alcoholbanshee Posted December 29, 2008 Report Share Posted December 29, 2008 Measure the stroke.........It will be either 54mm or 58mm depending on what crank you have. That is where you need to start. I am wondering if the builder set these cylinders up to run with no base gasket. What is the thickness of the base gasket you are using. Quote Link to comment Share on other sites More sharing options...
Sheesbest Posted December 29, 2008 Author Report Share Posted December 29, 2008 Stroke 54mm and the base gasket stock. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted December 29, 2008 Report Share Posted December 29, 2008 It looks like it has a positive deck height by that picture. Stock base gaskets are .012...I think, but I'm not positive. Try using two base gaskets...or, get a thicker set. Gonna have to measure what you have first. Don't worry about running double base gaskets, I've done it no problem. I think someone decked those cylinders.. Quote Link to comment Share on other sites More sharing options...
alcoholbanshee Posted December 29, 2008 Report Share Posted December 29, 2008 It looks like it has a positive deck height by that picture.Stock base gaskets are .012...I think, but I'm not positive. Try using two base gaskets...or, get a thicker set. Gonna have to measure what you have first. Don't worry about running double base gaskets, I've done it no problem. I think someone decked those cylinders.. But if he is hitting the head with the piston with 1 base gasket....then 2 gaskets (assuming that they are indeed .012),the squish would still only be a maximum of .012. And we all know that is just a little bit tight....LOL!!! Not sure what the answer is here...............Now using the spacer plate with a stock base gasket you could not squish 2mm solder. 2mm = .078, so even if you took away the 1 base gasket you would still have greater than .066 squish. So in my opinion the base gasket is a dead end road. I guess my suggestion would be to get a measurement of the piston to deck at top dead center and pass that info on to a builder to have them cut a set of domes for his specific application. Another thing I would consider is degreeing this engine to see if it is worth wasting time on a set of cylinders that may or may not run like poo. There is obviously some issues with these cylinders.......LOL Quote Link to comment Share on other sites More sharing options...
dajogejr Posted December 29, 2008 Report Share Posted December 29, 2008 True that... I'd like to know the thickness of the new and compressed base gaskets he's using for starters... Same could be said for a .020 base...if it's hitting with that, .020 squish ain't gonna cut it either. Thanks for the backup homie... Quote Link to comment Share on other sites More sharing options...
alcoholbanshee Posted December 29, 2008 Report Share Posted December 29, 2008 True that...I'd like to know the thickness of the new and compressed base gaskets he's using for starters... Same could be said for a .020 base...if it's hitting with that, .020 squish ain't gonna cut it either. Thanks for the backup homie... I think custom domes are about the best option. But with that said the engine should be degreed to see if it is worth even spending time/ money on. It would be nice to know where the port timings are at, allthough most dont have the equipment to measure that....lol Quote Link to comment Share on other sites More sharing options...
Sheesbest Posted December 29, 2008 Author Report Share Posted December 29, 2008 These cylinders might have been decked before I dont know. Why did I not have this problem with the stock crank and pistons. I thought that the 795 pistons made up for the 5mm longer rod. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted December 29, 2008 Report Share Posted December 29, 2008 On your old setup, was there a spacer plate? Did you measure your old base gasket (a squashed piece of it), could you get numbers off your old one? Are you 100% certain you have stock stroke long rod crank in there? Quote Link to comment Share on other sites More sharing options...
Sheesbest Posted December 29, 2008 Author Report Share Posted December 29, 2008 I checked the stroke when Alcoholbanshee asked and it measured 54mm. No spacer plate on the stock setup. Did not take notice of the old base gasket before sending it in. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted December 29, 2008 Report Share Posted December 29, 2008 Someone should be able to measure a stock set of cylinders for you...I can't. I know this is a stretch...but do you remember if the old bask gasket was real, real think (like 3-4 times the thickness of a stocker)..?? If the rods are 115, the crank is a stock stroke...there are only a few things it can be. Bad pistons (very, highly unlikely...), wrong rods (also highly unlikely) or a cut/modified cylinder you weren't aware of before it was sent out. Something doesn't add up.... Quote Link to comment Share on other sites More sharing options...
Sheesbest Posted December 29, 2008 Author Report Share Posted December 29, 2008 Can only be a cylinder problem not rods or pistons. Do you think the base gasket thickness should increase to compensate for the problem or should I have the domes cut. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted December 29, 2008 Report Share Posted December 29, 2008 Can only be a cylinder problem not rods or pistons. Do you think the base gasket thickness should increaseto compensate for the problem or should I have the domes cut. that's where a degree wheel comes into play. To see where the timing is at. Once that's set...you figure out if you need to stuff more gasket under, or get domes cut. Quote Link to comment Share on other sites More sharing options...
sheerider1026 Posted December 29, 2008 Report Share Posted December 29, 2008 you sure its not a 4mm crank??? soemone would have had to cut a lot of metal of the cylinder decks for it to look like that Quote Link to comment Share on other sites More sharing options...
Sheesbest Posted December 30, 2008 Author Report Share Posted December 30, 2008 you sure its not a 4mm crank??? soemone would have had to cut a lot of metal of the cylinder decks for it to look like that I think that if it was a 4mm crank the squish would have been less than 2mm. Quote Link to comment Share on other sites More sharing options...
firebanshee Posted December 30, 2008 Report Share Posted December 30, 2008 I think that if it was a 4mm crank the squish would have been less than 2mm. Are you sure you got the solder ALL the way over to the edge of the cylinder and not just in the bowl area? Quote Link to comment Share on other sites More sharing options...
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