Ported 452 or Edelbrock RPM

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Well, the dynamic seems a little high perhaps. What are the cam specs?
Good quench is at a max of IIRC, .050? I'm not remembering right now.
The worse the quench, the more prone to pinging it is.
I run .039 on my 360. I have run tighter, but it gets a little scary. Better than stock rods are a good move for tight clearances. There is less streching of the rod during higher rpm runs. Thus, keeping the piston away from the heads.
 
rumblefish360 said:
Well, the dynamic seems a little high perhaps. What are the cam specs?
Good quench is at a max of IIRC, .050? I'm not remembering right now.
The worse the quench, the more prone to pinging it is.
I run .039 on my 360. I have run tighter, but it gets a little scary. Better than stock rods are a good move for tight clearances. There is less streching of the rod during higher rpm runs. Thus, keeping the piston away from the heads.
Click to expand...

Perhaps my calculator is wrong? ;-)

Cam is 245/253 @ .050
Intake closes at 62.5 degrees.
Lift is .640
Manufacturer says static minimum 10.0:1 with this cam.

I think 0.045 is what I should be happy with for quench, some say 0.035...
I have forged rods and pistons so was hoping that when all gets up to temp I will be very close to 0.050 which is from what I heard max for good quench.

I guess I will just start this thing tomorrow and see what is what.
 
You have good cooling? Run it. Run good fuel when racing; it should be fine on the street on your unleaded premium pump fuel unless you get too aggressive with the timing.

Do you have 100LL aviation gas in Europe? That would be more than sufficient octane. S/F....Ken M
 
EchoSixMike said:
You have good cooling? Run it. Run good fuel when racing; it should be fine on the street on your unleaded premium pump fuel unless you get too aggressive with the timing.

Do you have 100LL aviation gas in Europe? That would be more than sufficient octane. S/F....Ken M
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I have the biggest 4 row radiator that I could fit ;-)
I am running only equivalent of your 93 around 50/50 with 100 octane shell gas.

With timing, total is 34 degrees and I'm all in at around 2500rpm, should I change to around 3000 to be safe?
 
Those steel shim gaskets might really screw up the sealing surface or the heads. Steel on aluminum isn't a good combo.

Copper coat isn't going to help that issue. I hope you didn't use the stuff in a tube.
 
If it's the same RON+MON/2 octane rating, that fuel should be OK for street driving. Run the straight 100 for racing, even better if you can find some 100LL. I'd go with the less aggressive timing, just to be safe for the street. "Moar power!" is never really a big block issue on the street unless it's a really sick engine or something is very out of scope in the build. S/F....Ken M
 
I never put three angles on the valves unless I've done a TON of testing and even then it's almost never.

I almost never back cut a valve anymore so it doesn't surprise me the valve has just one angle on it. That's how it should be.
 
crackedback said:
Those steel shim gaskets might really screw up the sealing surface or the heads. Steel on aluminum isn't a good combo.

Copper coat isn't going to help that issue. I hope you didn't use the stuff in a tube.
Click to expand...

I used permatex copper spray, and I am really not sure what to think about all negatives about steel shims.
I heard from some C guys ;-) that steel shim with copper was used in Corvette engines from factory.
Also people tell me that I should check torque on head bolts after some miles in.
I guess steel ring in Felpro 1009 gasket leaves a mark in heads as well no?
 
OK I started it today and put some miles on. I used NGK plugs with 7 rating.
First of it started right up, it was really great as if nothing was done to it.
No pinging at all, sounds really mean, you can feel it in your chest.
Also no leaks which I was worried about due to all the negatives about my steel shim gaskets choice.

While I was swapping the heads I also replaced thermostat with new 180 degrees rated and it really did the job. Car goes up to temp in no time and keep 190 all the time.

After putting some miles on I revved it a bit and checked acceleration, all I can say is I am sure it is better. Revs like a small block, I will post a small movie to show.

Now I finally need to take my 727 off to fix front seal leak and do dyno test.
 
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yellow rose said:
I never put three angles on the valves unless I've done a TON of testing and even then it's almost never.

I almost never back cut a valve anymore so it doesn't surprise me the valve has just one angle on it. That's how it should be.
Click to expand...

Can you be more specific as to what negative could you possibly have form valve back cut?
Everybody I talk to says it can only help flow at very low lift.

Please spare some time and try to give me some info. So far this forum made me learn a ton os stuff, more information wont hurt.

My Koffels ported 452 heads had valve back cut when I got them.

FC582C24-ABE0-406D-A3F5-7275DAB6B365.jpeg
 
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EchoSixMike said:
If it's the same RON+MON/2 octane rating, that fuel should be OK for street driving. Run the straight 100 for racing, even better if you can find some 100LL. I'd go with the less aggressive timing, just to be safe for the street. "Moar power!" is never really a big block issue on the street unless it's a really sick engine or something is very out of scope in the build. S/F....Ken M
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You mean I should back off from 34 total or change springs to reach 34 later?
 
Here is how it revs:

It idles at 950 in park and 750 in gear.
 
How many of you have used a single layer thin steel head gasket with an aluminum head on an iron block and have had problems? Huh? Or are you just talking about something you have never tested? Repeating rumors? I have never tried it, so any response from me would have no validity.
 
IQ52 said:
How many of you have used a single layer thin steel head gasket with an aluminum head on an iron block and have had problems? Huh? Or are you just talking about something you have never tested? Repeating rumors? I have never tried it, so any response from me would have no validity.
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I did it one time, for a hemi that was going to Austrailia. IIRC, they were a Fel-Pro shim gasket and naturally, they had a batch that were stamped wrong. The customer brought in all his own parts, including the head gaskets.

