924Board.org

924RACR · Posted: Tue Jan 25, 2022 6:16 am Post subject:

Cedric - maybe, if you have or can dig up some of that raw data for the sims, we can use it for others going forward... once we know what those parameters are!

Maybe if Chuck can provide his specs (or intended specs) for cams, we can wrap that into simulation, try one or two different header options. My fabricator has both the MSDS and Stahl headers, and so can provide those measurements when he has a moment, feed those in and use as a starting point...

Also, Chuck - since you have a dyno, just need a location - any thought to setting it up somewhere else, like at Hayes's place?? Though I understand your point about real-world data - just the simplicity of trying something out without a full install etc...
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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Cedric · Joined: 27 Aug 2004 Posts: 2830 Location: Sweden

MikeJinCO · Posted: Tue Jan 25, 2022 11:13 am Post subject:

Count me in also. I'm too far away to be much help but can make a contribution for dyno time. Probably should contact Hayes Lewis to see if he has some base line dyno data for an Hp motor.
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Mike

'67 MG Midget Dp
'71 Ocelot Dsr Kawasaki 1000(under rebuild)

924RACR · Posted: Tue Jan 25, 2022 10:34 pm Post subject:

May be options for setting up that dyno elsewhere; that said, if we can do most of the development in simulation, then verify on dyno - maybe then chassis dyno and track will suffice...

Talked to Hayes last night, he thinks he could well have much of the engine data needed for sim...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Mike9311 · Joined: 14 Dec 2004 Posts: 1798 Location: Chicago-ish

Is your head stock or ported? I am willing to donate as well. Hate that I missed that head flow 'pool' years back
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1980 931 since 1989
1981 Ideola 931 Club Sport
1982 931 Entwicklungsfahrzeug
1979 924 NA ohne 650 mit 471
1982 931 Red Resurrection - 951 IC
1982 931 parts car / resurrection?
1980 924 NA (R&D lightweight)
1982 931 wana-be GTR race car

924RACR · Posted: Wed Jan 26, 2022 1:34 am Post subject:

For HP Limit Prep aka Level 2, we are only allowed port-matching within 1" of the mating surface - same as IT prep.
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Cedric · Joined: 27 Aug 2004 Posts: 2830 Location: Sweden

So you can only work the port at 25mm from the surface gasket and inwards? What cam do you run? I ran many exhaust man simulations on the standard car, and it was very hard to find much with the standard cam, ports and intake, just a very few hp if i remember correctly, if even that. Its a bit hard to fully take advantage of the tuned scavenging effect when there is so little overlap to work with. The std manifold isnt that bad either, with the cam and intake length available in standard form. But vetter port data for my model would be very nice to have. Maybe i took it from an old magazine.
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1980 924 Turbo
www.instagram.com/garagecedric/

924RACR · Posted: Wed Jan 26, 2022 3:33 am Post subject:

So in the IT trim we've been running - yeah, stock cam, we can bump the timing a little bit that's all.

For the HP trim, cams can be done, so Chuck is working on that as I understand...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Fifty50Plus · Posted: Wed Jan 26, 2022 4:14 am Post subject:

Actually, I just got a call from Hayes saying that his chassis dyno shop has room for my engine dyno if I'm willing to loan it to them. I'm leaning in that direction since I'm too busy with customer 356 and 911 engines to devote any time to setting the Stuska up. Since this is sounding like a great collaborative effort, I'm in. I haven't told Hayes okay yet so maybe he will see it here.

As for cams, Hayes is the focal point with Dema Elgin for the cam that he has and the one made for me. Dema would like a bunch more used but good 924 cams in order to fill his oven after he grinds them. I'm headed out to my shop shortly to see how many good ones I can provide. I would like at least one more for myself, Matti Vilkillen (a local racer friend of Hayes and myself) wants one (building an H Prod 924), Ed Moore wants one plus probably Hayes. How many others on this thread want one?
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1979 924 NA race car H-Prod SCCA
1982 924 NA race car - Sold
1981 924 Turbo sold
1982 924 Turbo sold
1972 911 E race car - traded for Cayenne Diesel
1975 914 1.8 Building for H-Prod SCCA

924RACR · Posted: Wed Jan 26, 2022 7:18 am Post subject:

Yeah, I got cams, and getting in on the Elgin buy sounds good to me. Just have to dig 'em out of the stack and box/ship.

Any guidelines on what is a good useable core?
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Fifty50Plus · Posted: Wed Jan 26, 2022 8:16 am Post subject:

I just looked in my stash and have 3 NAs, two with no obvious wear or pitting on the lobes & one with several lobes obviously pitted and worn down. I also found another NA cam that is marked Elgin (lobes aren't as pronounced as the new Elgin H-Prod cam) but it has been turned down and widened. Hmmmm...I wonder when/where this came from.
I also have three NA engines that haven't been taken apart yet so I might have some other good cam cores.
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1979 924 NA race car H-Prod SCCA
1982 924 NA race car - Sold
1981 924 Turbo sold
1982 924 Turbo sold
1972 911 E race car - traded for Cayenne Diesel
1975 914 1.8 Building for H-Prod SCCA

MikeJinCO · Posted: Thu Jan 27, 2022 2:57 pm Post subject:

Is somebody doing a group buy on the new Elgin cam? I'd like in I have one good core.
_________________
Mike

'67 MG Midget Dp
'71 Ocelot Dsr Kawasaki 1000(under rebuild)

Fifty50Plus · Posted: Fri Jan 28, 2022 2:48 am Post subject:

Mike,
Hayes worked with Demi Elgin to develop an H-Prod cam for his Runoffs effort last fall. So far there are 2 cams but a bunch of us want some more. Demi grinds the core cams and then heat treats them in an oven. He told us that he'd like enough cams to fill his oven (unknown quantity) if we ask for more to be ground. So far we have at least 4 folks that want at least one. If you want one. look for a good core in your stash and let us (Hayes) know that you are in.
_________________
1979 924 NA race car H-Prod SCCA
1982 924 NA race car - Sold
1981 924 Turbo sold
1982 924 Turbo sold
1972 911 E race car - traded for Cayenne Diesel
1975 914 1.8 Building for H-Prod SCCA

MikeJinCO · Posted: Fri Jan 28, 2022 3:51 am Post subject:

I'm in, emailed Hayes. With JE now being 10-12 weeks out and 12-1 87mm pistons not on order yet I predicting July for my 931 based motor.I
_________________
Mike

'67 MG Midget Dp
'71 Ocelot Dsr Kawasaki 1000(under rebuild)

hayeslewis · Joined: 21 Aug 2011 Posts: 74 Location: Alexandria, VA

If any one wants to run a sim on the engine here's some data on the Elgin cam and the stock head. At the .010 intake and .012" exhaust gross lift is .415 and .413

I don't know why these photo links wont work but the cam and head flow data is pictured

https://www.amazon.com/photos/shared/YIL7WIiIQSuSOjNmBXLmJA.vbYKeTtDdiFVWfPS8JAX_h

https://www.amazon.com/photos/shared/Ajqwq_MiQRGSosk3rZC8nQ.Y2cpw73F4tOJRuQjPxhkq9

I ran this data on Desktop Dyno5 and got some interesting results. The program thinks the throttle body is the restriction (at least with this cam)
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Hayes Lewis
1979 924 HP
1979 924 ITB/HP???
2007 Armada
2013 Hyundai Elantra
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