CamH Posted September 7, 2011 Share Posted September 7, 2011 (edited) I'm posting to see if any of you fellow L-series guys have bothered putting aftermarket cams in your hydraulic lifter P90A engines. I currently have a P90A head with factory turbo cam, and it will not pull past 5500RPM without taking a serious dive in power. I want to correct this. In my parts supply, I have a nitrided MSA (Schneider) Stage II Turbo cam made for the hydraulic head. I also have an extra head with good factory A grind camshaft, lifters, and a set of timeserts for the conversion to solid lifter, kind of avoiding this because I would need to swap cam towers (which requires head gasket swap) as my A grind cam is externally oiled. I'm just trying to figure out what my best option would be. Also, I am running a larger T3/TO4E 60 trim turbocharger with stage III exhaust, and about 18PSI, and I have an aftermarket intake manifold (lonewolf) and full 3" exhaust.. Edited September 7, 2011 by CamH Quote Link to comment Share on other sites More sharing options...
BluDestiny Posted September 7, 2011 Share Posted September 7, 2011 Is there any work done to the head currently on? if not just build a solid lifter head on the side and go all out. Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted September 7, 2011 Share Posted September 7, 2011 Im not entirely sure why you are trying to avoid a head gasket change. Pretty easy to be honest. Also when you change out the camshaft, Schneider recommends changing the valve springs as well, to the Heavy Duty Valve springs. This is a bit of a pain to be honest. Basically you keep the cylinder head on the block, rotate the crank by hand with a 26mm wrench and use a valve spring compressor. The valves will hit the top of the piston and will allow you to remove those stupid valve spring retainers with a magnetic tool. Changing the head gasket is easy though, especially if you have a metal head gasket. Speaking of, I have one for sale if you need one. I'm also not sure why removing the cam towers would require lifting the cylinder head? Lifting the bolts out sure, but you don't need to change the head gasket.. as far as I'm aware. Quote Link to comment Share on other sites More sharing options...
CamH Posted September 7, 2011 Author Share Posted September 7, 2011 (edited) Well, I believe cam tower removal requires the removal of the nuts off of 5 of 7 head studs so I'm not sure that the head gasket would keep a seal. It's a felpro, not metal. I wanted to kind of keep the head gasket as a "fuse" in this setup. I think I am going to put the Schneider cam in today, and see what happens. If I can widen out my power band a little, I'll be happy for now, and can build a new head later. edit: Will post back later with butt dyno results, and VE change under boost. Edited September 7, 2011 by CamH Quote Link to comment Share on other sites More sharing options...
z-ya Posted September 8, 2011 Share Posted September 8, 2011 Don't just slap it in there and see what happens. What is the cam lift? What about springs, lash pads etc.? Check all that stuff before putting it in to find out that the springs are weak, and the lash pads are wrong. Then you'll be takin' the head off for sure. Quote Link to comment Share on other sites More sharing options...
CamH Posted September 8, 2011 Author Share Posted September 8, 2011 Yes, I believe I have the correct lash pads for this setup. I will be checking everything before starting the engine of course. Cam lift is 460/460 which, to my understanding, is fine on stock valve springs. I believe these are meant to be mostly a drop in affair. The engine has ~5000 miles since rebuild and the valve springs were replaced with new ones during rebuild. I was hoping to have things done today, but didn't quite have time to get it buttoned up. Will hopefully be posting back with good results tomorrow! Quote Link to comment Share on other sites More sharing options...
z-ya Posted September 9, 2011 Share Posted September 9, 2011 Why do you think you need to remove the head to swap cam towers? You can run the new cam (internally oiled?), with a spray bar (I do on my race engine). Are you switching to solid lifter at the same time? I'm not sure how to check the rocker wipe pattern on a hydraulic P90A. I would think that you would need oil pressure to pump up the lifters to get an accurate wipe pattern. Quote Link to comment Share on other sites More sharing options...
macambra Posted September 9, 2011 Share Posted September 9, 2011 (edited) Be wary of the Schneider turbo cam. I purchased one for my 83 turbo with the p90A head. The cam I received was NOT for a hydraulic head as advertised. I had to swap to adjustable lash adjusters. If the paper that came with the cam specifies a lash adjustment it is for a mechanical type head. With the stock hydraulic adjusters the cam had .035" clearance. Just FYI. I have heard of others with the same story. With that said, I bought the .460" lift cam and it STARTS making power at 2300 and I have taken it up to 6500. It is a ffresh rebuild and I don't want to push it untill I break it in. Edited September 9, 2011 by macambra Quote Link to comment Share on other sites More sharing options...
