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Discussion Starter #1 (Edited)
Building a 2.2 and I am trying to make as much power as I can. Street car with some AutoX, maybe a trip to VIR. I am taking the time and money to build the engine right. I don't want to settle on an "it's all I could find..." cam.

I would like to be around .470 to .490 lift. With the exhaust being higher. Solid lifter. Thanks y'all.
 

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Pedal Smasher
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I got a custom cam from Charles Goin for my 2.4 CIH. It's based on the Isky OR-77 cam, but designed for hydraulic lifters instead of solid lifters and it has a 110° LSA. I believe it has the same amount of lift and duration. Charles would know more.


This thread has a lot of info on various cams. I think a cam with the amount of lift you are looking for, would be mostly for race use. It can be difficult to get really aggressive on the amount of lift with flat tappet cams. The cam winds up with a lot of duration, which hurts low end power and doesn't make for a street friendly engine. We don't really have a roller lifter option, which would make it easier to go with lots of lift and relatively mild duration.

I'd do the math to figure out what you need. Start with dynamic compression ratio and dynamic cylinder pressure and work backwards to what sort of cam is needed. If you find a cam profile with that much lift, and it works for the intake closing angle with a street friendly amount of duration, then you might have the right cam. I wouldn't want to go for a performance oriented cam without looking at the math. If you get it wrong and the engine turns into a compression monster, you'll have to run race gas just to use it.
 

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Opeler
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I had my custom cam for my 2.2 made by Isky. I gave them a call and they were happy to assist. This was 4/5 years ago though, but worth a shot.
Eric
 

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Discussion Starter #5 (Edited)
As of right now, 3:44. Haven't dove into what's available for rear ends gears yet. I the future I would love to be around 3:90.

Going to be carbed with a Holley 500cfm.

Thanks, Eric. I'll give Isky a call. I'm wondering if they'll sell me a blank. I'm waiting to hear back from a grinder in OR too.
 

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Building a 2.2 and I am trying to make as much power as I can. Street car with some AutoX, maybe a trip to VIR. I am taking the time and money to build the engine right. I don't want to settle on an "it's all I could find..." cam.

I would like to be around .470 to .490 lift. With the exhaust being higher. Solid lifter. Thanks y'all.
I will see if I can find the info on my cam. It was done by Cam Techniques but maybe Isky can grind one.
 

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Discussion Starter #7
Thanks, Jeff.

Thanks, everybody.
Especially Manta Rallier to taking the time to explain DCR to me and learn me a thing or 12. Haha
 

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Intake profile #F315 (.490 lift, 243 @ .050 Duration)
Exhaust profile #F313 (.487 lift, 248 @ .050 Duration)
Lobe separation 108 Deg.
3 Deg. Advance ground in
 
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You get some lope with this cam!
 

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As of right now, 3:44. Haven't dove into what's available for rear ends gears yet. I the future I would love to be around 3:90.

Going to be carbed with a Holley 500cfm.

Thanks, Eric. I'll give Isky a call. I'm wondering if they'll sell me a blank. I'm waiting to hear back from a grinder in OR too.
Ok, time to start looking for 3,91:1 Isuzu Impulse gears then. And if you are going to use an original high port 22E head, you have to modify the stock 2bbl intake to make it fit. I also suspect that a stock 2bbl intake doesn't flow enough to feed the hot cam without the Rally Bob mods. I would consider a pair of 45DCOE's instead of a 2bbl Holley, they have a much better fuel distribution than any 2bbl carb.
 

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Opel Rallier since 1977
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You get some lope with this cam!
I was gonna say..... Yes, this does not look like any sort of 'street-friendly' cam at those .050" durations. What engine size was this in?

And for NC-K9, from experience I'll opine that the Holley 500 is too big. Try a 350. With the 500 you are going to need to re-adjust the main airbleeds considerably to even be close to making it work and it will still probably tend to have a lean bog at lower RPM's. BTDT with the 500.

With your stroker, the engine is going to naturally be more limited in top end RPM. Put in a too-big cam and you will kill the lower RPM torque. The result is going to be a more limited RPM range engine, and unless you have a close ratio trannie, then you're gonna drop off the torque curve in certain gear/RPM combinations. Might be OK for all track racing where you know the gear setups and can match them, but a narrow RPM range engine on the street stinks; you're often searching for the right gear but not finding it.

'As much power as I can get' is a trap for a street engine design. It has to be flexible and have a broader torque range, even if you give up some on peak HP, and particularly so with a manual trannie. I see this all the time in Mopar-land: emphasis on higher dyno numbers but limited RPM range. Works for drag racing and atuo trannies with high stall converters. Does not work well for manual trannies on the street.

A cam for a street app with higher lift numbers needs to have a decently high rate of lift to keep the 'advertised' durations lower, to keep up DCR and thus lower RPM torque, and make the engine more flexible in RPM range. It'll help keep overlap down and help fuel mileage too. That goes away from the traditional Opel and ISKY grinds. Stockish grinds of that era were meant partly for being easy on the cam, lifters, and valve train, for durability of a daily driver engine, and the ramps were LAZY and the lifts were consequently low.

I just profiled an OR-4H and the difference between durations at .006" and .050" lift (at the lifter) was 62 degrees! That is about as lazy as you can get LOL... but easy on the valvetrain. A modern design like a Lunati VooDoo will have a duration difference in the mid 40's. Now there is never a free lunch and so you have to stiffen springs to maintain valvetrain control and that puts more and more force on the valvetrain components. So that is what the OP is in for....
 

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The Holley 500 will work fine Mark, but yes, the cast-in passages are far too large for a 4-cylinder engine. I’ve run them on a street 2.0 liter with great power and driveability.

On a Holley 500 metering block, I typically epoxy the idle feed passsges and the power valve feed passages,, they redrill them to roughly half the original size. Otherwise it will be a miserable, blubbering POS at low to mid rpms.

And you need the appropriate power valve to work with the lower vacuum a hot cam will provide.
 

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It is just that you have to do a lot of that surgery to get it to work all around across the RPM range when it is that oversized. I've done the 500 mods to make the mains work OK but did not do the idle mods, it was for high RPM only . It was indeed miserable at low RPM and the fuel mileage was a lot worse than with DCOE 45's. I just can't recommend it myself. The 350 is going to be a lot less work to get it to run ok.

And when it comes time to fire it up and break in the new engine and cam, having a new and waaay oversized carb is gonna be a mistake, IMHO.
 
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