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2002 800 summit Pistons?

T
Apr 17, 2009
57
4
8
Glasgow, MT
I took the head off of my 800 last night to measure and order pistons and rings. I baught the sled used and didn't know wether it was stock or not. I'm new at this so could use some help. First of all the compresion was 94 and 112. When I pulled the head the top of the pistons seemed to have enough soggy ash to write your name in. My questions at this time are that the cylinders show some wear marks or color variations but are smooth as a babys but to the touch, are these ok. Next , the sled has only had amsoil racing oil used, that build up on the pistons seems awful rich, shouldn't it be brown and hard? Does it matter also if the plug wires somehow were switched opposite. Now, what piston kit should I get coming. I'm pretty open, rk teck, spi molly, weseco? The sled measured to be stock 82mm.
 

Summit8

Well-known member
Premium Member
Oct 13, 2001
936
63
28
63
Fairview, MT
I was running wiseco 2-ring pistons with no problems before my crank bearings took a dump 3 years ago, then sent my motor off to BigJohn to have a new crank installed and his 840 HO kit installed. I lost a piston and cyl. the last 2 seasons and the second time he admitted the 84mm Wiseco pistons he was using did not hold up, explaining I think why I lost 2 cyls. and pistons when my egt's where plumb fine and good gas was used, plug/piston color and wash looked right on also.
As of this summer both Sled Head Racing and RKT changed piston supplier to a German built piston which both them and I, hope solves the problem. Sounds like this was just with BJ's 840 kits, don't know about Kelsey's 827 piston history.

My .02 FWIW, not bashing.:beer;:)
 
T

Tackbtch

ACCOUNT CLOSED
Nov 12, 2004
951
25
28
Trout Creek MT
Well I dont know about the ash deal? I ve run nothing but Castrol HP snowmobile oil in my doos with no problem. I changed out my stock pistons for the doulbe ring piston kit from MCB. Have had good luck so far but dont have but 500 miles on the first sled and only 20 miles on the second sled. I did the drop in kit from RKT on my 02 ...reflash the mpem and got the cheater head. Worked great. I would say to doo some research, install a set of doulbe ring pistons of your choice and enjoy. Dino
 
E

Elkwagn

Member
Dec 18, 2007
133
5
18
53
Boulder Mt
I had the same thing happen to my 02, skirt came right off one piston but luckily didnt hurt case or cylinder. Question is where do I get a set of these SPI pistons you are talking about?
 
S

sledsrock

Well-known member
Nov 26, 2007
1,826
510
113
Grand Junction, Co.
I had the same thing happen to my 02, skirt came right off one piston but luckily didnt hurt case or cylinder. Question is where do I get a set of these SPI pistons you are talking about?


I was able to get SPI's through my Doo dealer. Be sure and get the "T" Moly series, they are a better piston.
 
I had the same thing happen to my 02, skirt came right off one piston but luckily didnt hurt case or cylinder. Question is where do I get a set of these SPI pistons you are talking about?

X2 on the Doo dealer here in B.C. I bought mine cheaper through Royal Distributing - they are labelled as SPX but the exact same as an SPI piston. When Gamma Sports distributes them to Royal - they rebadge them as SPX.
Hope this helps......
 
T
Apr 17, 2009
57
4
8
Glasgow, MT
summit pistons

Thanx guys, I ordered the 2 ring piston and gasket kit from MCB Performance. Waiting for parts to arrive. I still haven't found out on the 02 800 Summit if the plugwires are specific to each plug or do they both fire @ 180 deg from each other. If I switched the wires around it seemed to start and run the same. Maybe after the topp end kit is installed it will be diff.
 
B
Dec 4, 2007
36
5
8
Good choice on the mcb at least they are 2 rings vs spi were one!!!
x4 on wisceos ring locator pin receeded on mine and spun ring wrecked head cylnder rave valve and jug 600 miles on them thats was it
spark plug wires no it does not matter for the coil fires both at the same time
 

Summit8

Well-known member
Premium Member
Oct 13, 2001
936
63
28
63
Fairview, MT
You see the SPI piston sets on ebay alot, lots of old stock around apparently. Bought ready to find me a set of stock jugs and a set of these pistons myself.
LOL, I must be the only guy out there that got lucky with a set of WISECO pistons.:beer;:D. I capitalized the name so you guys can learn how to spell it also.;)
 
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