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Opel Rallier since 1977
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You’ll probably mock me for it, but I typically run street engines with factory forged rods/cast pistons at .005” to .007” above deck, with a .032” thick (compressed) gasket.
I ran race engines for years at .010” above deck with the same gasket thickness.
You're a brave man, Bob! But lots of quench/squish that way.... Was that for cast pistons (tighter clearance, not much piston rocking) or for forged too?
 

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I specifically told them not to take any more off the block than just a cleanup cut because I was afraid of getting into timing issues as I've seen posted on here from others
I guess my block went through the mill one to many times. I’ve got the .051” Cometic head gasket, pistons are .010” above and a modified cam gear to adjust the cam timing and get it where the card says it’s supposed to be.
FF645BB7-B4EA-42EB-9CF3-25E1F0C569A2.jpeg
 

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Opel Rallier since 1977
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Yes it is hydraulic lifters
OK you have to make sure that the lifters are essentially solid when doing the valve-piston clearance. If not, then the valve spring pressures will collapse the lifter as the lobe starts to raise it, and will give a too-shallow impression on the clay.
  • One way to do this is to take the pistons out of a couple of the lifters, pry out the check balls and their little stamped retainers from the bottom of the pistons, and then put in a nut or something in the bottom chamber to fill the bottom chamber with solid material. (Just make sure it does not contact the check ball seat in the center of the bottom of the piston... hence a nut is good.) Then reassemble the lifters and set the valve lash to zero with the rocker adjusters and do the test. Then reverse the lifter 'mod' process afterwards.
You could use a couple of old lifters for this if the bottom are not yet worm to the point of being concave.

Hopefully your new valve springs will prevent any valve float and and lifters subequently pumping-up.
 

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Discussion Starter #44
OK you have to make sure that the lifters are essentially solid when doing the valve-piston clearance. If not, then the valve spring pressures will collapse the lifter as the lobe starts to raise it, and will give a too-shallow impression on the clay.
  • One way to do this is to take the pistons out of a couple of the lifters, pry out the check balls and their little stamped retainers from the bottom of the pistons, and then put in a nut or something in the bottom chamber to fill the bottom chamber with solid material. (Just make sure it does not contact the check ball seat in the center of the bottom of the piston... hence a nut is good.) Then reassemble the lifters and set the valve lash to zero with the rocker adjusters and do the test. Then reverse the lifter 'mod' process afterwards.
You could use a couple of old lifters for this if the bottom are not yet worm to the point of being concave.

Hopefully your new valve springs will prevent any valve float and and lifters subequently pumping-up.
that is the hope. we started with looking at the pontiac 400 double valve springs rallybob recommended but the machinist wanted to try something different i believe due to weight maybe?
 

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Discussion Starter #45
I guess my block went through the mill one to many times. I’ve got the .051” Cometic head gasket, pistons are .010” above and a modified cam gear to adjust the cam timing and get it where the card says it’s supposed to be.
View attachment 429181
with this being the first time ive rebuilt a motor and hopped it up im trying to keep it as simple as i can (so i dont screw it up ). ive seen people post about doing this same thing but wasnt confident i had a clear enough grasp to ensure it was executed correctly
 

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You're a brave man, Bob! But lots of quench/squish that way.... Was that for cast pistons (tighter clearance, not much piston rocking) or for forged too?
.010” above deck with JE pistons set to .004” clearance.
 
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You have a much better grasp on the changes needed to the timing with that clearance than I do haha. I'm trying to be safe where I dont screw it up while following your writeup for a hot street head
Deali
with this being the first time ive rebuilt a motor and hopped it up im trying to keep it as simple as i can (so i dont screw it up ). ive seen people post about doing this same thing but wasnt confident i had a clear enough grasp to ensure it was executed correctly
Compensating for cam timing is really no big deal..... Matter a fact it's still in your best interest to do the cam gear with Chevy bushing mod as 3 degrees of cam advance helps mid range torque in our street 2L engines
 

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that is the hope. we started with looking at the pontiac 400 double valve springs rallybob recommended but the machinist wanted to try something different i believe due to weight maybe?
No worries, as long as the spring rates work out and there’s no coil binding, you should be good.
 
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That is the tightest piston-head clearance.I have ever heard....makes me worry less now. Tnx!
And for clarification, it spent all its time between 5700-9400 rpms. Also had a 2.2 crankshaft so piston speed was higher.
 

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Discussion Starter #51
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This morning was a morning full of cleaning sandblasting and then putting the first coat of primer on. Not pictured are the pulleys brackets and block off plates etc. Slowly moving forward. Tomorrow morning will be second coat of primer and then paint. Also dropping the motor back off at the machine shop to fix goobered up manifold bolt holes and have the piston to valve clearance checked. (Less likely that the motor catastrophically fails if they do it).
 

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All the cleaning and painting takes some time. But it needs to be done. Are you using a primer for aluminum? (I don't konw much about that matter....)

I'd recommend that you ask the shop how they plan to make the hydrualic lifters 'solid' for this test. There are other ways to do it (like a partial fill of the lower chamber of the lifters with oil but that has to be done cautiously to not over do it), but if you are going to pay for the work, you want to make sure it is being done in a way that gives valid results.
 

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Discussion Starter #53
Yes I primed the aluminum with a self etching primer and then today I have just finished the low gloss black for all the parts. Valve cover will get a bit of body color razzle dazzle once I get everything I need for it (pinstripe the fins and opel stamp) I need to clean up the oil cap still as I didn't want sand inside it to fall out once its together ill use a scotch Brite on the Dremmel and then it'll get the same low gloss black and a simple little pinstripe number.
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Discussion Starter #54
Theyre not perfect but theyre much better than this nasty looking clear coat that was on them before
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Just be careful....Sotchbrite grit is carbide and will tear up metal inside an engine quite well. It's always sumpthin', ain't it....
 

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Discussion Starter #57
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Had a paint shop a few towns over make up some paint to match the original copper brown metalic (theres sticker residue you can see on the gas lid thanks to previous owners affinity for them) they did a better job than I did wielding a paint brush.... not surprising. But overall I am pretty tickled with it
 

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Discussion Starter #58
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Not nearly as happy with the oil cap. Took too long to pull the tape off and put the paint on to thick in sections so the it didn't lay flat. Probably will start the oil cap over after my 5 day vacation.
 

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Discussion Starter #59
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She's definitely a 5 foot looker as she sits. I may flip the colors on the oil cap and do the blitz and outer ring in orange and see if it looks better but until I get back this is how she'll sit.
 
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