ProComp/Speedmaster aluminum heads

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j par said:
It seems to me all the trouble of degreeing a cam is lost with a stretched timing chain??..
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You can think of it as Variable Cam Timing... LOL.
But no, I don't think a bit of slop on the chain will throw off your cam timing. I am too stupid when it
comes to computing that... maybe NM9 can do it.
 
j par said:
Lord help me I have to agree LOL...
It seems to me all the trouble of degreeing a cam is lost with a stretched timing chain??..
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It does. Put your degree wheel on and zero it. Then move the crank a bit both ways and read how many degrees the crank will rotate before the cam starts to move.

With slack in the chain like that the cam runs retarded from where you degreed it in at.

I’d buy a tensioner and use it. All chains and gears like that wear very quickly. Look at a motorcycle chain. It will gain length every time it’s new for the first few rides. Same thing here. The chain and gear set up was a “cost effective” way to hook the cam and crank together. But it’s not very accurate.

BTW, I always drill a .040ish hole in the passenger side of the camplate where it covers the oil gallery. I don’t use those dumb soft plugs in there either.

That way you aren’t relying on drip oiling to lube the timing set. You get pressurized oil hitting the gear and if the cam gear has holes in it, the back side of the timing cover. That’s getting oil all over and not relying on the crank slinger (which I don’t use either).
 
j par said:
I talk to Ted about that when the motor was built and he seemed to have no use for it...
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Doesn’t surprise me. Most guys want to run the 100 dollar floating idler junk. The 3 gear fixed idler gear drive is dead accurate, stupid reliable and hard to screw up.

If anyone tells you gear drives cause harmonics, break parts and cost HP, tell them to show you where any ASScar team, any PS team, any F1 team has published that data. It doesn’t exist. The only things I’ve found has been testing done with the floating idler gear system. It’s junk.

All my drag stuff had a GD. With all the crap I broke, never once was there any sign of crank or cam distress from harmonics. Junk lifters did more damage than anything, and a timing chain or belt wouldn’t fix that.
 
no likelihood and I'll probably just go back out to Ted and grab a new timing chain slap it on and be happy for another five years. with all the work I have to do to clean this engine up and get everything else done all I need is another Fiasco.
My bigger concerns are with the cometic head gaskets sealing or not sealing or if I'm going to end up just tossing that stupid 8553 fel pro gasket on there and bich at Summit that they sold them to me for 15 bucks too much because Edelbrock slap their name on them...
I bought the cometic cuz I wanted quality and now they're just becoming a pain in the butt...
 
It’s kinda funny my junk ran 6.0’s when fresh and after 4 years of racing it still runs 6.0’s. Lol. Timing chains rule.
 
j par said:
no likelihood and I'll probably just go back out to Ted and grab a new timing chain slap it on and be happy for another five years. with all the work I have to do to clean this engine up and get everything else done all I need is another Fiasco.
My bigger concerns are with the cometic head gaskets sealing or not sealing or if I'm going to end up just tossing that stupid 8553 fel pro gasket on there and bich at Summit that they sold them to me for 15 bucks too much because Edelbrock slap their name on them...
I bought the cometic cuz I wanted quality and now they're just becoming a pain in the butt...
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LOL that’s why I said just use what you have and use a tensioner. I less than a hundred miles the new one will be just like the old one. They always are.

Timing chains are the least accurate way to time a camshaft. But all the “fast” guys use the so they must be good. Those same “fast” guys don’t use a Dyno becuause they don’t race them.

I’m just trying to save you a bit of coin because the tensioner is like 40 bucks at summit. At least the cam timing won’t change as much.

I’ll see if I can post a link to a less than 100 mile timing set. It wasn’t a cheap set either. Let me see if I can do it.
 
j par said:
Lord help me I have to agree LOL...
It seems to me all the trouble of degreeing a cam is lost with a stretched timing chain??..
Click to expand...
Your right, some will spend hours getting it to the degree, only to lose a couple? LOL. Forget the degree wheel. Put number 1 cylinder on TDC, and then put a straight edge on the exhaust/intake lifters. They should be bevel, no gap. If there is, then move the cam in the correct direction. Use a decent chain set (edelbrock is decent to me - 75 bucks) and never look back.
 
