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Zguy91

L28ET Cam Swap

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Converting the head to solid is fairly easy with thread adapters for the solid rocker posts. Then just install the new cam, and check the wipe pattern. My P90A head happens to be factory solid. I didn't convert this one.

 

 

 

 

I always reference this chart for cam info. The early A is not drilled for oil, I am not sure about the later A cams.

 

http://www.atlanticz.ca/zclub/techtips/cam/index.htm

 

Is there an advantage to this rather than going with a non-hydraulic lifter head?

 

This tompic has peaked my interest, but I have a p90a Hydraulic head.

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Mines an 83 so its hydraulic

:rolleyes:

 

OMFG...

 

TWO of the THREE I got in the shed came from 83's. The year, the casting... MEANS NOTHING--you can say you have Hydraulic when you have LOOKED and CONFIRMED it.

 

How hard is this? :huh:

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Let me translate my own post. A P90A/H with a solid kit installed, including a correct cam, is equivalent (performance-wise) to a P90 that came with solid posts.

 

I don't know if they varied the coolant chamber design between the two heads.

 

 

Edited by cygnusx1

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I am bumping this thread as it is relevant to what I intend to do to get my S30 turbo back on the track this spring with Megasquirt. Some of you know I wiped a lobe on my Schneider cam earlier this year, so I want to swap another cam in to get the motor working without a cam break-in to worry about while tuning the MS.

 

I pulled an E31 head from a scrapyard engine, and the cam looks good. There is some bearing surface wear, but I'm hoping that doesn't create an immediate issue -- the lobes on the factory cam all look good. So I am going to swap the towers, spray bar, rockers and the "A" cam to my P90.

 

I am installing an E31 "A" Cam, rockers, and matching external oil towers with spray bar into my L28ET/P90A solid "lifter" (rocker post) engine. The full engine rebuild will start today and proceed for the next couple of weeks. Based on the info here, I should have a nice gain in top end with some possible mid range torque gains. Will report my butt dyno results, of course. Any word from the OP and the "C" cam?

 

I've done quite a bit of searching and reading up on these cam swaps, but I still have a couple questions, and of course any comments on this swap are welcome.

 

The lash pads are of course worn, and I have kept them with the associated (and numbered) rocker arm. Assuming the wipe pattern is centered on the rocker arm, is it ok to reuse the lash pad or do I need a new one? If I can re-use the lash pad, does it matter if it is installed 180 degrees around (I didn't document orientation)? I suppose I can mark the lash pad surface like the rocker surface and ensure the pattern stays within the wear area...

 

Tell me if this is false economy. I am just trying to get a valve train up and running with a new fuel computer, and then I intend to re-do the valve train properly, perhaps with another set of externally oiled cam towers once I have a reasonable tune. I don't want to worry about a cam break-in without a reliable tune.

 

And I am also interested in feedback from the OP on any aspect of this swap, or anyone else regarding used cam swaps and/or results of the 240 cam in a turbo engine.

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I guess you can put the lash pads 180 degrees different from one another, but I believe the bottoms are machined to be completely flat, so it really shouldn't matter. I've had 3 different cams in my car now, and have not worried about lash pad orientation, only proper thickness. No issues yet!

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I don't expect to run this cam for very long, so I guess I will not worry about it. Hopefully my rebuilt head with it's Schneider springs and existing installed valve height (factory valves) will not force me to a different lash pad when I swap in the used A grind cam and matching rockers. I will find out for sure when I check the wipe pattern.

 

Thanks CamH.

Edited by SleeperZ

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Do you have any other stock pads that are in good shape (not a lot of wear)? If you do, use them as the orientation won't matter. I have a huge bag of them. I could probably put a set together in decent shape.

I have an untouched P90A (non-hyd) that I could pilfer, but I may take you up on that offer as these have quite a trench in them.

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Stock NA cams work better than the stock turbo cam in my experience. good for another 500 rpms.

 

You can run NA cams as long as the cam is internally oiled (1977 on up). no spray bars on P90 heads. In other words, you need to use NA cam from a N47 or P79 head.

 

This be true with the stock ECU?

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