Refresh951's Hybrid Ultra Stroker Build
#136
Race Car
I would measure where the worst runout is and polish that journal down a little. A little extra oil clearance on one or two main journals isn't going to hurt anything. However, wiping all the oil away with not enough clearance can.
#137
Rennlist Member
I know these bigger bore motors will have more torque but 6400 seems a tad low, no?
#138
Rennlist Member
Thread Starter
I really see no reason to go higher. I have looked at a lot of dyno sheets and it seems most motors do not make much more power above 6000 rpm. Top speed would be the only reason I could see going higher. Going higher without a dry sump also seems like it is asking for trouble especially if oil cavitation is a factor in the inherent bearing weakness in our motors.
Last edited by refresh951; 01-27-2013 at 09:31 AM.
#139
Rennlist Member
Thread Starter
Completed the short block this weekend. I am amazed how long it takes to put the short block together. Very time consuming process that requires a great deal of patience. Pretty happy with the results. Everything looks good. Going to try to get the long block completed by next weekend and then start on the turbo/exhaust fab work.
951 Pully (left) and the S2 Harmonic Balancer (right)
951 Pully (left) and the S2 Harmonic Balancer (right)
#140
Rennlist Member
Thanks Sid. This was my approach. Short block is assembled.
I really see no reason to go higher. I have looked at a lot of dyno sheets and it seems most motors do not make much more power above 6000 rpm. Top speed would be the only reason I could see going higher. Going higher without a dry sump also seems like it is asking for trouble especially if oil cavitation is a factor in the inherent bearing weakness in our motors.
I really see no reason to go higher. I have looked at a lot of dyno sheets and it seems most motors do not make much more power above 6000 rpm. Top speed would be the only reason I could see going higher. Going higher without a dry sump also seems like it is asking for trouble especially if oil cavitation is a factor in the inherent bearing weakness in our motors.
#141
Rennlist Member
Thread Starter
944 / 924S
Intake opens: 1¡ after TDC
Intake closes: 49¡ after BDC
Exhaust opens: 47¡ before BDC
Exhaust closes: 1¡ after TDC
944 Turbo
Intake opens: 1¡ after TDC
Intake closes: 49¡ after BDC
Exhaust opens: 43¡ before BDC
Exhaust closes: 3¡ before TDC
#143
Three Wheelin'
Wow.. I wish i was this far in my project.. The bushes still have to be ordered and the pistons have to be made.. And you are already building! I'm jealous!
#144
Race Car
The beauty of "off the shelf" parts. Along with having a trusted machinist to work with. Other than the block sleeving, these can be done in a couple weeks.
I'm glad Shawn ran with it so quickly
#145
Rennlist Member
Thread Starter
#146
Less HP at low rpm and slower spool up?
#147
Rennlist Member
Thread Starter
"Clayed" the valves tonight. Build is a non-interference design. I appreciate Sid's input about running a bit down in the hole and going with a smaller inverted dome. The exhaust valves have about 0.05" clearance between the bottom of the exhaust valve and the piston. These measurements were with the OEM Turbo cam and no cam tower gasket. With the Late NA cam (additional 0.039" lift) it will be VERY tight. Also, if you go with an intake valve any bigger than 47 mm (+2) it will not clear the valve relief.
#150
Race Car
Looks like its coming together well. It will be close if the belt breaks, but let's hope it never gets tested. Looks like my next cam won't be non interference on the bigger engine .
I'm getting excited just watching your progress.
I did find some longer rods for your next build ... Lol
I'm thinking a 3.6 liter monster hybrid
I'm getting excited just watching your progress.
I did find some longer rods for your next build ... Lol
I'm thinking a 3.6 liter monster hybrid