BurnoutZ Posted July 30, 2008 Share Posted July 30, 2008 I was browsing msa and I noticed they sell a stage 2 performance turbo cam for 83' only... Does this mean it would work with a p90a head? From what I understand the p90a head and a big cam dont get along? Quote Link to comment Share on other sites More sharing options...
Challenger Posted July 30, 2008 Share Posted July 30, 2008 Hmm, never thought of that. It may not be that drastic of a change in lift that it doesnt affect it. Quote Link to comment Share on other sites More sharing options...
BurnoutZ Posted July 30, 2008 Author Share Posted July 30, 2008 It has less lift than the NA cams msa sells but the same lift as the 81-82 stage 2 turbo cam... .460/.460 Quote Link to comment Share on other sites More sharing options...
Challenger Posted July 30, 2008 Share Posted July 30, 2008 Im not sure why they put 81-82 turbo and 83 turbo. Why isnt it 81 turbo and 82-83 turbo? Quote Link to comment Share on other sites More sharing options...
BurnoutZ Posted July 30, 2008 Author Share Posted July 30, 2008 Wasnt 81-82 the P79 and P90's.... 83 the P90a? Quote Link to comment Share on other sites More sharing options...
Challenger Posted July 30, 2008 Share Posted July 30, 2008 Oh yeah my bad got it backwards.. drr.. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted July 30, 2008 Administrators Share Posted July 30, 2008 This has been covered in depth on this and other Z car forums.. Recap; '81-'83 ZX were assembled and distributed in the US with these cylinder heads; ALL N/A cars = P-79 head. ALL Turbos = P-90/P-90A heads. NOTE!!! SOME P-90A heads, not all P-90A heads, utilize hydraulic lash adjusters. SOME P-90A heads utilize the mechanical lash adjusters same as all other L-6 heads. NOTE, part duex; ALL mechanical L-6 camshafts are interchangeable, from the first 240-Z to the last 1983 280-ZX and 1984 L-6 Maxima. The hydraulic camshaft that was available in the P-90A head can NOT be used with mechanical adjusters, and vice versa. Mechanical and hydraulic cams have very different opening and closing ramps on the cam lobes, as such, you MUST keep hydraulic cams with hydraulic adjusters, and mechanical cams with mechanical adjusters, period! Regarding this MSA Turbo cam. MSA could have very easily had typo or the ad department doesn’t have a clue about Z cars. Best bet is to contact them directly and ask to speak to a tech, savvy Z car valve trains and ask him/her if this is a hydraulic or mechanical camshaft. Remember, the only criteria you need to be concerned with is, is the cam ground for Hydraulic lash adjusters or mechanical adjusters. If the cam is ground for hydraulic lash adjusters, then it will ONLY work in a P-90A head ONLY if that P-90A has the hydraulic lash adjusters. Only a visual inspection with the valve cover removed will reveal if any P-90A head is hydraulic or mechanical. Outside of that, the casting number on the head and the vehicle year means squat diddly. Quote Link to comment Share on other sites More sharing options...
1 fast z Posted July 30, 2008 Share Posted July 30, 2008 Actually, HYDRO cams can be used in a MECH valve train, but a MECH cam cannot be used in a hydro setup. This is because on a hydro cam, it has a VERY steep initial ramp for a few degrees to all it to "seat" the hydraulic Plunger inside the lifter. If you do not have this steep initial ramp, like on a mech cam, the lifter wont ever seat and you will get bleed down during the duration of the on cam cycle. Quote Link to comment Share on other sites More sharing options...
BurnoutZ Posted July 30, 2008 Author Share Posted July 30, 2008 So a P90a head is just a P90 head that may have hydraulic lifters? I was under the impression they always had hydraulic lifters... Why did nissan make some of the P90a heads without hydraulic lifters? Was it a mistake in production or does the P90a flow differantly than the P90? Quote Link to comment Share on other sites More sharing options...
Vintage Posted July 30, 2008 Share Posted July 30, 2008 Aside from the hyd lifters/cam, the P90A is just like the P90, in regards to champer size/shape, and port size/shape. Quote Link to comment Share on other sites More sharing options...
