ZSaint Posted October 11, 2005 Share Posted October 11, 2005 I know that P90 heads have solid adjusters. Some of the P90A heads have both solid and hydraulic lifters. I am wanting to convert a hydraulic P90A head to solid lifters/adjusters. Are the solid adjusters on a P90A the same size (dia) and thread pitch that are in the P90A? How about the solid adjusters on the P90A head. Are these the same size and thread pitch that are used by the hydraulic lifters? I know you cannot use the older-style solid lifter/adjuster on the P90A head. How about the solid adjusters on the P90 or P90A head? Quote Link to comment Share on other sites More sharing options...
1 fast z Posted October 12, 2005 Share Posted October 12, 2005 All L6 L series adjusters are the same. The thread pitch is not the same, nor is the diameter. It is NOT a direct bolt in, as threaded, externaly, and internaly bushings need to be made. Going off of crappy memory, I beilive the threads on the adjusters, are 18mm, and the A head is 21mm. Quote Link to comment Share on other sites More sharing options...
ZSaint Posted October 22, 2005 Author Share Posted October 22, 2005 You are correct! I just thought that I might find a miracle fix. I took the solid cam out of the P90A head and put in a hydraulic cam and the engine ran just fine. So much for the "you can run a solid cam in your P90A", trick. No way! Quote Link to comment Share on other sites More sharing options...
blairjj Posted October 23, 2005 Share Posted October 23, 2005 Howdy, Me and another member from zcar.com bought Timesert adapters to convert our P90a heads over to solid lifter. It's basically a "heli-coil" that has an external thread that matches the P90a bosses and an internal thread that matches the solid lifter thread. They are rather cheap (~$3 a pop). Check it out... http://www.timesert.com Good luck, Jay Quote Link to comment Share on other sites More sharing options...
aarang Posted October 24, 2005 Share Posted October 24, 2005 Hey blairjj, what part number from timesert did you use? Quote Link to comment Share on other sites More sharing options...
ZSaint Posted October 25, 2005 Author Share Posted October 25, 2005 Great information! Please, what part number did you use. I need to order a set for my P90A head. Quote Link to comment Share on other sites More sharing options...
ZSaint Posted October 25, 2005 Author Share Posted October 25, 2005 I installed a stock '83 ZXT camshaft and the problem is solved. The engine runs very well. It took awhile for the lifters to react but it smoothed right our in a couple of minutes. I drove my restored '71 for the first time. It ran very well. Now I will order a performance cam from Bull Frog Cams and see how it goes. Quote Link to comment Share on other sites More sharing options...
ZSaint Posted October 26, 2005 Author Share Posted October 26, 2005 I e-mailed timesert. They responded that they do not have any thread over 18mm. Dang! Quote Link to comment Share on other sites More sharing options...
blairjj Posted October 26, 2005 Share Posted October 26, 2005 I'm on travel this week for work. I will track a part number down for you guys when I get back early next week. Zsaint... I'm not sure if the info that you got... I have received and installed these parts and I can assure you that they fit fine... Let me check on a part number. Thanks, Jay Quote Link to comment Share on other sites More sharing options...
blairjj Posted November 1, 2005 Share Posted November 1, 2005 All right guys, Alex Avery from zcar.com has posted the following info on his research for converting the hydraulic lifters on a P90a to solid: Alex says... Just wanted to report the result of my efforts to find a cheap alternative to convert P90A hydraulic lifter head to solid lifters. It can be easily accomplished for about $35 bucks. Because the hydraulic lifter bosses are already WAY countersunk, you only need to buy 12 20mm Timesert thread inserts for $2.71 each (+shipping) rather than the expensive tool kit (which includes a thread tap, insert countersink tool, and thread locking tool you won't use). When you get the threaded inserts from Timesert: 1. Remove the hydraulic lifters 2. Thread the Timesert inserts into the lifter bosses until they bottom out 3. Install solid lifters. The solid lifters are a LOT shorter than the hydraulic lifters. The hydraulic lifter bosses are pre-countersunk in a way, as the threads are only at the bottom of the lifter boss. So the threaded insert when installed is below the top-deck of the head. The solid lifters aren't as long as the hydraulic lifters, so they only engage the thread inserts in the first 5-6 threads. But seeing as the lifters see only compression forces, not tension forces, 5-6 threads are plenty to hold the lifters into the head. I took lots of pics and will post a short, well illustrated "how-to" article on the net when I find the time. So all those P90A heads out there should now be considered viable and cost-effective alternatives to P79s. Details: http://www.timesert.com The Timesert item number is 18153 (M18x1.5x18.3 INSERT) Time Fastener Co 5301 Longley Lane Reno, NV 89511 (775) 829-1026 I have these and used the solid lifters from a P79... works like a charm! Be sure to drop by zcar.com and thank Alex! Jay Quote Link to comment Share on other sites More sharing options...
