Why is it so hard to get good advice !!???

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**** UPDATE *****
I decided to mount the degree wheel directly to the crank using the stock dampner bolt. This move eliminated all the slop and helped accurately determine true TDC. I degreed the cam and came up with a 73 then a 139 number. This adds up to 212, which when divided by 2 equals 106. I almost crapped myself! The cam card calls for an installed centerline of 106 and I am exactly at 106 with no additional work needed. The timing set is at the ZERO/Dot-to-dot position. The sloppy fitting crank turning hub was giving me a 110 number with the same timing set position. THIS is why I didn't want to assume that the approximate 2 degrees of slop equated to a 108 C/L number. Relying on a degree of slop is still inaccurate.
 
I changed the valvesprings and installed the pushrods, then the rocker arms. I set the lash to the specs listed on the card, but now that I think about it, the engine is cold. I'm sure the specs are probably for a "hot lash". Looking through the enclosed instructions, I didn't see anything mentioned about aluminum heads. It seems that would make some difference, right?
 
I would set them .002" loose cold.
 
RustyRatRod said:
I would set them .002" loose cold.
Click to expand...

To make sure I understand this, do you mean to ADD .002 to the "hot" number of .020 & .022 ?
So .022 and .025 ?
Sounds reasonable to me. Sure feels odd though... Leaving a bit of slop in the valvetrain.
 
I couldn't let sleeping dogs lie. Sometimes my curiousity eats at me!
I looked at the Lunati site and there wasn't any info on setting lash. I looked at some tech archives on a few sites and the most common number for aluminum heads/iron block is .006 tighter than the published hot number. This accounts for the growth that occurs when the engine warms up and expands.
My lash is now at .020 INT and .022 EXH, so I'll RElash them tomorrow at .014 and .016.
Of course I'll recheck after I break in the cam.
 
Because it's brand new - I'd leave the lash loose. The lash is what the manufacturer says, and it's set on a running temperature engine. If the cam has not been broken in then a little extra lash is not going to hurt anything, and too tight may. Set it per manufacturer cold, run the engine to break it in, then when it's hot, adjust one bank of valves to spec with it hot, then seal it up and run it again to ge the other side hot, then set that side.
 
I realize that mine is a SB. I have .037 quench, aluminum heads with 10:1. I can run 89 with no pinging. My cam is 232/237@.050 with .520 lift. I use Rhoads lifters. All this aside, I was told by a mad scientist engine builkder ( did work for Granetelli building engines) that when the quench is over .050 it tends to create turbulance in the combustion chamber. Could this be an issue?
 
Just set them to hot spec, I guarentee you it wont be to tight. Then break it in warm it up good and so forth, pull one valve cover and lash that side to hot spec again. Put VC back on and warm it up again, then do other side. Change oil, then run it about 500 miles check them again in the same sequence. After that I wouldnt be afraid of going 1-2000 miles between checks, depending on what the check before tells you.
 
Frankenduster said:
I couldn't let sleeping dogs lie. Sometimes my curiousity eats at me!
I looked at the Lunati site and there wasn't any info on setting lash. I looked at some tech archives on a few sites and the most common number for aluminum heads/iron block is .006 tighter than the published hot number. This accounts for the growth that occurs when the engine warms up and expands.
My lash is now at .020 INT and .022 EXH, so I'll RElash them tomorrow at .014 and .016.
Of course I'll recheck after I break in the cam.
Click to expand...


do as moper suggested for initial break in..... I have aluminum block and heads... I set my lash using EOIC(solid roller cam) to .006 cold and they grow.012 when warmed up which the cam call for .018 hot. I have a bump button under the hood and I just run thru lash real easy.
 
See, I just knew that if I complained enough, good advice would find its way here!
(Kidding)
Thanks guys!
 
After reading back thru this thread I think you said you went up a good size on the cam and got new springs. You won't run into any coil bind issues will you?
 
Frankenduster said:
I couldn't let sleeping dogs lie. Sometimes my curiousity eats at me!
I looked at the Lunati site and there wasn't any info on setting lash. I looked at some tech archives on a few sites and the most common number for aluminum heads/iron block is .006 tighter than the published hot number. This accounts for the growth that occurs when the engine warms up and expands.
My lash is now at .020 INT and .022 EXH, so I'll RElash them tomorrow at .014 and .016.
Of course I'll recheck after I break in the cam.
Click to expand...

My apologies. I had completely forgotten you had aluminum heads. That does make a difference.
 
You will never get it to "run right" on pump gas with that high of compression! Either get some race fuel or av gas or lower the compression.
 
