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Discussion Starter · #21 ·
Thanks for the info, the numbers look so small compared to the ones for my sbc edelbrock performer rpm heads!

I´ll have my dad run it through and post what the program says for max power. You´ll probably have a couple of real-world tweeks to what it says.
 
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Discussion Starter · #22 ·
Remember to compare apples to apples. Your Chevy heads are probably tested at 28" of water. So 112 cfm @ 10" of water is 187 @ 28" of water. Stock cast iron Chevy heads with 1.94/1.50 valves only flow 118 intake and 85 exhaust, so they are not *great* compared to, let´s say, a stock Opel 2.2 head. Most aftermarket Chevy aluminum heads I´ve flowed are at about 130-140 cfm intake @ 10" of water. A 2.2 or 2.4 head can be modified to flow 145-148 cfm with smaller valves than the Chevy.

If this sounds bad, remember that 302 Ford heads are pathetic in terms of airflow. 99 cfm intake and 62 exhaust!

Bob
 
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Discussion Starter · #23 ·
Yuck, that ford figure is terrible!

Here are the numbers for my heads.... 2.02/1.60 valves unported from the factory flow numbers are at 28":

Edl SBC Opel 1.9
In Ex In Ex
.1 67 58 57 47
.2 130 108 95 84
.3 183 144 144 127
.4 226 169 172 146
.5 229 175 182 159 (.475 peak 187)
.6 232 182

I think they´re pretty good for out of the box heads.
 

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I already have the answer to my own question.

Looks like Chris is starting the last of the cam billets for this run tomorrow.

Says the intro price of a complete set(Cam, Roller Lifters, Roller Rockers, Poly Locks, Stud Girdle and valve springs) is 1150.00

Cam and lifters only is 750.00

Whom else is planning on getting the rollers?
 

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Nope. Spoke with Chris last week, they 'should' be on their way to us by now.
 

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I spoke with Chris this morning. The rockers are done, I don't know about the cams but he is having to re-make the poly locks. He specified the wrong thread. He says they'll ship this week...we'll see. Same thing happened with the rocker bodies, except it was a wrong hole size. I'm really suprised he didn't do a quick prototype run. To each his own...

-Travis
 

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Yea, especially since I supplied him with a new rocker stud and one of my old design rocker arms.....it was right there in front of him. I spoke with him yesterday and he asked me about the thread pitch ironically....guess he realized at that point it was wrong. Also said he was shipping my cams out yesterday (only mine....there was another dimensional error which I said I'd correct myself rather than continue to wait). We'll see on that one.

Bob
 

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I got this picture e-mailed to me from Cam Effects. So it looks like we are nearing completion of the roller rocker arms and roller cams/lifters.

Bob
 

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Yes, they're being 're-made' with a few upgrades (stronger). Otherwise, they're the same design and geometry. Cam Effects is also making a few extra sets of 'polylocks' for me (to use with stock rockers on my ITB car), and I sent them my blueprint for my stud girdle design too, which they said they wanted to produce.

Bob
 

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I had a voice mail from Chris this morning. He doesn't have the poly locks yet. He expects them today....

-Travis
 

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I just got off the phone with Chris.....Sigh:(

The poly locks which were only to be oiled as of last week are now getting zinc plated. He dropped the stud girdles off at the anodizer today. They *might* be done tomorrow.

He did however note that he had already shipped 5 cam kits out to RallyBob. He didn't say when....

Argh! :mad:

-Travis
 

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I got my 5 cam kits from Cam Effects today. Awesome looking lifters, I can't wait to try them out. They're VERY lightweight and cannot rotate by design...cool stuff. They also sent me a sample of the revised roller rocker arms, and a lifter lash cap and locknut for the same, plus a sample valve spring for the roller cam, which I must check for fit and pressure.

Don't know when I'll get around to installing the first cam for evaluation, it's going into a friend's 2.5 litre but he's two states away and my schedule is tight. The head needs to be removed for machining to fit the lifters, plus installation of the new springs and new retainers. Earliest will be at the end of October, because of my schedule. I'll keep the forum informed.

Bob
 

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RallyBob said:


The head needs to be removed for machining to fit the lifters, plus installation of the new springs and new retainers
Bob
RallyBob,

I notice that you haven't listed enlarging the valve notches in the pistons. Have you already determined that isn't necessary? If yes, how? When I was initially considering a roller cam I had asked Chris for TDC cam lift info based on a given lobe separation and install position of the cam. For some reason he couldn't get that from his grinder. Struck me as odd since his business is roller cams and this would affect every cam he has sold.... I've had no problem getting this info from other grinders

-Travis
 

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All the engines that I'm installing roller cams into have custom forged pistons already in them. When I spec pistons for myself, I always figure a 'worst-case scenario' and have the valve reliefs made for ridiculous cam profiles (see, I know myself by now). So, in my case at least, the valve reliefs are essentially a non-issue. However, in other people's cases, this will have to be carefully checked and possibly corrected, but this is no different than installing a 'hot' cam in any engine. I WILL check for clearance, but only for peace of mind.

Another thing to consider is that all of the roller cams I ordered are for engines with more stroke than a 1.9 or 2.0. One engine is a 2.2 (3.05" stroke), another is a 2.3 (same stroke), two different 2.5 litre engines (3.346"), and a 2.7 litre (3.596" stroke). With a longer stroke, piston speed increases substantially, so piston acceleration away from TDC is faster, and valve clearance increases.

The cam for my 2.3 litre hillclimb engine is ridiculous, you should see it! It specs out at .571" intake lift, .560" exhaust lift, with 262 degrees intake duration @ .050" and 266 degrees exhaust duration @ .050".....the damn lobe is nearly flush with the bearing journal, and it is basically an oval! In fact, a relatively mild roller profile for a street engine (.490" lift and 245 duration @ .050") has a larger appearance than a solid lifter full road-race camshaft, the solid lifter cam has a far more pointed lobe than the street roller cam. Much more lift area 'under the curve'.

Bob
 

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Not much has changed since I posted status to the opeltuners list 1-1/2 weeks ago(this list was down at the time).

to recap:

I received the rockers, lash caps, poly locks and stud girdle. I found a few assembly issues which required a little adjusting. The lash caps don't fit on the solid lifters. The hole in the center of the trunion is too small to fit over the rocker stud(previously found by Bob). He didn't have any valve cover spacers made.

As of last Tuesday Chris was working on having new lash caps and valve cover spacers made. He was hoping to have them ready in a 'couple days'.

On the up side, it does appear that once the issues are worked out we're going to have some pretty decent parts and at a reasonable price...

-Travis
 

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Cool do you have a head picked out that you plan to install the stuff on?


do you have flow numbers on the head?
and cam specs

maybe someone could run them on one of those computer programs



i cant wait for your report

thanks
Davegt74
 
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