Tony D Posted September 7, 2011 Share Posted September 7, 2011 (edited) No, it was in reference to the cam in the head of the engine I was giving as an example. We kept the same cam, but with the displacement change, the power peak happened at a different point in the rpm range. This is a common occurance in the VW World where guys really get to liking a cam in a 1600 or even 1835, and spec it for another engine and it's WAAAAAY overkill for the larger engine. Or opposite---they like the specs in a big motor, and when they build the smaller engine, they're dissapointed that the characteristics of the cam change so much. It's one thing here that people fail to take into account. One thing that works great in an L24 will work differently in a 3.0 and vice-versa. We had fueling problems on the Dyno last week, so new numbers from the 2.8 are not complete. Something like 256HP at the rear wheels but that was only at 6500 rpms (Different Cam from last time in the above examples.) The power comes on above 6K, so it was just starting to build when the map went full rich and started misfiring. Wish I could have been there... Edited September 7, 2011 by Tony D Quote Link to comment Share on other sites More sharing options...
inline6 Posted October 15, 2011 Author Share Posted October 15, 2011 My custom JE pistons have arrived... Now we have to see if they were made to the correct specification. If so, we should be able to start building the thing in earnest now. Quote Link to comment Share on other sites More sharing options...
z-ya Posted October 15, 2011 Share Posted October 15, 2011 Nice. Check the dimensions before doing anything for sure. If all looks good, you might want to consider Swain coating. Another $300 or so. You have to bore after you have the coated pistons in hand so the clearance is correct. I sent a set of 25 year old Cosworth pistons out for coating and they came back looking like new. Quote Link to comment Share on other sites More sharing options...
luvemfast Posted December 5, 2011 Share Posted December 5, 2011 Any updates on this? I've just installed mine over the weekend. Ran pretty bad, had to re jet the carb's. Then went like sh*t out of a shanghai. No dyno sheets yet Quote Link to comment Share on other sites More sharing options...
inline6 Posted December 9, 2011 Author Share Posted December 9, 2011 Ok, an update: Block (N42) is back from the machine shop. They left about 4 thou for final honing (final sizing). Also, the main caps were ground a touch and the crank main bore was align honed - probably overkill. I am looking for a torque plate... If I can't find a suitable one to use then I will just have the final hone done without it. Head bolt/stud hole location is such that the distortion on these blocks (when compared to many) isn't a big issue. Anyway, happy to pony up money to rent one, if that is what it takes. The fun stuff, (actual assembly) is not too far off! Quote Link to comment Share on other sites More sharing options...
Nelsonian Posted December 9, 2011 Share Posted December 9, 2011 Might try bhjdynamics.com Quote Link to comment Share on other sites More sharing options...
cockerstar Posted December 9, 2011 Share Posted December 9, 2011 I know Bryan (1 fast z) has a torque plate. Maybe he would be willing to rent it out? http://bandmzcars.com/ Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted December 9, 2011 Share Posted December 9, 2011 I haven't seen 1fastz on in a long time! Wonder where he's been?! Quote Link to comment Share on other sites More sharing options...
cockerstar Posted December 9, 2011 Share Posted December 9, 2011 I haven't heard anything, but you could try dropping him an email at buick_36@yahoo.com The shop's number is (602) 258-3219. http://bandmzcars.com/torqueplate.html Quote Link to comment Share on other sites More sharing options...
inline6 Posted January 31, 2012 Author Share Posted January 31, 2012 Crank, flywheel, pressure plate, and disc, etc. are being balanced. The crank was 2-3 grams out of balance... The brand new Fidanza 10 lb. aluminum flywheel was 8 grams out... Looks like I'll be final honing without the use of a torque plate. My engine builder is going to try to torque the head on and take some measurements to see the cyl wall deflection. We'll see... Should have some more pics and more frequent updates going forward as we are getting ever closer to assembly, or rather, mock-up! Quote Link to comment Share on other sites More sharing options...
inline6 Posted February 29, 2012 Author Share Posted February 29, 2012 The last of the parts I had to round up are en route... Attaching a pic of the fittings installed in new holes above the #5 and #6 exhaust ports. They are placed at the top of the cooling passages - as high as my machinist could get them without cutting threads into the top of the passage surface. Lots more pics coming soon... Stay tuned. Quote Link to comment Share on other sites More sharing options...
inline6 Posted March 2, 2012 Author Share Posted March 2, 2012 Some pics of crankcase vent mod - to install fitting with o-ring. I will run a hose from here and the valve cover vent into a catch tank. Quote Link to comment Share on other sites More sharing options...
inline6 Posted March 7, 2012 Author Share Posted March 7, 2012 (edited) This is the high capacity pump that I am reusing. Looks like a few nice chunks of stuff have been through here. One of them was stuck in the soft aluminum housing... was able to pick it out Raised edges were removed. Rotor polished up in the process. Also modded the inlets and outlets for better flow. More exciting stuff coming before long. Edited March 7, 2012 by inline6 Quote Link to comment Share on other sites More sharing options...
