMANN on August 03, 2006, 05:55:46 PM
Quote
You will have to change cams again & would also be pointless with out changing to 103+ or HTCC heads!

Cheers
Aussie

ZIPPERS will need to redo your heads. They do not run the 575 cams with the high compression pistons, they will want you to run either the red shift tc 647 or the tc 657.

Be Safe

THE DAWG
Title: Re: Can I install pro 103 high compression pistons
Post by: ajh on August 03, 2006, 07:11:15 PM
Scott,
Adam here from Zipper's & Red Shift Cams. Just wanted to clarify a few things on this subject. I apologize that you were told the incorrect information, the Muscle 103 Kit is being sold with the 657 Red Shift Cams. The 575 was specifically developed for a stock 103 configuration. If you check your cranking compression, you should be at 180 with your current configuration. We documented 180 on both cylinders on DCFireman's bike when it was configured as a 103.

If you try to use a high compression piston with these cams, your cranking compression could elevate above 200 which would not be a good situation. You will have a very hard time getting rid of the pinging and could cause fatal problems to arise. I worked directly on the development of the 575 and can guarantee that it was meant for stock compression engine.

I am unfamiliar with the pro-103 high compression piston, so I do not know the jump in compression that is expected with the piston. If you are the adventurous type and want to see what happens, I would certainly check the cranking compression before attempting to run or tune the motorcycle, however I would research other options for gaining power and retaining the 575's. A larger throttle body or ceramic heat coatings on the top of your piston, combustion chamber, valves, and ports would give you an edge over your current setup.

Zipper's is currently setup at Sturigs doing ThunderMax installations, so the shop is pretty empty this week and next. If you have any other questions please feel free to contact me, however please note that I not be back in the shop until Monday the 8th.

Thanks and I hope the 575's are working well for you,
Adam Herbert
Mechanical Engineer
Red Shift Cams / Zipper's Performance Products
Title: Re: Can I install pro 103 high compression pistons
Post by: Fired00d on August 03, 2006, 07:27:38 PM
Quote
......Thanks and I hope the 575's are working well for you,
Adam Herbert
Mechanical Engineer
Red Shift Cams / Zipper's Performance Products
They are working so well, and make my scooter so much fun to ride I feel as I owe you several [smiley=drink.gif] [smiley=drink.gif] Thanks

 [smiley=pumpkin.gif]
Ride Safe,
Fired00d
 [smiley=fireman.gif]
Title: Re: Can I install pro 103 high compression pistons
Post by: Unbalanced on August 03, 2006, 09:23:16 PM
If your looking for more power, send your heads off to Zippers, cometic .030 gasket, Bassani Road Rage 2 into 1, 657 Cams, Fueling / Jim's roller rockers, check clearance on the rockerboxes, Zippers Push Rods a bit stiffer and a tiny bit more work to get them in as it is a tighter fit over the SE adjustables, Fueling oil pump, Zippers Schim and a tune.

Also if you have the 43mm throttle body send it off to Wes Brown at Cycle Rama and have them bore it out to a 48mm.

The bike should really get up and roll.   This was almost exactly the test I ran for the Zippers Muscle Heads on the bike that was totalled recently.

In this test we also ran the forged SE 10.5 to 1 Pistons with Compression Releases.  Overall the bike was about 10.2 or 10.3 to one and we had also thermal coated the heads, and the pistons,valves etc.

Any questions PM me,

-harry
Title: Re: Can I install pro 103 high compression pistons
Post by: Street Stalker on August 04, 2006, 09:05:54 AM
Excellent, thanks for the responses.  Guess the high comp. pistons are'nt the answer without changing cams.  Thanks Zippers for clarifying the muscle kit and compression numbers.

Scott