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p79 going hairless


PapaSmurf

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Thanks blue72, that's good info! I was having trouble finding a good faq for the e88s different US versions. I'd heard there were 4 versions. So this particular e88 should get me lower compression than your earlier e88 would then. That's what I wanted to know! So I should be right around 10:1 with the felpro gasket. Dancing on the edge of premium here at sea level

 

edit: It hurts to get bit by that grinder, these exhaust valves are just covered in lead deposits. Gotta get them clean though, every bit of material I remove from them means that much less compression. I'm also cleaning the tops of the pistons. ugh. Sometimes it feels like this hobby is all about cleaning. Clean the engine, clean the interior, wash and wax etc... it will all be worth it though

Edited by PapaSmurf
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You can still see the 3 angles on these valves and the head, but they are worn down in some places, rounded in others. I wish I had a machinist in town. I don't know if they could even re cut a valve that probably wouldn't help much would it.. oh well they should seal well enough. I'll have to start saving up for all new valves on the p79

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Well I've almost got the porting work done. I was going for quick and dirty but the ocd took over and I actually did a pretty good job smoothing it all down and removed quite a bit of material. It should flow quite a bit better. Now I was thinking of "molesting" this e88 -to use your words blue72. Just removing a small amount of material with the dremel from the combustion chambers. Any thoughts? I'm sure it's been done before.

 

One final thing - I've been staring at this head for hours on end and I just realized that the combustion chambers are not perfectly circular. Not by a long shot. These can't match up with the cylinders perfectly, or the head gasket either for that matter. I was wondering if anyone else had noticed this and what the opinion is about it's effects.

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Well im going to try this again...

 

When you do any kind of porting it is wise (should be done this way) to use a gasket to match it to....doesnt matter if its square, round, oval, etc as long as it matches the gasket because obviously it is all about flow.

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Well im going to try this again...

 

When you do any kind of porting it is wise (should be done this way) to use a gasket to match it to....doesnt matter if its square, round, oval, etc as long as it matches the gasket because obviously it is all about flow.

 

Thanks sticky, I've already done that. I was thinking of taking it to the next level and matching the manifolds to the gasket too but my rotozip arm is tired. I installed the springs over my newly cleaned valves. I also removed a very very very small amount of material from each combustion chamber to try to keep compression lower. I also smoothed out the last few threads for the spark plugs that protruded into the combustion chamber, I heard somewhere that those could get hot and cause pre-ignition which is going to be my worst enemy. So compression on this head should be significantly lower than it was before I cleaned it up, and ever so slightly lower than it was stock. Now I just have to polish the cam and rockers up. I can't believe this head came off a running motor.

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I have a new set of lash pads that were for the stage 1 cam I ordered off the z store a long time ago. These lash pads do not have the recess at the bottom of them, they sit slightly higher than the stock lash pads. I was wondering if they were safe to use with the stock cam on this set up, the flat tops come up pretty high, I'm not sure how much clearance the valves will have. Any thoughts?

 

these are .180 solid lash pads from msa, I'm thinking that they should work fine as long as the wipe pattern is alright, I'll have to test

Edited by PapaSmurf
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Mk well like i said...always make sure its all the same size...if you have a Gasket matched/ported head...wouldnt make much sense if you didnt port the Manifold going to them?? Think of a vacuum with a tube attachment (since your engine is sucking air in the intake, and pushing it out the exhaust) now make your thumb&pointer into a circle (think OK sign) and block the ridge....makes no sense to port the suction part for more air when you have to suck it through a smaller hole.

 

PortMATCH everything

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Thanks sticky, I got the head bolted on, the timing chain and everything. I checked the wipe patterns and discovered that these brass valve seats are bad. This head is unusable. I wasted some time. So I suppose I get to start working on that p79. And while I'm at it I might tinker with the fuel injection. are there any good resources for cleaning up the fi system? The only thing I have is the manifold, injectors, vacume lines, etc whatever was bolted to the engine. This z came with FI originally but the PO removed the brain under the drivers side dash. I figure if I can't get my extra performance from higher compression perhaps I can get it elsewhere. So I'll port match the head and intake/exhaust manifolds and I'll be running the more modern electric distributor that came with the f54, and maybe FI - if I can get it to look clean enough with the stock manifold and wiring harness. I need to find an ecu and a FI wire harness. I get mad sometimes when I think about those 2 280z parts cars I had to get rid of. Every time I need a part I remember having at least 2 of them bah. I want to see what I can do to make a stock FI system look and operate better. 90% of why I dislike FI is the mess in the engine bay.

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the p79 is nearly clean, started pulling the valves out and brushing them. It's so much easier than the older head that ran leaded fuel. I'll have this head finished this week. Then I gotta pull the e88 off the block, bolt this head on, get it all buttoned up, pull the old engine from the car, mate this one to the other clutch and tranny, replumb the fuel lines for the electric pump, rewire the ignition system, and put the hood back on. bah this is taking too long... I want to drive!

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Finished the port work and matching, Got the head installed on the block, timing chain on, valves adjusted, etc. I pulled the old engine and transmission, after I swap clutches and mate the transmission to the new one I can put it in.

 

Pics:

tinymechanic.jpg

My tiny mechanic

 

pullthatengine.jpg

It's out.

 

oldtrannyengine.jpg

Every good l28 goes to heaven.

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