comp cams 292h cam kit? how is performance?
- Thread starter blackstallion12
- Start date
Once you install the bigger valves and do the machine work to the chambers to accomodate them, your 10.5 to 1 comp ratio will be much lower than you think. They had 54 ccc chambers from the factory, but that's going to change with the work to unshroud the bigger valves. Once you do all the work necessary to do what you want, you'll have damn near the cost of new heads invested.
all the work done on the heads is free!!! i have machine shop at my community college. even the valves, which i got used from a chevy kid at school. i already threaded and purchased screw in studs i just need the correct thread sealer. also deshrouding should only add about 2 cc max to dome. also rbohm suggested the use of the windsor jr heads on my application and im not sure that my build would be much different.... the only difference is that my hand porting wont be nearly as fine as the windsor jr heads and i have the 1.5 valves not 1.6. but with that said you gentlemen still think its to much for that small of displacement. sorry guys im VERY new to this site. i was just wondering how the power was. it was my fault for not putting specifics in my questions and answers... have you guys ran this cam before and if so how is the power out put of this unit... i am sorry if i have waisted your time.
If you're looking for the max in upper rpm horsepower the 292 would be the way to go. But if you really want a more streetable grind, the 270 would be a better choice. Bigger heads, bigger cam, bigger intake (as in single planes like a Vic Jr) Plus smaller displacement, all serve to move the powerband up in the rpm range. I've never actually run a 292H but the basics are the same. Comp's description of it's characteristics is really all you need to know how it's going to behave.
no waste of time. remember that there are no stupid questions, only stupid mistakes. we just want you to have the best possible combination you can afford to build, for what you want from the engine. i am happy that you are doing the work yourself, including doing some porting of the stock heads. on the intake side you mostly just need to clean up the ports, and match the gasket, and blend that back about 1/2-3/4" into the port. you also need to eliminate the sharp edges in the bowls, and narrow the valve guide as much as possible. the exhaust side is where you are going to get the most power from the stock heads. the ports can be made much larger than stock, again match the gasket and blend it back into the port, and clean up the bowl area. i would however recommend that you get a junk head and cut it up in a variety of ways so that you can see how thick or thin the port walls are and in what areas so you avoid breaking through the water jackets.
while i also have not used the 292h cam, i have used cams that are too big for the application, and found that low end torque was missing, and that made for a frustrating daily driver. when you build an engine, you are going to learn that you need to match the components to the rpm range you are going to use the engine in about 80% of the time. for the street this means in the 1000-5000 rpm range. you can fudge your choices a bit each way, for instance you choose an intake that works well in the 1000-5000 rpm range, but you select a cam that works well in the 1800-6200 rpm range, and still end up with a combination that makes power where you want it.
keep asking questions so you can learn these lessons the easy and inexpensive way, and build solid combinations from the start.
woodsnake
15 Year Member
If you want to enjoy the car at all, I think you'll enjoy the Comp 270 the most. Anything much more than that, and you will really need to start looking at rear end gears, stall speed, etc......
Also, you will still need to verify your valve train geometry, installed spring height, push rod length, blah blah blah.
Also, you will still need to verify your valve train geometry, installed spring height, push rod length, blah blah blah.
the cam suggests a rearend ratio of 410 or higher... i have 430 nine inch posi. also chevy valves are identical overall length and identical keeper hight as the stock fords.... i will check the installed spring hight. also this car is going to be mainly for strip use, pleasure, and aggressive driving. i have a 1960 ford f100 pickup for everyday use.
S-Car-Go
Member
Blkford nailed it. Go with a solid lifter cam. 19 yr old, 4.3, mostly strip? Why would you want to go hydrolic? Back in the day my DD 289 saw 7,000 every day. A couple of years ago I had custom SFT in my 331 similar to a 270S and it was totally streetable (and I handed a brand new vette his @ss from a rolling start). I pulled it when gas bounced off $5/gal in my area and I couldn't keep my foot out of it.
woodsnake
15 Year Member
So, you are familiar with setting up the valve train, and know what to look for with a wear pattern on your valve stems?
Most folks aren't all that up to speed. If you've already got it down, and it is a mostly strip/sometimes street car, then cam up! I was thinking you would want to drive the car to work a few days a week, or at least some street driving.
A 4.30 trac lok around town would be a hoot!
Not so much fun in commuter traffic, but a blast between stop lights.....
Most folks aren't all that up to speed. If you've already got it down, and it is a mostly strip/sometimes street car, then cam up! I was thinking you would want to drive the car to work a few days a week, or at least some street driving.
A 4.30 trac lok around town would be a hoot!
Not so much fun in commuter traffic, but a blast between stop lights.....
You just answered your own question here. 
If you wanted to build a motor that made all it's power "up top" why did you build a 331 ? And with 351W heads ? And a HP peak at 6500 ? A motor that makes all it's power "up top" (that's in the 3500-7500 rpm range in my book) is fun for about 30 minutes. A motor like your 331 (and mine as well) that "turns on" at 1500 and pulls to 6500-7000 is a lot more fun on the street. With the powerband you have, you could have just as easily had with a hyd. roller. Which is what I've got in my 331 (Ford Z303 w/1.7 rockers) It doesn't float the lifters till somewhere north of 7000, well after it's reached it's peak power.
brianj5600
Active Member
A solid flat will make more power than a hydraulic roller any day of the week. I would be very surprised if the Z cammed motor with canfield heads could put down more than 350rwhp.
not true at all. given the same specs, the roller cam will make more power due to less friction.
It might make more PEAK power, but the roller will make more power down low and up to that point. As for your HP "guestimate", that's just that, a "guesstimate"
I didn't build it to make peak HP. I built it to drive. Maybe someday I'll get a chance to dyno it and see the numbers. Until that point, I'm completely satisfied with it's output and street manners.
