[RTCheveLLe]

I want to know if anyone is running the comp cam 280H in a BBC. I am wondering how it performs.

 

[malibu man]

My best guess is you might come up with something if you run a search on it.

 

[GRN69CHV]

I've know a few that have ran it. Decent grind, with a good lope to it and around 12" of vac at idle. A safe cam, in that the ramps are not so quick to make it prone to wear.

 

[Whittaker]

I have one in my 489, Pretty small for me but it does OK. It would be better in a 454. I would look at Lunatis Voodoo cam IMO.

 

[Hi-po SS 454]

I'm running that cam at this time in a 454 60 0ver. Idles at 750 nicely. Its a medium came with 420 lift, but has a killer agressive idle that you would think was lot bigger cam. Comp. Cam claims your stock converter is OK. But I would say it would not hurt to increase stall. Next year I will move on, thinking more into the mechanicle cam area. If your looking for a medium performace cam the Magnum 280 is one of them...Comp. Cams catalog shows operating range from 2000 to 6000 RPM with the correct springs. They say have at keast 9.1 compression..In a 396 or 402 its a little more agressive, you need stall and lower gears with a rough idle...

 

[RTCheveLLe]

Here are the specs of the motor that the 280H would go into.

454 bored to 468
around 9:1 compression
781 oval ports assuming stock valves
Edelbrock performer rpm
Holley 780cfm
M-21
3:73 gears
Heddman headers (1 3/4" primarys)

How would this combo perform?
Could you ran the stock valve springs?

THANKS

 

[Hi-po SS 454]

You neeed to use the comp cams 911 valve spring set. You don't want to use the stock springs. Also if your running stock flat top pistons with the 781 heads I doubt you have 9.1 compression, more like 8.1
The cam should run good, its not a ballsout cam but will get the job done a good street machine.

 

[Sandy]

I am running the Comp 280H in my 66 Beaumont.

10:1 compression, 99.5cc oval port cast iron heads with 0.095 dome forged piston. 2.19/1.88 valves

Cam works well with 2400 converter, 4.1 gear and vacuum secondary Holley 750. Although a 3000 might yield a bit better 60 ft time.

Shifts at 5000 and runs out the back at 6000 rpm.

Nice conservative low maintenance combination to get you into the mid 12's or better on pump gas.

Power brakes, power steering, heater, regular belt driven fan.

Would be interesting to run this engine/car combo with a 200R4. Nice low launch gear and overdrive to boot.

 

[Hi-po SS 454]

I am running the Comp 280H in my 66 Beaumont.

10:1 compression, 99.5cc oval port cast iron heads with 0.095 dome forged piston. 2.19/1.88 valves

Cam works well with 2400 converter, 4.1 gear and vacuum secondary Holley 750. Although a 3000 might yield a bit better 60 ft time.

Shifts at 5000 and runs out the back at 6000 rpm.

Nice conservative low maintenance combination to get you into the mid 12's or better on pump gas.

Power brakes, power steering, heater, regular belt driven fan.

Would be interesting to run this engine/car combo with a 200R4. Nice low launch gear and overdrive to boot.

Good info, sounds nice !!!! Sandy what about that 5000 shift kind of early or no ???

 

[Sandy]

I have tried shifting all the way up to 6000 and it doesn't make much difference. I ran the 12.42 shifting at 5000. Have had two passes that based on the 1000 ft time would have been 12.39 if run through but purposely slowed down to avoid breaking out.

At sea level and with a 3000 converter I think it would run 12 flat or better which is decent for what it very mild especially compared with the fast stuff we read about on this forum. My converter is probably the worst link in the powertrain. It is a "no name brand white box" and seems to slip around 12 percent on the top end. Would like to try a 3000 B&M Holeshot to get a bit less 60 ft and see if it tightens up on the top end. Would like to go through the traps closer to 5500 also.

Would be interesting to play with different axle like 3.7, a looser converter and a 200R4. This would maintain or improve the ET and allow for comfortable highway driving.

You have to understand this is a 12.5 second car/engine combo that works on the street and tweaking will make for small improvements measured in a few tenths, but low 12's is about it under ideal conditions.

If you wanna go 10 seconds like a lot of guys on this forum you need lotsa power.......like real lotsa power.

 

[Hi-po SS 454]

I have tried shifting all the way up to 6000 and it doesn't make much difference. I ran the 12.42 shifting at 5000. Have had two passes that based on the 1000 ft time would have been 12.39 if run through but purposely slowed down to avoid breaking out.

At sea level and with a 3000 converter I think it would run 12 flat or better which is decent for what it very mild especially compared with the fast stuff we read about on this forum.

Would be interesting to play with different axle like 3.7, a looser converter and a 200R4. This would maintain or improve the ET and allow for comfortable highway driving.

You have to understand this is a 12.5 second car/engine combo that works on the street and tweaking will make for small improvements measured in a few tenths, but low 12's is about it under ideal conditions.

If you wanna go 10 seconds like a lot of guys on this forum you need lotsa power.......like real lotsa power.

I'm looking to equal your times, at this time. So some additions and tweaking will be added before I take it out. Replacing axles etc.. I woulld say you have yours tweaked in the right fashion :thumbsup:

 

[GRN69CHV]

The 5000 RPM deal in a 454 is consistent with what I have seen in other big blocks with Chevy heads and this cam. The 396 motors will rev hard to about 5800, 427's to about 5500. Just from my own experience, a BBC stock head (even with bigger exhaust valves and mild port work) works good with a 240 @ .050 ( or more) exhaust lobe, especially the long stroke motors can really benefit from the added exh timing. Aftermarket heads - whole different story.

 

[mr 4 speed]

FYI
I shift my 454 @ 5200 1-2 and 5500 from 2-3
car runs its best at the track this way.