g-50cab

Looks like you are making good progress Ed -

Toby Pennycuff

Nice job Ed. I spent quite a few days trying to find the best way to measure deck height clearance on my 2.4S pistons. The dome makes it very difficult to get right next to the cylinder wall with a dial indicator. I finally resorted to the Competition Engineering method documented in Wayne's book on rebuilding the 911 engine. Acid core solder. Worked like a champ and I could get consistent readings. You're doing great! Keep up the good work.

Ed Hughes

Thanks guys. I told my wife that the work is clean from here on out. I used the acid solder method last time, as there is no way to measure clearance with Motronic pistons and I'd had my heads machined. I've got a new roll of 3mm solder on the bench!

dshepp806

Rock and Roll, dude!!!!!!!!!!

Ed Hughes

Picked up my heads and cam towers today-all nice and clean. But, they'll get a going over anyway.

I checked my clearance betwixt my piston and head, and I've got plenty of clearance, even with the .25mm base gaskets. Coulda lost .25mm and still been good. But, I suppose I had plenty of compression with the big domes, that I could spare a little. I was about .070" clear, probably .010-.020" more than I needed. If I was building a race motor, I suppose I could have the heads flycut...

Along with the chamfer I had machined in the heads for clearance, I didn't like the looks of a few of my exhaust studs, so I had them take the old ones out. A couple were sub-par and snapped, so they machined the carcasses out, and put helicoils in where needed. I figured it was better to do this now, and have good studs in place. All told, just a bit less than $500, so not too bad. Although, this bump in new bits will end up costing almost as much as I paid for the car. With the first build, I'm knocking on $20K into this motor. It better run great!

At any rate, I used the hollow (acid core) solder method to check. Did it twice as I started with the .5mm gaskets, which were too much and dropped back to the set of .25mm stock gaskets I had on hand too. So, nothing to do this weekend, but some more assembly.

mnmasotto

Ed,
Have you ever considered Motec for this car? I just bought the entire M48 system for my car for about 6K. The kit is plug-n-play. This includes a fuel and ignition map, injectors, induction pipe, etc. I am deleting the AFM and using MAP to measure load and air mass. With the Motec engine management you can use any induction system and custom tune it for you exact setup. You could even put on a Vram induction system. Plus it is transferable to another car.
Mark

Ed Hughes

Mark, I think I've considered just about everything for this car. But, I do retain some semblance of sanity on some stuff, at least that is what I tell my wife.

I was pretty close to jumping into an Electromotive setup, but I decided to stick with the DME and splitter. I have fun poking around the car, but I'm not sure I'm capable of supporting something with infinite adjustability.

Amber Gramps

Ed

Ed Hughes

Well, I do my best thinking at 3am when I can't sleep. It dawned on me that I wasn't checking height in the right spot. I ran a couple of more tests today with the solder touching the cylinder wall. This time, I get a clearance of just over .050", which is on the tight side of "stock" settings. Now, I have to decide whether I run this, or go to the .5mm gasket for another .010" of clearance, which would put it on the upper end of tolerance. Decisions, decisions. I know they are engines that run closer to 1mm of clearance, so I've got a 1/4mm of pad as it is. Go for all the power/compression I can, or go a bit more conservative?

EDIT: I'm going to go with the .25mm gaskets. The more I look at this, the more I'm convinced I'm fine with this deck height. Too much clearance would appear to introduce another way to get detonation with the higher compression pistons.

rusnak

Ed: those calipers that you have in the upper picture are made by a company that was founded by Rev. Numata, or "Numata Sensei". He came to the U.S. as a young man to work for my great-grandpa, and never forgot the influence and guidance that that he received in Fresno as a young man. Later, he sold the company and retired very wealthy. He used his money to advance philathropic causes in his later years, including a church in Fresno, CA, USA.

Ed Hughes

I've had those since about 1982!

Eharrison

There's a run tomorrow. You going to have it done in time?

Ed Hughes

No, but I'm going to Bill's house for lunch to check out the stable!

Eharrison

Nice, I'm going to go Palomar and get a short clip of them coming up.

The kids have a school fair tomorrow so I'm SOL on the lunch.

cbad-box

Ed are you working on the motor tomorrow (saturday)? If so when? Turns out I am working on saturday?

Mario