Underdog88
New member
Looks like I've lost a second season of boating
unless I'm missing somthing. Please tell me I am... Last year missed due to business but built two fresh short blocks and rerigged the boat this winter/spring.
I have/had 2 sets of Merlin Ovals to work on. Just wanted to gasket match and pocket port them. One set appeared to have been milled down before I got them used. I sent them to a friends machine shop to surface those and take a bit off of the other set to try and match them up. It took him forever but he was doing it for free as a favor so....
He told me he had a problem and cut one head crooked so he had to cut more to straighten it up. Then he cut the same amount from the other 3.
When I finally got them back I freaked out... He had cut well down into the intake seats
They were 119cc chambers and my pistons are only 10.5cc domes so I figured more compression wouldn't be a problem.
Being the optimist I am, I continued to work on them. I sank the intake valves enuff to get the seats back, after spending a ton of time on the ports and combustion chambers, replaced a few valves, shimmed the springs and slapped them on the motors. Valve to piston clearance wasn't there and roller rockers not centered on stems at all. Pulled em back off and did what I should have done as soon as I got them back from the shop. Put light springs on a couple valves and check piston to valve. Exhaust ok but intake hitting badly. I had to back off the rocker screws to a point where I ended up w/about 1/8" slop at the stem off lobe to clear pistons. Heavy sigh... Running only 540 lift flat tap cams.
I've drove myself crazy trying to make them work but I cant see it. .100 Thick head gaskets will drop compression to nothing, I don't think I can cut that much off piston pocket as the top feels only 1/4" thick or less. Plus I've paid a good race shop to assemble the short blocks after resizing rods w/new bolts ect... One head has much more off than the other. The intakes only show half a bolt hole w/out gaskets. The other not as bad until gsk are installed. I know I can cut the intake side of the heads but think it will hit the block rails then as well. I've crudely cc'd the comb chambers and one set is way down to @90cc and the others about 110. Blocks done at different times and one is Zero decked and the other -.030 so I'd hoped to compensate there.
I retarded cam 4* just to try and it helped a bit but not enough.
Am I missing anything??? Or do I have 4k worth of boat anchors... New Merlins are 2k per set. I've seen ProComp Aluminum for 1k plus swapping out exhaust valves to inconell. I know they are chineese castings but when assembles with good componets by a good head man they are ok I'm told. That's still 2k I don't have right now.
Any suggestions? Am I missing any way to save these things?
Thanks so much for your time and knowlege in advance.
Mark(who was expecting to be on my way to Loto this week)Underwood
Maybe next year...
unless I'm missing somthing. Please tell me I am... Last year missed due to business but built two fresh short blocks and rerigged the boat this winter/spring.I have/had 2 sets of Merlin Ovals to work on. Just wanted to gasket match and pocket port them. One set appeared to have been milled down before I got them used. I sent them to a friends machine shop to surface those and take a bit off of the other set to try and match them up. It took him forever but he was doing it for free as a favor so....
He told me he had a problem and cut one head crooked so he had to cut more to straighten it up. Then he cut the same amount from the other 3.
When I finally got them back I freaked out... He had cut well down into the intake seats
They were 119cc chambers and my pistons are only 10.5cc domes so I figured more compression wouldn't be a problem.Being the optimist I am, I continued to work on them. I sank the intake valves enuff to get the seats back, after spending a ton of time on the ports and combustion chambers, replaced a few valves, shimmed the springs and slapped them on the motors. Valve to piston clearance wasn't there and roller rockers not centered on stems at all. Pulled em back off and did what I should have done as soon as I got them back from the shop. Put light springs on a couple valves and check piston to valve. Exhaust ok but intake hitting badly. I had to back off the rocker screws to a point where I ended up w/about 1/8" slop at the stem off lobe to clear pistons. Heavy sigh... Running only 540 lift flat tap cams.
I've drove myself crazy trying to make them work but I cant see it. .100 Thick head gaskets will drop compression to nothing, I don't think I can cut that much off piston pocket as the top feels only 1/4" thick or less. Plus I've paid a good race shop to assemble the short blocks after resizing rods w/new bolts ect... One head has much more off than the other. The intakes only show half a bolt hole w/out gaskets. The other not as bad until gsk are installed. I know I can cut the intake side of the heads but think it will hit the block rails then as well. I've crudely cc'd the comb chambers and one set is way down to @90cc and the others about 110. Blocks done at different times and one is Zero decked and the other -.030 so I'd hoped to compensate there.
I retarded cam 4* just to try and it helped a bit but not enough.
Am I missing anything??? Or do I have 4k worth of boat anchors... New Merlins are 2k per set. I've seen ProComp Aluminum for 1k plus swapping out exhaust valves to inconell. I know they are chineese castings but when assembles with good componets by a good head man they are ok I'm told. That's still 2k I don't have right now.
Any suggestions? Am I missing any way to save these things?
Thanks so much for your time and knowlege in advance.
Mark(who was expecting to be on my way to Loto this week)Underwood
Maybe next year...
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