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Cam gurus, I need advice

General engine tech -- Drag Racing to Circle Track

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skinny z
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Re: Cam gurus, I need advice

Post by skinny z »

smokie wrote: Sat Jan 21, 2023 9:36 pm I have a comp cams XR294HR hydraulic roller in it, still on the engine stand. .
KnightEngines wrote: Mon Jan 23, 2023 1:35 am
Holy shit, I almost completely agree with F-BIRD!!
Except the dual plane thing, that's a no from me, leave the Vic jnr.
1.6 intake rockers & looser converter & you'll be happy.
CamKing wrote: Sun Jan 22, 2023 11:16 am
That cam will make peak HP at 6,400-6,500rpm.
If that's where you want to make peak power, then run it.

Usually, with a 3,000 stall, I put peak HP at 6,000-6,200rpm.
So one is swapping a cam to suit the existing converter and the other is getting a converter to suit the cam.

Which is it?
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Re: Cam gurus, I need advice

Post by CamKing »

skinny z wrote: Mon Jan 23, 2023 9:46 am
So one is swapping a cam to suit the existing converter and the other is getting a converter to suit the cam.

Which is it?
That's up to the OP to decide.
If he wants to turn it 6,500+RPM, keep the Comp cam, and change the converter.
If he wants to only turn it to 6,000-6,200, and be more street friendly, keep the converter, and change the cam.
Mike Jones
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jonescams@bellsouth.net
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Jones Cam Designs' HotPass Vendors Forum: viewforum.php?f=44
(704)489-2449
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Re: Cam gurus, I need advice

Post by CamKing »

smokie wrote: Sun Jan 22, 2023 1:42 pm Thanks Mike, can I ask why the 110 lsa verses a 106 or 108?
The shorter duration cam on the wider lobe center(106 ICL-114 ECL) will have a flatter torque curve, and still hold on to the top-end power.
Mike Jones
Jones Cam Designs

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jonescams@bellsouth.net
http://www.jonescams.com
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Orr89rocz
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Re: Cam gurus, I need advice

Post by Orr89rocz »

Wont see a big difference in the cams. Nothing noticeable on the street

I would run a different valvespring tho imo. A smaller diameter double with 150 seat closer to 375-400 open imo or so. Maybe even 165 seat. Or a conical or beehive, you can get away with less pressure there

242 deg is pretty hot in a 383. Imo i wouldnt run less than 3600 stall. 3000 is fine for a driver but you’re leaving track times on the table and be more fun from a throttle punch with more
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Re: Cam gurus, I need advice

Post by rfoll »

I didn't see anything about usage. A description of the car etc, but is it a daily driver, or a weekend warrior? Are you looking for best HP or drivability.
So much to do, so little time...
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Re: Cam gurus, I need advice

Post by smokie »

Weekend warrior, I don't care about gas mileage or vacuum for brakes. It might get driven a couple times a month and hauled to the track. No heater box or a/c. I just want to run on 93 pump gas.
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Re: Cam gurus, I need advice

Post by skinny z »

CamKing wrote: Mon Jan 23, 2023 10:54 am
skinny z wrote: Mon Jan 23, 2023 9:46 am
So one is swapping a cam to suit the existing converter and the other is getting a converter to suit the cam.

Which is it?
That's up to the OP to decide.
If he wants to turn it 6,500+RPM, keep the Comp cam, and change the converter.
If he wants to only turn it to 6,000-6,200, and be more street friendly, keep the converter, and change the cam.
Are those peak HP RPMs being discussed or RPM redline past peak? That is to say, peak HP at 6000 and shift at 6500 as an example for the smaller cam?
Conversely, the COMP 294 makes peak HP at 6500 and the shift is further up the range. (Talking about a drag race deal here).
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Re: Cam gurus, I need advice

Post by CamKing »

skinny z wrote: Mon Jan 23, 2023 1:49 pm
CamKing wrote: Mon Jan 23, 2023 10:54 am
skinny z wrote: Mon Jan 23, 2023 9:46 am
So one is swapping a cam to suit the existing converter and the other is getting a converter to suit the cam.

