loftygoals Posted January 14, 2011 Share Posted January 14, 2011 I've just bolted my new head on. It was decked to near minimum uninstalled spec. I used a standard 1.1mm head gasket. I know where to measure, but it is very difficult to get a micrometer in there. Is the a specific type or brand that is preferred for taking the measurement? With my micrometer it looks like I'm good by a .15-.2 mm. We'll have to see what happens after some heat cycles. I still need to install the timing belt and see if I can even use a setup at the minimums on an early block. I'll let everyone know how it works out. -bj Quote Link to comment Share on other sites More sharing options...
cbuzz Posted January 14, 2011 Share Posted January 14, 2011 I measured mine with the intake boot removed. I tried to upload pic but site won't let me. Keep us posted. Quote Link to comment Share on other sites More sharing options...
loftygoals Posted January 14, 2011 Author Share Posted January 14, 2011 I measured mine with the intake boot removed. I have the intake completely off the car. It is just a bare head at the moment. The water pump is getting in my way. The water pump rises slightly above the block. -bj Quote Link to comment Share on other sites More sharing options...
loftygoals Posted January 15, 2011 Author Share Posted January 15, 2011 Well, timing belt is installed. I had no problem getting appropriate tension with an early block. It looks like timing is slightly retarded as expected. This is with the crank at TDC: What do you you guys think? Here are the risks: The thin head reduces clearance between the piston and valves Retarded timing further reduces the distance between the exhaust valves and pistons Even a degree retarded will move the power band higher RPMs. OK, what am I missing? Any predictions on if it'll run right? I'm hoping to have the car back together late tonight. -bj Quote Link to comment Share on other sites More sharing options...
Sterling Doc Posted January 15, 2011 Share Posted January 15, 2011 Great pics, and interesting build.Interesting to see what happens with a min thickness head! I predict it will run well, but: 1) Don't let it overheat! 2) Don't miss any shifts! Quote Link to comment Share on other sites More sharing options...
loftygoals Posted January 15, 2011 Author Share Posted January 15, 2011 Great pics, and interesting build.Interesting to see what happens with a min thickness head! It will be interesting to see this combination of parts, too: Late head, cam, headers & very early block, forged cross drilled crank, 9.5:1 pistons, electronics (injectors, afm, DME). I predict it will run well, but: 1) Don't let it overheat! 2) Don't miss any shifts! I hope it runs well. With my kiss oil cooler, this thing has a hard time getting warm. I still have the factory oil cooler in the water cooling system too. The external oil cooler actually will pull heat out of the water cooling system. It's crazy how well this setup works. Missing shifts is what I'm worried about. I haven't money shifted a car is quite some time, but I do have 24 bent exhaust valves in my past (2 BMW I-6's). I really need to get some of the slop out of the rear half of the shift linkage. Everything upfront is new, but the stuff by the transaxle is still original. Oh off topic, but did everyone realize the early vs. late rear Koni adjustable are totally different? The early shocks are series 26 and the late series 8040. When I built the car in 2008, I assumed they adjusted like the late and most every rear Koni Sport I've seen--compress the shock and turn. I remember not really feeling the stops when I did this on mine, but I was in a hurry to get the car ready. Turns out, you must remove the dust boot, extend the shock all the way, push a button on the top of the shock body, and then rotate. All this time my rear shock have been set to almost full soft! Glad I figured that one out. -bj Quote Link to comment Share on other sites More sharing options...
loftygoals Posted January 15, 2011 Author Share Posted January 15, 2011 Keeping with my off topic discussion (hey it's my thread, I'll do what I want ) found a little more info about the differences in the early vs. late rear Koni Sport shocks. The early shocks, series 26, are Mono-Tube High Pressure Gas. The late shocks, series 8040, are Twin Tube Low Pressure Gas. The late shocks are rebuildable, while the early are not. It's interesting that Koni used different technology for shocks that are nearly identical in application. -bj Quote Link to comment Share on other sites More sharing options...
loftygoals Posted January 15, 2011 Author Share Posted January 15, 2011 Back on topic: I did a little math and figured out that the cam should be 1.34 degrees retarded with my minimum thickness head vs. the factory 24mm head thickness. -bj Quote Link to comment Share on other sites More sharing options...
loftygoals Posted January 16, 2011 Author Share Posted January 16, 2011 Well, she runs!!! Sounds absolutely awesome! It sounds so much more racy than it did before the rebuild. Started the first try and just idled along happily. Gotta love these little motors! -bj Quote Link to comment Share on other sites More sharing options...
Sterling Doc Posted January 17, 2011 Share Posted January 17, 2011 Congrats! Quote Link to comment Share on other sites More sharing options...
944-Spec#94 Posted January 17, 2011 Share Posted January 17, 2011 Here are some photos of head thickness measurments on a car. This is my street car an 88 944 Turbo S with the original head and head gasket. The number you may just be able to see on the caliper is a stock unshaved dimension not the legal minimum. In a Turbo it takes some getting to, but since I had the engine apart it was easy. For an NA the intake boot probably will need to be removed, but you should have access. I am use a second set of calipers as a straight edge since use the drop indicator on the caliper is not as reliable. The contact surfaces are small and hard get flat and repeatable. The straight edge makes it very repeatable as you have more surface to work with. Also the position of the waterpumpe car vary quite alot so be careful to not pick up off the waterpump surface and make sure you are on the deck of the block. Quote Link to comment Share on other sites More sharing options...
loftygoals Posted January 17, 2011 Author Share Posted January 17, 2011 Using a strait edge is a great idea. Why didn't I think of that? Thanks for the tip! -bj Quote Link to comment Share on other sites More sharing options...
Members Al F. Posted January 17, 2011 Members Share Posted January 17, 2011 Psyched to hear she runs!! Good thing too since there's less than two weeks to go! Quote Link to comment Share on other sites More sharing options...
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