EvilC Posted May 26, 2013 Share Posted May 26, 2013 I figured I would post here before I went posting on LS1TECH and keep this thread updated once I come up with an answer. So my "new" setup: 5.3 Patriot heads stage 2 - bought used no specs 1.8 Terra Yella rockers stock GM 2002 LS1 head gasket Cam Specs: 228/232 111 .632/.600 So tonight I put clay on the first piston and bolted down one head onto the block and turned the engine over by hand to see how close I was getting to the piston. The clay was squashed but not broken through. It did look very close though so then I put red grease on the intake and exhaust valves and tried it again with no clay in place. There was no grease left behind by either valve on the piston. The 1.8 rockers are really my concern and I am thinking I would be safe with 1.7s. I am thinking with so much lift from the cam, once the rods stretch and higher rpms come into play, I may have an issue. Tomorrow I plan to search around on the LS1 site to find the specs on a stock 5.3 head so I can know for sure if these heads have been shaved or not. Knowing that, HG thickness, cam specs and rocker specs - I should be able to mathematically see where I am and if I have any buffer room. Quote Link to comment Share on other sites More sharing options...
Zfan1 Posted May 26, 2013 Share Posted May 26, 2013 Did you make the roller lifter solid? The hyd. roller lifter will give false readings under load or you must use a checker kit. Sorry if you already know that, you should have .060 to .080 ptv clearance to be safe. Quote Link to comment Share on other sites More sharing options...
EvilC Posted May 26, 2013 Author Share Posted May 26, 2013 (edited) zfan1 - nope I didn't know thanks for the input. So I should check the contact patch and should have 0.060 to 0.080? I think I see why this measurement will help me answer my question but also weather the contact area is towards the intake or exhaust side will tell me if the pushrod length is correct? The video I watched talked about shimming and milling the pedestals so I am trying to follow their theory. Checking the preload would also help determine is the pushrod is the incorrect length? Just watch this video Edited May 26, 2013 by EvilC Quote Link to comment Share on other sites More sharing options...
rsicard Posted May 26, 2013 Share Posted May 26, 2013 The Video is VERY good and effective marketing. What is omitted is the facts on the design. Aluminum has a habit of fatiguing and snapping into pieces. Steel or Stainless Steel is MUCH stronger and will last nearly indefinitely. I put stainless steel shaft rockers on my 383 stroker. Now it occurred to me that I don't know where the oil goes after coming up the pushrod. There is no oiling of the trunion nor the valve springs! I am getting rid of the shaft rockers and going to stud mounted roller rockers along with a stud girdle that have oiling to the rocker trunion and to the valve spring. If the valve spring oiling is insufficient, then I will fab a oil spray bar in the cylinder head. Spraying oil on the valve springs keeps them cooler and lasting longer. Quote Link to comment Share on other sites More sharing options...
SUNNY Z Posted May 26, 2013 Share Posted May 26, 2013 Do it right and use a dial indicator. Quote Link to comment Share on other sites More sharing options...
blueshark123 Posted June 13, 2013 Share Posted June 13, 2013 Is there a specific reason you went 1.8? Do you know if the cam is ground for 1.8? Quote Link to comment Share on other sites More sharing options...
Zfan1 Posted June 13, 2013 Share Posted June 13, 2013 To raise the lift if the cam he got is lacking in the lift department. Agree'd, steel rockers are a much better choice, less fatigue and breakage plus if you go with real a real big cam and stiff springs it's the only choice unless you like buying expensive LS motors! Quote Link to comment Share on other sites More sharing options...
EvilC Posted June 13, 2013 Author Share Posted June 13, 2013 The 1.8s came with the used heads I bought - I am going to sell them and get 1.7s. Quote Link to comment Share on other sites More sharing options...
Nexgen1llc Posted June 25, 2013 Share Posted June 25, 2013 Check your clearance with no head gasket in place: bolt the head on (lightly tight bolts not torqued), turn it 360 degrees(with clay). use a solid lifter lashed @ .012" (same spec as where a hydraulic runs at) If it spins over with no interference, obtain compressed thickness spec of the head gasket you're planning to use and add the measurement (clearance ) to the thinnest clearance on the piston crown. If you have .070" or more...you're safe. Don't run the 1.8's Quote Link to comment Share on other sites More sharing options...
EvilC Posted June 25, 2013 Author Share Posted June 25, 2013 Thanks Nexgen - I have the 1.8s up for sale, they will not work for me. Quote Link to comment Share on other sites More sharing options...
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