Which is it?
That's up to the OP to decide.
If he wants to turn it 6,500+RPM, keep the Comp cam, and change the converter.
If he wants to only turn it to 6,000-6,200, and be more street friendly, keep the converter, and change the cam.
Are those peak HP RPMs being discussed or RPM redline past peak? That is to say, peak HP at 6000 and shift at 6500 as an example for the smaller cam?
Conversely, the COMP 294 makes peak HP at 6500 and the shift is further up the range. (Talking about a drag race deal here).
Those are peak HP rpm's I gave. Shift point should be about 400-500rpm higher.
Mike Jones
Jones Cam Designs

Denver, NC
jonescams@bellsouth.net
http://www.jonescams.com
Jones Cam Designs' HotPass Vendors Forum: viewforum.php?f=44
(704)489-2449
skinny z
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Re: Cam gurus, I need advice

Post by skinny z »

CamKing wrote: Mon Jan 23, 2023 2:18 pm
skinny z wrote: Mon Jan 23, 2023 1:49 pm
CamKing wrote: Mon Jan 23, 2023 10:54 am

That's up to the OP to decide.
If he wants to turn it 6,500+RPM, keep the Comp cam, and change the converter.
If he wants to only turn it to 6,000-6,200, and be more street friendly, keep the converter, and change the cam.
Are those peak HP RPMs being discussed or RPM redline past peak? That is to say, peak HP at 6000 and shift at 6500 as an example for the smaller cam?
Conversely, the COMP 294 makes peak HP at 6500 and the shift is further up the range. (Talking about a drag race deal here).
Those are peak HP rpm's I gave. Shift point should be about 400-500rpm higher.
That's what I figured Mike.
Thanks for clearing that up.
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Re: Cam gurus, I need advice

Post by smokie »

Comp cams advertises that cam for 3,000-6100 rpm. I thought that sounded off myself. I also got the valve springs they recommend for the cam. I've heard several say comp is a little conservative on their spring recommendation on their roller cams.
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Re: Cam gurus, I need advice

Post by Tom68 »

smokie wrote: Mon Jan 23, 2023 4:50 pm I've heard several say comp is a little conservative on their spring recommendation on their roller cams.

You need to confirm the load at height to. SAE allows for a percentage of error on the claimed spring rate, I've had a set of comp springs that were on the bottom of that tolerance.
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Re: Cam gurus, I need advice

Post by skinny z »

What's the take on a beehive/conical spring as opposed to the traditional spring or dual spring?
It looks to be common knowledge that the beehive can do more with less due to it's reduced mass. Including the retainer.
The XR288HR I've used across a couple of 350's used COMP's 26918 with no issues to 7k. (288/294, 236/242, 110, .347/.360 lobe).
That spring has nearly identical specs to PAC's 1219.
125 @ 1.800.
367 @ 1.150.
372 lbs./in.
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Re: Cam gurus, I need advice

Post by F-BIRD'88 »

You have a very good moderate street strip Nitrous injection platform with the 3.73's. And the Comp cam you got.
Yes you can tweek the valve springs for better high rpm perf.
Can share a few thingies on that to get there with this
car if you want. PM me if interested in that.
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Re: Cam gurus, I need advice

Post by Orr89rocz »

smokie wrote: Mon Jan 23, 2023 4:50 pm Comp cams advertises that cam for 3,000-6100 rpm. I thought that sounded off myself. I also got the valve springs they recommend for the cam. I've heard several say comp is a little conservative on their spring recommendation on their roller cams.
Probably cuz thats where it floats with their springs
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Re: Cam gurus, I need advice

Post by smokie »

Orr89rocz wrote: Tue Jan 24, 2023 8:20 am Probably cuz thats where it floats with their springs
LMFAO probably lol
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