cockerstar Posted March 7, 2012 Share Posted March 7, 2012 Looking good man! Really digging the crankcase modifications and that head looks great! Do you have any numbers to share from when your machinist checked the cylinder wall deflection? I'm curious to know how significant it is Quote Link to comment Share on other sites More sharing options...
inline6 Posted March 17, 2012 Author Share Posted March 17, 2012 (edited) So, the machinist is working hard on my project now. He torqued the head on - I'm using ARP studs, and then measured bore deflection. The worst place only measures a total of 4 tenths out... that is 4 ten thousandths of an inch. He measured in various places and most of the deformities were 2 tenths or less. And the worst was additive - 2 tenths one direction and 2 tenths in the other (or something like that). Guess what folks? That is pretty friggin' good. Combustion pressures are what? Hmmm. Over a 1000 psi, maybe? I'm guessing that the cylinder walls might deflect a tad with that kind of pressure? Anyway, I feel pretty ok about not using a torque plate for the final hone. Edited March 17, 2012 by inline6 Quote Link to comment Share on other sites More sharing options...
inline6 Posted March 31, 2012 Author Share Posted March 31, 2012 A few pics... Unfortunately JE did not cut the dishes in the pistons as we wished. The machinist had to remove some more material to get the piston dish cc where I wanted it. Now, they have 11cc volume including the valve reliefs. My calculations put the engine compression ratio at 11.15 to 1. Here, the pistons are all cleaned up: Bryan, my engine builder, has finished sizing the rings to the bores. The oil expander gap is too big with the expanders that came with the pistons. Bryan said they were producing only 4 lbs. of oil ring drag, so we have to go up one size. Those have been ordered. And lastly, the crank is sitting in the block for mock up. We need to put the rods and pistons in to see where the pistons are going to end up relative to the deck. Because I am trying to get as much quench as I can with my E88 head (milled lots!), I will be running piston to head clearance of the thickness of the Nismo head gasket - .6mm (.024"). Quote Link to comment Share on other sites More sharing options...
inline6 Posted April 15, 2012 Author Share Posted April 15, 2012 (edited) Just got some more photos from Bryan, my engine builder. The pistons have been put in the motor for the first time in order to see the relationship with the deck. Measurements are written on them. Along the pin axis, they are basically flat with the deck. One side verse the other, the variance is about one to two thousandths. The plus and minus numbers at the 6:00 and 12:00 positions are the measurements made when rocking the pistons. +7 for example is the amount that the edge of the piston rocks up and out of the cylinder bore. The Nismo gasket I am going to be using measures .025" in the non-ridged area (just the flat portion). It should not compress any during installation. Specs given by BRAAP and Brian (BandMZcars) in some posts say .022" is the minimum to run for piston to head clearance. I've not seen anything about compensating for piston rocking. So, hopefully, the .022" takes this factor into consideration. With + .000" on some of the pistons and the .025" gasket, I'll be at .025" "static" - if you will. Glad to see the pistons from JE came out to spec in this regard. Edited April 16, 2012 by inline6 Quote Link to comment Share on other sites More sharing options...
inline6 Posted May 2, 2012 Author Share Posted May 2, 2012 Another update... I am just about out of tensioner travel due to surfacing what I calculate to be .107" off of cylinder head since it was virgin. The bolt washers are hiding the remaining slot clearance - about .080" to .100". Also, I had to use up almost all cam gear adjustment to get the cam to 100.5 Intake Center Line. Cam degreed in/checked out as: Intake- 281* @ .050 valve lift (Cam/follower lash .010) .549 net lift at valve 100.5* Intake centerline Exhaust- 267* @.050 valve lift (Cam/follower lash .010) .542 net lift at valve 108.5* Exhaust centerline Cam measures 104.5* Lobe seperation. Cam is advanced 4* from "straight up". PTV on the exhaust is only .082"... and on the intake is only .002" More machining of pistons to add PTV is necessary! Quote Link to comment Share on other sites More sharing options...
duragg Posted May 2, 2012 Share Posted May 2, 2012 I am sure you and your engine guy already know, but adjust your timing cover to match the block if you have done shaving. At the last minute on my build I found a pristine lower timing cover I decided to use, but somebody had shaved it in the past and it leaked. Quote Link to comment Share on other sites More sharing options...
inline6 Posted May 3, 2012 Author Share Posted May 3, 2012 At the last minute on my build I found a pristine lower timing cover I decided to use, but somebody had shaved it in the past and it leaked. Ohhh... yeah, I could see that one tripping people up. Thanks for the head's up. Quote Link to comment Share on other sites More sharing options...
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