supermx96

Yes that is what i am planing, i will probably going with JE this time.

What ring set material is best for blower application?

MER Performance

Did I miss something? I just read this is forced induction. Don't take this the wrong way, but who advised you to use Speed Pro piston? The Speed Pro piston and the blower is the reason the ring lang is burnt away. No less than a .200 wall wrist pin, blower piston a must the ring lang stack must have enough material between rings to prevent the ring side clearance from tightening up. Forward offset carb plate, am I understanding a single carb, towards the front? If thats the the set-up, I can see why you have problems.
Rings: Hell Fire top, Napier 2nd, low tension oil. # 525 stone on finish hone, platue hone. .0055 x bore top gap, second gap .004-.008 larger than top. This pervents gas build-up between 1st and second rings, which causes ring flutter.

supermx96

Nobody advise me to use Speed Pro piston, this engine was my first bbc rebuilt I have always do my engine on snowmobile or my motocross bike but i know thats is all different story between them.

So the engine was a merc 525sc gen 6 before the rebuilt and the stock merc 525sc have trw piston in them, So thats is the reason i have rebuilt the engine with the same piston (trw=speed pro) now i know that i have make an error there, during the summer it was already a winter project to change that piston for JE piston.

I make my experiance and i know i will pay for that...

Thanks for ring recomandation.

supermx96

What about total seal gapless ring on marine blower engine application??

FIXX

iTrader: (2)

that's the ticket on the rings you want to use..umm last i checked merc used j&e on all their blower engines,,someone may have changed them b4 you got the engine..

FIXX

iTrader: (2)

the forewars off set carb plate is a better design,,it keeps the front cylinders from starving for fuel..

supermx96

take a look in merc HP #3 hi- perf manual the 525sc come with TRW piston from factory all others have JE.

supermx96

I have read this when i built the engine but on my setup it make the rear cylinder leaner than the front.

Another thing that i have note is that the blower rotors have come black at the rear end until the midle of the rotor, i supose that it is a sing of lack of fuel lubrification at the rear posibly because the fuel burn or evaporate in blower before coming into engine???
That blower setup (single offset carb) make big heat at 9lbs at the rear end.
I have been able to clean the rotors with fuel.

FIXX

iTrader: (2)

you have too much boost for that blower,,all your boing is destroying everything you throw at it..your better off raising the compression and running a bigger pulley..