Frankenduster said:
I'm trying to get the 493 to run right on pump gas. It currently has 10.7 compression with aluminum heads and the cranking compression is between 210-220.
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dartguy340 said:
You will never get it to "run right" on pump gas with that high of compression! Either get some race fuel or av gas or lower the compression.
Click to expand...

I havent seen him post up his cam timing events or cranking compression of new cam yet.
 
dartguy340 said:
You will never get it to "run right" on pump gas with that high of compression! Either get some race fuel or av gas or lower the compression.
Click to expand...

A properly built engine can run on nearly 12:1 with aluminum heads. There's one builder here whose done 11.8 if I remember right. Don't be so quick to say never. It can be done. You might want to read up on quench.
 
That's exactly what he did.
 
A few months back I tested the cranking compression and got numbers in the 210 range...THEN I realized that my compression guage was messed up. The needle started at almost 30 lbs! I retested it with a different guage and the numbers dropped to the 185-190 range.

There are some that told me that I could get it to run right with additional tuning if the spark curve and carb jetting. Others were adamant about lowering the compression. Many thought that the engine would benefit from a more modern cam with assymetric lobes and more aggressive specs.

I didn't want to pull the engine. The cam swap made the most sense to me. The '509 design may have been okay if I wanted to run a 20% mix of 110 octane fuel in the car. It still seemed like a crutch though. I wanted a combination that would run well on 91, even 89 in cold weather if need be.

The switch to the adjustable rocker arms was more of a stepping stone rather than a remedy. The 1.6 ratio actually did even out the compression numbers. The spread between the high and low closed up, showing that the factory stuff really was innacurate. The "after" numbers using the 1.6 rockers show that. The idle vacuum improved with the new rockers to the point where the power brakes actually worked better than before.

This cam swap started awhile ago and has been met with a few obstacles:
Degree or not degree, tight fitting cam, odd looking lifters that may NOT work, sloppy tools giving innacurate readings and then yesterdays poor fitting Jegs windage tray. Thats "Hot Rodding" though....encountering problems and overcoming them.
 
-Sledgehammer- said:
After reading back thru this thread I think you said you went up a good size on the cam and got new springs. You won't run into any coil bind issues will you?
Click to expand...

The springs are rated to .600 even though they are at coil bind at .628. This was according to a tech guy at Summit racing. This cam is at .556/.578 after deducting the lash.
 
Frankenduster said:
I couldn't let sleeping dogs lie. Sometimes my curiousity eats at me!
I looked at the Lunati site and there wasn't any info on setting lash. I looked at some tech archives on a few sites and the most common number for aluminum heads/iron block is .006 tighter than the published hot number. This accounts for the growth that occurs when the engine warms up and expands.
My lash is now at .020 INT and .022 EXH, so I'll RElash them tomorrow at .014 and .016.
Of course I'll recheck after I break in the cam.
Click to expand...

What you are planing IS the CORRECT way to set the valve lash with aluminum heads on a cold engine.
 
Yesterday I pulled the oil pan. I'd been using a chrome pan since I first installed the engine in 2004. It has weeped oil since day one, along with the chrome timing cover. I pulled the MP steel windage tray too, then cleaned the block of all gasket residue. The Milodon 6 quart pan was supposed to be matched with the Milodons oil pickup, so I screwed it in. The Jegs plastic windage tray I bought uses no gaskets. It has thin rubber strips that seal like the plastic 727 transmission pan gaskets that have been out for awhile.
Well.....The Jegs tray wouldn't clear the pickup without trimming, then it wouldn't sit flat against the block. The tray hits the rod caps! For some stupid reason, the dish in the tray is offset about 1/4" to the left, causing it to hit. The right side clears fine. If I shift the tray over to the left about 1/2" , it clears both sides fine but obviously will not bolt up since the gasket rail is offset by the same 1/2". YES, I made sure to order the one for the 4.15 stroke. Maybe they shipped me the wrong one? Maybe it was simply made wrong? I was pissed.
I cleaned up the steel tray, but the dang thing got bent TWICE while cleaning it with the wire wheel. I did some "body and fender" work to straighten it, but I'm not feeling 100% confident that it will seal perfectly. I know that it gets sandwiched and held in place by the oil pan bolts, so it will probably be just fine.
If the Jegs pan they shipped turns out to be the wrong one, I may wait to get the right one before putting the pan back on.
 
What part number is yours tray? I have one for the stock stroke out in the shop. I can compare numbers and if they are the same there's your problem.
 
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