Guest blivet523 Posted December 3, 2005 Share Posted December 3, 2005 When you converted to solid lifters did you notice that the solid lifters dont compleatly cover oil port in lifter boss? On mine you cant see the small sliver due to beveled edge of lifter, but when motor is cranked over and builds oil pressure it runs out of all 12. The bottom end still builds pressure but those "leaks" will drop oil press to all valve train components, and your oil pressure gauge wont show it. Let me know what you think im looking for thin washers to fix problem. Quote Link to comment Share on other sites More sharing options...
DemonZ Posted December 6, 2005 Share Posted December 6, 2005 Thanks Jay, Can't wait to see the write up! Quote Link to comment Share on other sites More sharing options...
DemonZ Posted January 4, 2006 Share Posted January 4, 2006 When you converted to solid lifters did you notice that the solid lifters dont compleatly cover oil port in lifter boss? On mine you cant see the small sliver due to beveled edge of lifter, but when motor is cranked over and builds oil pressure it runs out of all 12. The bottom end still builds pressure but those "leaks" will drop oil press to all valve train components, and your oil pressure gauge wont show it. Let me know what you think im looking for thin washers to fix problem. How about the ghetto fix-all "JB cold weld epoxy" to plug the oil passage? Quote Link to comment Share on other sites More sharing options...
Guest RaiZed Posted January 6, 2006 Share Posted January 6, 2006 OK, so what is the differance between a P90 w/solid lifters and a P90A w/ solid lifters????????....... what Im getting at is this. Check it out please. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1,1&item=8027911907&sspagename=STRK%3AMEWA%3AIT My 82 ZXT has a P90 I am interested in this P90A (the price is unbeliveable, for now) what do you guys think........ Is this a bolt on item for my engine? should I be weary of such a great deal? Quote Link to comment Share on other sites More sharing options...
DemonZ Posted January 6, 2006 Share Posted January 6, 2006 I don't think there is a difference in 90 vs 90A if they are both solid, maybe someone converted from hydrolics to solid. I don't think anyone has done it the other way around as there is much more work involved. It seems I have seen that head on ebay before... The seller sounds like a member here, maybe he will chime in. Quote Link to comment Share on other sites More sharing options...
Junkman Posted January 7, 2006 Share Posted January 7, 2006 Verbiage: They're 1.5mm thread, as are the solid lifters. Hydro are 20 x 1.5 x 28 (total lifter length). Solid 18 x 1.5 x ~19mm. http://www.timesert.com The Timesert item number is 18153 (M18x1.5x18.3 INSERT) Time Fastener Co 5301 Longley Lane Reno, NV 89511 (775) 829-1026 Alex '77 280Z '68 2000 roadster Quote Link to comment Share on other sites More sharing options...
ZSaint Posted March 9, 2006 Author Share Posted March 9, 2006 Thanks for this info. I just got the message. I bought a new computer and lost my "favorites". I now have "Hybrid Z" back on. I just went through the drill of machining an old set of hydraulic lifters and a set of solid adjusters to make them work in the P90A head. What a deal! A buddy of mine (Andy Barcheck) has a lathe and is very meticulous. He did the fine work including silver soldering the solid adjuster into the shortened hydraulic base. We could've had a V8! (Timesert) I have pics of our work if anyone is interested! Quote Link to comment Share on other sites More sharing options...
ZSaint Posted March 9, 2006 Author Share Posted March 9, 2006 I think a thin flat washer mounted between the solid adjuster and the head will solve this problem. The washer will cover the oil hole in the head. Maybe you can get some valve spring shims for small v/springs? I know this will move the adjuster up 1/16 of an inch but we have lots of room. This way you can re-use the hydraulic lifters if you ever want to do it. (Who would do that!) Quote Link to comment Share on other sites More sharing options...
73ZCAR Posted March 10, 2006 Share Posted March 10, 2006 Zsaint , I have a head exactly like the one shown in the e-bay auction (EARLY p90a). It is identical to a regular p90 head that I just picked up the other day. Mike Quote Link to comment Share on other sites More sharing options...
ZSaint Posted March 10, 2006 Author Share Posted March 10, 2006 I am guessing you must look at the adjusters/lifters in order to determine whether a P90A head is solid or hydrualic. You cannot tell by just the designation. Quote Link to comment Share on other sites More sharing options...
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