318willrun said:
Your right, some will spend hours getting it to the degree, only to lose a couple? LOL. Forget the degree wheel. Put number 1 cylinder on TDC, and then put a straight edge on the exhaust/intake lifters. They should be bevel, no gap. If there is, then move the cam in the correct direction. Use a decent chain set (edelbrock is decent to me - 75 bucks) and never look back.
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Did you look at the video I posted? Why even degree the cam? When you never test anything you’ll run anything. What I posted was straight junk. If we could have found a gear drive local the guy that owns it would have gladly bought it. Junk IS junk at any price.
 
yellow rose said:
Did you look at the video I posted? Why even degree the cam? When you never test anything you’ll run anything. What I posted was straight junk. If we could have found a gear drive local the guy that owns it would have gladly bought it. Junk IS junk at any price.
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LOL.... I said how I'd check the cam. The old method used by racers at the track when they tore down engines. get the lifters even and your ready.
 
318willrun said:
LOL.... I said how I'd check the cam. The old method used by racers at the track when they tore down engines. get the lifters even and your ready.
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Right...I got what you said. What I said is that where you put it to start? That would be straight up and almost no one does a cam straight up any more (I do most of the time).

Plus, look at your ignition timing with a load on the engine. That mark will move all around. I’ve seen them move 20 degrees. Yeah, that’s great for performance.
 
yellow rose said:
Right...I got what you said. What I said is that where you put it to start? That would be straight up and almost no one does a cam straight up any more (I do most of the time).

Plus, look at your ignition timing with a load on the engine. That mark will move all around. I’ve seen them move 20 degrees. Yeah, that’s great for performance.
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Well, I'm obviously not in support of a loose chain. Neither am I opposed to gear drives. lol. But, a decent chain will survive for years - and proven consistency are in those that bracket race every weekend and the ET doesn't change. Many bracket racers I know run chains, some don't tear their engines down in 3-6 years, and they can dial and run to the hundredth, maybe even thousands of dial in time. Also, the car over the course of that time usually won't slow up - if anything, it will run a couple tenths faster after a 100 runs. Oh, the only way your method of "bouncing 20* under load" works to show chain flop is if the distributor is locked. I'm not trying to educate the educated, but as you say, somebody else might be reading through this thread and I'm just trying to get a perspective out there..... :)
 
318willrun said:
Well, I'm obviously not in support of a loose chain. Neither am I opposed to gear drives. lol. But, a decent chain will survive for years - and proven consistency are in those that bracket race every weekend and the ET doesn't change. Many bracket racers I know run chains, some don't tear their engines down in 3-6 years, and they can dial and run to the hundredth, maybe even thousands of dial in time. Also, the car over the course of that time usually won't slow up - if anything, it will run a couple tenths faster after a 100 runs. Oh, the only way your method of "bouncing 20* under load" works to show chain flop is if the distributor is locked. I'm not trying to educate the educated, but as you say, somebody else might be reading through this thread and I'm just trying to get a perspective out there..... :)
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No, they flop with an advance curve in the distributor too.

So if the chain gets loose and the car goes faster, that tells me the the ICL wasn’t correct for the application. If it’s correct and the cam timing retards they will lose power and slow down.

You also need to run more P/V to make up for the exhaust valve clearance getting eaten up by cam retard.

FWIW most any decent bracket car is running a timing belt any more. Just the stubborn cheap skates run chains. That’s just the truth of it.
 
Well just leaving the shop now and I wanted to know if anybody had any complaints because I do believe the complaint department is up in the air...
IMG_20200527_110232.jpg
 
When you build an engine that the valves kiss the piston every stroke, accuracy is a must .LOL
 
fishmens67 said:
When you build an engine that the valves kiss the piston every stroke, accuracy is a must .LOL
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I found out in the 1970’s they will self clearance when needed. Everything was built with close clearances back then because compression was the only thing we had going for us.
 
So I asked about surface at the machine shop and the answer came back very quick from Ted and Ron that my block definitely has a smooth finish with the high-end machine that they use for such... Also the aluminum heads seem glass like smooth.... He said give the cometic gaskets a light spray of copper seal and let it rip..
 
since I got these issues solved now one of the things that bounces back and forth in my head is putting my electric water pump back on?..
Also I'm going to be curious how this intake manifold lines up with the heads which I'm going to try and get the heads on today so I can clean that lower part of the tunnel ram and see how it drops on there....
 
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