BurnoutZ Posted July 30, 2008 Author Share Posted July 30, 2008 So why did they brand it P90a if it had solid lifters? Was this a mistake or has a conversion been done? Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted July 30, 2008 Administrators Share Posted July 30, 2008 So why did they brand it P90a if it had solid lifters? Was this a mistake or has a conversion been done? Not sure how or why some P-90a’s came from NISSAN Hydraulic and others were not. Nissan released them that way, and some people have converted others. The Nissan released Mechanical P-90a heads are not a conversion. The adjuster bosses are machined just as all other mechanical heads, no oil port to the oil galley, same stock adjusters, etc. The Hydraulic P-90a heads have larger adjuster bores, and when the converted to mechanical, will have an insert installed in the larger adjuster bore so the stock mechanical adjusters can be used. 1 fast Z may know more about this. Here is a thread with pictures of a factory mechanical P-90A, (it was a surprise to me then as well)… http://forums.hybridz.org/showthread.php?t=113246 Quote Link to comment Share on other sites More sharing options...
1 fast z Posted July 30, 2008 Share Posted July 30, 2008 From my Conclustions It looks like ALL 83's have hydro, to where late 82 cars have P90A heads that are solid, thats from cars I have seen or pulled heads on. I have I think 4 SOLID P90A's on the shelf, so they are pretty common. Quote Link to comment Share on other sites More sharing options...
Brad-ManQ45 Posted July 30, 2008 Share Posted July 30, 2008 I for one would LIKE to see a good cam that will work with the P90A. Something on the order of 114 degrees lobe centers with a bit longer intake/exhaust duration and a bit more lift that will work with stock spec springs. ( sinced ther is a bit more duration, you can provide a bit more lift that the stock spec springs can control - and the hydraulic pivots can handle. We could wind up with a cam good to 6k instead of 5200 rpm and still have good driveability and response. This only because I am building my '83ZXT with a conversion to a GM 4L60E tranny, and as many of you probably know, it's RPM's, not HP or torque that kill automatic trannies (if you don't believe me go to LS1Tech.Com and see what happens when people have NOX and then get a bigger cam allowing 500 more rpm - they're fine with the NOX, but as soon as they start turning 6.5K+ rpm the automatic transmissions go south on them). If I ever blow up my engine, when I rebuild it (unless I go with a Toyota 2JZ), I'll ask Isky or Schneider or whoever if they can handle grinding a hydraulic that would work on the P90A (I already know that Webb Cams won't do more than a 112 separation angle). Quote Link to comment Share on other sites More sharing options...
Challenger Posted July 30, 2008 Share Posted July 30, 2008 Why not convert your p90a to solid lifters? Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted July 30, 2008 Share Posted July 30, 2008 Bryan when I converted my P90a head to solid lifters.. I kept the hydraulic camshaft in and did not have any luck.. it make terrible noise as the higher ramp profile on the hydraulic cam slapped into the lifters.. I spent hours adjusting the mechanical lifters and using different lash pads and never had any success... I ended up using a P90 head I had as a spare and used the mechanical lifters with a mechanical camshaft and everything worked out for me. So I don't know if using a hydraulic cam would work with mechanical lifters.. I did not have any luck with it Quote Link to comment Share on other sites More sharing options...
BurnoutZ Posted July 31, 2008 Author Share Posted July 31, 2008 Aside from the fact that camshafts are easier to get for mechanical lifters, Are there any advantages to having hydraulic lifters? Ex - If you put a tuned big cam into a mechanical head vs a tuned big cam in a hydraulic head.. Are they the same in performance? Quote Link to comment Share on other sites More sharing options...
Challenger Posted July 31, 2008 Share Posted July 31, 2008 No, from what I know the hyd. will begin to float at high rpm. Also they can "deflate" at any time and you cant get new ones. Quote Link to comment Share on other sites More sharing options...
Tony D Posted July 31, 2008 Share Posted July 31, 2008 No, from what I know the hyd. will begin to float at high rpm. Also they can "deflate" at any time and you cant get new ones. Define "High rpms"---most people making power through boost have a power peak below 6500rpms (most definately if they are using the stock cams) so why would one 'need' to go to any higher rpms? Who voiced these 'floating' problems, does anybody know of anybody who actually did this, or is it all heresay? I pretty much know the answer, but I have to ask, just to make people think... Quote Link to comment Share on other sites More sharing options...
Brad-ManQ45 Posted August 1, 2008 Share Posted August 1, 2008 I like the fact that the engine is quieter, and I don't have to adjust valves. As my '83 will be my daily driver, the less time I have to spend on maintenance is more time to restore/fix my '75Z... Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.