High compression blues.

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RustyRatRod said:
I like somethin like this for it.

RB & B Series Mopar Solid Lifter Camshaft
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That's a good cam and would make some steam, but,

Same duration as the Hyd cam he has now. Need to close the intake valve later. I think he needs to be in the 305-315 range to get the pressure in some sort of usable range. Also not install it advance, has to go in straight up and likely on a 110 or higher LSA.

Just my guess based on the current cam being 292 duration installed on a 106 CL.
 
crackedback said:
That's a good cam and would make some steam, but,

Same duration as the Hyd cam he has now. I think he needs to be in the 305-315 range to get the pressure in some sort of usable range. Also not install it advance, has to go in straight up and likely on a 110 or higher LSA.

Just my guess based on the current cam being 292 duration installed on a 106 CL.
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Same advertised maybe, but 10* or so bigger at .050.
 
Most in here know I'm not a fan of wide lobe separation cams. I prefer them cut on a tighter LSA. Usually because the sticks are going in lower compression engines. This is the exact opposite situation.

In this case the engine needs reduce compression, so cutting a cam on a 112-114 LSA, installed straight up, will help with a later closing intake valve, reducing compression pressure. It might even help the idle manners as cam is going to be a bunch larger. It's about the ONLY time I'd suggest such a camshaft.
 
A gear ratio change may be in order... or a converter adjustment
 
crackedback said:
Most in here know I'm not a fan of wide lobe separation cams. I prefer them cut on a tighter LSA. Usually because the sticks are going in lower compression engines. This is the exact opposite situation.

In this case the engine needs reduce compression, so cutting a cam on a 112-114 LSA, installed straight up, will help with a later closing intake valve, reducing compression pressure. It might even help the idle manners as cam is going to be a bunch larger. It's about the ONLY time I'd suggest such a camshaft.
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Maybe if he could find the 508 MP cam that was ground on 112. lol Didn't they do one for big blocks too?
 
hosehead said:
Near Rob's duration specs but have yet to find one on a 112 or 114 lsa.
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Anybody will grind you one. Call Schneider and get them to grind that one I recommended on a 112. They'll do it right quick like.
 
Just one thing for thought. Larger duration cams do bleed off compression ........at low rpm. The scavenging effects of long duration lots of overlap will actually build more compression at high rpm. That is why putting a big cam in your car tends to make it doggy off idle and pick up in the upper rpm range. This is where the OP is saying he has the pinging issue. Large cam may make it worse. His best bet would be eithe find some gas that can operate under these conditions or find thicker head gaskets to add ccs to the combustion chamber.

I have a motor in the works right now that I expect to have the same issues with. I have a .060 383 with 11.5 to 1 compression ratio. It is going in a car shortly.
 
Actually, camshafts do not bleed off compression and duration really has little to do with it. It's when the intake valve closes. A later IVC will build less cylinder pressure than one that closes earlier, because the intake closes later, allowing the cylinder to not be filled as completely, so "bleed off" is technically incorrect. Air normally trapped in the cylinder, will simply end up in the intake manifold. While duration does play a role, it's the IVC that you really should pay attention to.

Here is a pretty good article about valve events.

https://www.mechadyne-int.com/app/u...ation-on-engine-performance-and-emissions.pdf
 
rumblefish360 said:
Small block cam.
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I gotta thro in here, I run a 292 extreme solid roller, '' about " the same specs as rrr suggested, w/ the hughs 1/6 rockers, its about .620./ .628 on lift , 440/505" wedge. It may not be the perfect cam, but it`s a lot like the old 590 cams, only a little hairier. It is very docile on the street, until u stick ur foot in it, not hard on valve train,. I run alum. raised port heads, and 91 pump gas, 10.3 c.r. , icon dished pistons, cometic .039 thick gaskets, (good quench at about .037-.039 ), loose 3500 convertor, 21 initial , 34 all in at 3400, 44 total cruising. , no pinging. ---- (I have posted this many times), '', IF U NEED MORE OCTANE, GO BUY A CAN OF B 12 CHEMTOOL F.I. CLEANER , $2.99 A CAN, EVERYTHING IN IT IS AN OCTANE BOOSTER, ABOUT 5 DIFF. KINDS! And it works ! I don`t run any at times and have no pinging, but will run it at the track if I ever get around to taking the fish out there. The roller set up is a little more expensive, u can find all the stuff needed on ebay, and save a few $ . Hughs engines has a steel dist drive gear that will work w. a billet cam, I have one in mine. U can make it all work. My first street hemi had 205-210 pounds per cyl. stock, of course it would ratlle w/ ethel in it back than, had to use a little something extra for it too.
Tell me about ur avatar pic.!!!!
 
hosehead said:
Autolite 3924, runs best where timing is now. Not sure about the gasket. Im pretty sure they were out of the fel pro kit. I'm calling the builder on Monday. The block was previously uncut. Only surfaced when engine was rebuilt. Hope to have some more info on Monday after a talk with the builder.
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Haven't tried 1 or 2 heat ranges ( -23, -22) down on the plugs?
 
famous bob said:
I gotta thro in here, I run a 292 extreme solid roller, '' about " the same specs as rrr suggested, w/ the hughs 1/6 rockers, its about .620./ .628 on lift , 440/505" wedge. It may not be the perfect cam, but it`s a lot like the old 590 cams, only a little hairier. It is very docile on the street, until u stick ur foot in it, not hard on valve train,. I run alum. raised port heads, and 91 pump gas, 10.3 c.r. , icon dished pistons, cometic .039 thick gaskets, (good quench at about .037-.039 ), loose 3500 convertor, 21 initial , 34 all in at 3400, 44 total cruising. , no pinging. ---- (I have posted this many times), '', IF U NEED MORE OCTANE, GO BUY A CAN OF B 12 CHEMTOOL F.I. CLEANER , $2.99 A CAN, EVERYTHING IN IT IS AN OCTANE BOOSTER, ABOUT 5 DIFF. KINDS! And it works ! I don`t run any at times and have no pinging, but will run it at the track if I ever get around to taking the fish out there. The roller set up is a little more expensive, u can find all the stuff needed on ebay, and save a few $ . Hughs engines has a steel dist drive gear that will work w. a billet cam, I have one in mine. U can make it all work. My first street hemi had 205-210 pounds per cyl. stock, of course it would ratlle w/ ethel in it back than, had to use a little something extra for it too.
Tell me about ur avatar pic.!!!!
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Thanks Bob! I'll check that cam out. Not sure if a roller is in the budget at the moment though.
Also, born in Tulsa, raised in Broken Arrow, college in Norman and now I'm stuck in California, lol.
 
doubt you can find it easily in california but converting your carburetor to E85 would solve all your issues i run 11.5 to one compression on a 505 wedge with aluminum heads with no pinging whatsoever, honestly i only chose to go with it because i didnt want to chance detonation issues running 91, as well as having to cut back on ignition timing, basically didnt want to be forced to hold back my motor from what it really wants just a suggestion as im not sure e85 is widely available in cali
 
How many miles do you actually drive the car a summer?
Instead of spending money making it run worse, just buy better fuel for it
 
Not to mention, that I am looking to upgrade performance anyway, as stated earlier in the thread.
 
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