On the dyno we had an oil leak. After screwing with it for awhile I pulled the heads. When they stamped the gasket, they put a runner (I *THINK* that is what the guy at Fel-Pro called them) out of place right where it passed by an oil feed hole.

Pressurized oil would go out into that runner (channel) and leak it out at the back of the head. Fel-Pro sent out a corrected gasket and all was well. Those runners are supposed to capture air and when the head is torqued that is what seals the head as it tries to move away from the block.

I have done many aluminum intakes on cast iron heads and never had an issues but everything has to be clean and flat. I don't tell other people to do it because it's easy to screw up.
 
Miszny said:
You mean I should back off from 34 total or change springs to reach 34 later?
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The second thing; slower rate of timing advance until higher rpm.

I find that a back cut intake increases flow, on the bench anyways. And breaking the outer edge of the exhaust valve also helps, since flow is "reversed". In a perfect world, I'd turn a radius edge on a lathe. Think of how air wants to flow, then take steps accordingly. There are other factors in consideration also, you don't want sharp edges, particularly on exhaust valves, for example.

This isn't large gains, but if you have the time and resources, it generally doesn't cost much $. In rules restricted stuff, you scrabble for every little bit. S/F....Ken M
 
EchoSixMike said:
The second thing; slower rate of timing advance until higher rpm.

I find that a back cut intake increases flow, on the bench anyways. And breaking the outer edge of the exhaust valve also helps, since flow is "reversed". In a perfect world, I'd turn a radius edge on a lathe. Think of how air wants to flow, then take steps accordingly. There are other factors in consideration also, you don't want sharp edges, particularly on exhaust valves, for example.

This isn't large gains, but if you have the time and resources, it generally doesn't cost much $. In rules restricted stuff, you scrabble for every little bit. S/F....Ken M
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I have msd retarder box that has curve programmed to start advancing from 1000 till 3000. It retards 20 degrees for easier start and brings it back up at 3000. Perfect for locked distributor setup.
I’m thinking to finally install it and lock my distributor.
I just did the same curve in my msd distributor with springs and it seems that car runs cooler and had better gas pedal response from lower rpms.
How would you setup the advance?
 
Small followup.
I learned my lesson regarding valve lash and all those recommendations for cold lash and adding or subtracting certain amount. Please find table for this added to this post. It worked well for me with all iron setup, but did not with aluminum heads.
In my case subtracting 0.006 for cold was off to the point of unacceptable.
My cam manufacturer recommends 0.022" but given that I use 1.6 ratio rockers I always used 0.023" and it worked perfect. I tried cold lash at 0.017" and effect was slow revs and vibration at high rpm.
Finally in this setup subtracting 0.003" worked well. It gave me exactly 0.023" on hot engine and car still runs really nice till it gets to temp.

Crane_lash_table.jpg
 
yellow rose said:
I never put three angles on the valves unless I've done a TON of testing and even then it's almost never.

I almost never back cut a valve anymore so it doesn't surprise me the valve has just one angle on it. That's how it should be.
Click to expand...
sure trues them up and makes`em look good tho! A hair liter, and most of the ones I have had back cut showed a small improvement ???????????????
 
Miszny said:
Small followup.
I learned my lesson regarding valve lash and all those recommendations for cold lash and adding or subtracting certain amount. Please find table for this added to this post. It worked well for me with all iron setup, but did not with aluminum heads.
In my case subtracting 0.006 for cold was off to the point of unacceptable.
My cam manufacturer recommends 0.022" but given that I use 1.6 ratio rockers I always used 0.023" and it worked perfect. I tried cold lash at 0.017" and effect was slow revs and vibration at high rpm.
Finally in this setup subtracting 0.003" worked well. It gave me exactly 0.023" on hot engine and car still runs really nice till it gets to temp.

View attachment 1715171950
Click to expand...


It really depends on several factors. What you posted are rough guidelines. You take a BBC or a Hemi and and they will grow much more than that.

I've tuned all aluminum blown alcohol engines that lashed at .004 cold and ran at .024 hot.

Also, I've never seen an all cast iron engine lose lash with heat.
 
yellow rose said:
Also, I've never seen an all cast iron engine lose lash with heat.
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Ah ha, finally someone else who has noticed this! I followed that old tale of .002" looser until I checked it for myself. And .002" lash difference doesn't mean squat anyway unless you take the time to test the performance differences of various lash settings on your personal engine.
 
Regarding steel gaskets, I talked to a buddy of mine that services infinity cars and he says all v6 engines have steel shim head gaskets from factory.
He gave me multiple examples of other modern cars that also have them also.
So far no leaks in my case.

But I have another problem, vibration at high load.

My trans angle is 2 degrees down in relation to the ground, rear end is 1 degree yoke down. I have SS springs and pinion snubber.
I put 4 inch shims today as this is the only thing I had. Will test tomorrow.
How much twist is possible? How many degrees up can my rear end go under load?

I guess I will need to find a better topic for this. Can any of you guys suggest something?
Shimmed it looks like in the photo.
Seems a bit crazy, my understanding is that in irder for it to be good, rear axle would need to twist up by 7 degrees to end up parallel to the transmission that is if transmission angle remains unchanged which is not the case I bet.

8A1DEEF1-3C82-46EC-A714-521F5E07EA4C.jpeg
 
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Settings from the photo are night and day VS what I initially had.
Not only vibration is gone but also I get much more traction!
It’s to the point that my rear view mirror tilts back and my wipers and lights knobs fall of my dash and hit me ;-)
 
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