lt1bird Posted June 16, 2010 Report Share Posted June 16, 2010 well its a 485 setup for pump gas 93 ocatane. 27cc domes checked the squish with solder...came in at .032" toward the center.... Think this will be ok? trinity setup... Thanks! Quote Link to comment Share on other sites More sharing options...
wesw Posted June 16, 2010 Report Share Posted June 16, 2010 thats pretty tight i would shoot for like .045 Quote Link to comment Share on other sites More sharing options...
sheefreak Posted June 16, 2010 Report Share Posted June 16, 2010 I agree, that is quite tight! I have run a motor at .037 before, but my builder wanted it between .035 and .042. I run my cub at .047. Quote Link to comment Share on other sites More sharing options...
mailman Posted June 16, 2010 Report Share Posted June 16, 2010 You have to be very careful with the Trinity cut domes. They don't always get the angle right on the cut. Make sure you measure the thickness of the sodder on the outside edge, inside edge, and a few in between. If the angle is off, then you will see the numbers get smaller which is a convergent squish and really can cause bad things to happen with the combustion. I wouldn't drop more than .039 or .040. Mailman Quote Link to comment Share on other sites More sharing options...
lt1bird Posted June 16, 2010 Author Report Share Posted June 16, 2010 I run .042 on my other engine. I was thinking this is way to tight. Probably beacuse the engine deck was cleaned up, removed a tad more material then I hoped for. Guess Ill get a thicker base gasket. I didnt have any way to really measure how much material was removed. Thanks! Quote Link to comment Share on other sites More sharing options...
dajogejr Posted June 16, 2010 Report Share Posted June 16, 2010 To be honest, I've heard horror stories from Trinity cut domes. Once you start playing with base gasket thickness, you're messing with port timing as well. I would actually call a reputable builder and have them cut you a set of domes based on your measurements. You could always just slap a .012 gasket on there and call it a day, but I like knowing where my motor is... Now would be a good time to take the head off and degree it in, or at least see where it's at.... Quote Link to comment Share on other sites More sharing options...
lt1bird Posted June 16, 2010 Author Report Share Posted June 16, 2010 (edited) The trinity head uses orings.... cant change that, plus like you said, changes the timing. Adding a thicker base gasket will be fine as im just replacing the material that was removed from the case deck. Right now the gasket is .039" ill see what they have around .049" and call it a day. If the case deck was stock, then I would be concerned. Is there a write up on how to check the timing? Would be interested in learning that Ive got the degree wheel etc....so just my time is needed... Thanks! Edited June 16, 2010 by lt1bird Quote Link to comment Share on other sites More sharing options...
toytech Posted June 16, 2010 Report Share Posted June 16, 2010 The trinity head uses orings.... cant change that, plus like you said, changes the timing. Adding a thicker base gasket will be fine as im just replacing the material that was removed from the case deck. Right now the gasket is .039" ill see what they have around .049" and call it a day. If the case deck was stock, then I would be concerned. Is there a write up on how to check the timing? Would be interested in learning that Ive got the degree wheel etc....so just my time is needed... Thanks! vito's performance products sells .050 and .060 base gaskets Quote Link to comment Share on other sites More sharing options...
dajogejr Posted June 16, 2010 Report Share Posted June 16, 2010 The trinity head uses orings.... cant change that, plus like you said, changes the timing. Adding a thicker base gasket will be fine as im just replacing the material that was removed from the case deck. Right now the gasket is .039" ill see what they have around .049" and call it a day. If the case deck was stock, then I would be concerned. Is there a write up on how to check the timing? Would be interested in learning that Ive got the degree wheel etc....so just my time is needed... Thanks! Fine point....I skimmed over the part where the bottom of the cylinder had a little removed...a .012 base gasket, if you can find one, in addition to what you have will put you right about where you need to be...IMO. A .020 won't hurt either... Quote Link to comment Share on other sites More sharing options...
lt1bird Posted June 16, 2010 Author Report Share Posted June 16, 2010 Boy, I would be very leary of using 2 gaskets. I would think the chance of it blowing out would be greater. Not saying it will not work but my feeling is that it would be weaker. One single gasket would clamp better... hmmm thats a tough one... im sure 2 would work. Since I need to replace the gasket anyway, may as well use one if available, 2 if I cant locate the correct one. Thanks! Quote Link to comment Share on other sites More sharing options...
Wildcardracing Posted June 16, 2010 Report Share Posted June 16, 2010 Can get you one piece base gaskets in just about any thickness you need. An other option is to make some adjustments to the domes you have. I'd do as Dave said and degree it out to see where you are; if your timings are good cut the domes, if they could be raised some go for a thicker gasket. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted June 16, 2010 Report Share Posted June 16, 2010 lt...I have used double base gaskets in the past with ZERO issues. I do use a thin RTV coats on both sides..which, honestly after you smash the gasket it actually gives you the same original thickness. I've found torqued down, you lose .001 to .002 of the thickness...you break even with RTV. Some don't believe in it...I had to sand the deck of my 4 mil cub and ran two .012 base gaskets to get the squish in check...NEVER had an issue. Quote Link to comment Share on other sites More sharing options...
lt1bird Posted June 16, 2010 Author Report Share Posted June 16, 2010 Sounds good! Thanks all for the feedback....Might hit you up for some gaskets if I need one! Quote Link to comment Share on other sites More sharing options...
WINDYCITYJOHN400 Posted June 16, 2010 Report Share Posted June 16, 2010 I'll chime in with a promise. (And I know,cause I've been there) Your Trinity domes ARE wrong. It's not your fault, so don't feel bad. But do yourself a favor and call Tim at TITAN RACING and for @ $150.00 he'll set you up with custom cut domes for your motor. "Mailman" and I, as well as a few other members here have been down this road and know that the Trinity domes are standard off the shelf domes and they don't have the proper shape to work with the pistons they use. DON'T run those domes or you'll pull your hair out fighting detonation issues that can't be solved with jetting or timing changes. Feel free to read more about it in my post in the "Product Reviews" section on this site listed under TRINITY...... P.S. your going to want .040 to .045 squish. Mine are .040. Hope that helps Quote Link to comment Share on other sites More sharing options...
lt1bird Posted June 17, 2010 Author Report Share Posted June 17, 2010 (edited) Im going to do that reasearch.... thanks for the tip. its not about money....I want it correct... See, your striking a nerve.... my 535 which only has 165PSI cranking pressure will not run on pump gas. I need 1/2 110 race gas. Even if I put the timing to stock with 93 ocatane I had detonation issues! Thanks! Edited June 17, 2010 by lt1bird Quote Link to comment Share on other sites More sharing options...
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