CamH Posted September 9, 2011 Author Share Posted September 9, 2011 (edited) Why do you think you need to remove the head to swap cam towers? You can run the new cam (internally oiled?), with a spray bar (I do on my race engine). Are you switching to solid lifter at the same time? I'm not sure how to check the rocker wipe pattern on a hydraulic P90A. I would think that you would need oil pressure to pump up the lifters to get an accurate wipe pattern. Cam tower removal requires the removal of 5 out of 7 head bolts on the manifold side of the engine. I'm not sure that I would trust a factory-style head gasket after doing that. If I had an MLS head gasket I would probably try it. Thoughts? Be wary of the Schneider turbo cam. I purchased one for my 83 turbo with the p90A head. The cam I received was NOT for a hydraulic head as advertised. I had to swap to adjustable lash adjusters. If the paper that came with the cam specifies a lash adjustment it is for a mechanical type head. With the stock hydraulic adjusters the cam had .035" clearance. Just FYI. I have heard of others with the same story. With that said, I bought the .460" lift cam and it STARTS making power at 2300 and I have taken it up to 6500. It is a ffresh rebuild and I don't want to push it untill I break it in. Thanks, I'll call them to verify in the morning. Like I said, I have a set of solid adjusters and timeserts so not a huge deal. I hope you're teasing me with that power band though, because it sounds FANTASTIC! Edited September 9, 2011 by CamH Quote Link to comment Share on other sites More sharing options...
z-ya Posted September 9, 2011 Share Posted September 9, 2011 (edited) Cam tower removal requires the removal of 5 out of 7 head bolts on the manifold side of the engine. I'm not sure that I would trust a factory-style head gasket after doing that. If I had an MLS head gasket I would probably try it. Thoughts? Duh, yea, your probably right. You would have to re-torque the head. If you don't want to run the spray bar with the internally oiled cam, MSA sells little block off plates, or you can make your own. But again, it doesn't hurt to use the spray bar. I would suggest converting to solid lifters so you can set the lash correctly, and then confirm the wipe pattern is correct. Get this wrong, and your cam will be junk in a matter of seconds. Also, after breaking in my race motor with it, I suggest using the RedLine break in lube for a new cam. It has a very high ZDDP content, and will ensure that the cam breaks in correctly. Thanks, I'll call them to verify in the morning. Like I said, I have a set of solid adjusters and timeserts so not a huge deal. I hope you're teasing me with that power band though, because it sounds FANTASTIC! That is about what my NA 460 lift cam did, so it should be similar in a turbo application. Edited September 9, 2011 by z-ya Quote Link to comment Share on other sites More sharing options...
CamH Posted September 11, 2011 Author Share Posted September 11, 2011 Just to confirm, Schneider DOES NOT make a hydraulic cam. The cam mentioned in this thread (and listed on the MSA website as a 1983 280ZX Turbo P90A only head) is for solid setups. If anyone has any info on actual aftermarket hydraulic cams, feel free to share (I am not sure that there are any.) So, I went ahead and put in the solids in with the nitrided Schneider turbo cam. I haven't started the car yet, but plan on buttoning up a few things and retuning tomorrow. Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 11, 2011 Share Posted September 11, 2011 The stock turbo comes in below or around 2200, so it deceives you somewhat of the cams capabilities. It sounds a lot like a 240 or 260 cam in the same turbo application, same sort of boosted performance when before just N/A you felt the cam 'come on' at a higher rpm (like 3000-3500 torque peak at 4000) the massively improved breathing below peak torque makes for a very flat torque curve--so much so in fact that it feels like an NA pulling from 2200 without any 'turbo surge' it just pulls and pulls and pulls. Till the normal cam dynamics gives out. Same power curve, just moved up on the power graph vertically. Incidentally, this is how a properly designed turbo system should work. Boost Threshold should be significantly below cam peak torque and VE best points... makes driveability much easier and takes away all the turbo 'bad habits' from the 60's and 70's. Common question heard is "This is a turbo car?" I suspect the Hybrid you have 'comes on' and gives full boost at around 3200, so you will feel the car surge in power when the turbo 'kicks in'... Though if the cam has the extra lift getting even 3psi before boost threshold may make enough difference that the bottom end pre-boost-threshold portion of the rpm range is fattened up enough that you feel the car pulling from well before that point. Then when you take the turbo off, you go "where did all my pre-boost power go?" I know that's what I did! Quote Link to comment Share on other sites More sharing options...
Brad-ManQ45 Posted January 11, 2020 Share Posted January 11, 2020 (edited) Sorry to bring this thread back from the dead, but I just had a conversation with Schneider cams and they DO make one hydraulic grind for the P90A head. It is the mild grind good to 6000 rpm. They supply the specific lash pad thickness to use on a by cam basis after grinding due to the smaller base circle since there is no way to ascertain the measurement with hydraulic setup. Just wanted to make sure the proper info is available. The nice thing about the cam is the 114 degree lobe centers. Edited January 11, 2020 by Brad-ManQ45 Quote Link to comment Share on other sites More sharing options...
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