I wounted to build a roller whin I started out did not have the cash thin. (but I do know) my mottor runs good no probs. you did a dyno for me with my 282solid (comp) would you please do a dyno with thar cam and the cc xr282 hr and a cam that you think would be right for my combo. my car s about 3800lb. first is about 411 gear and I have a lock up switch on my 3500 hughs in fourth gear only springs: double good for 600 lift and seats about 135 or 140 car run beat 12.72@106.89 and 1.76 60 ft curb has 78 front and 80 back car started out @13.20 and best 12.72 with fine tunning and jet changes 32* total timming if you would post all three cams thanks I value your opinion. (check sig)

What kind of tires? What are your incremental times? I would think your 60' time can be at least a tenth quicker, mid-1.6 or so. How many mph do you gain in the last eighth? What kind of exhaust system are you running?

In my simulations I found a couple of things:

1. I really have to choke the motor off to get the mph below 110 in a 3800# car. I add more accessories, smaller mufflers, etc.

2. There was little difference in e.t between the flat tappet and a similar solid or hydraulic roller cam. I varied the duration from 225° to 245° with minor effects on the time slip. The power curve is different, but the e.t.'s don't seem to vary much. You don't get to use much of what you gain on the top end, and what you lose on the bottom end bites you every time you shift.

With a 3.42 rear, 10% slip and a 26" tire you are running about 5200 rpm in the lights. You spend over half your time on the track accelerating from 4000 to 5000 rpm, so you need to concentrate on power in that area. You spend the last 900' of the track in high gear between 4000 and 5200 rpm.

first off I had a blown head gasket so I saw a good cause to get a cam ,so I did today . I ordered a cam from lunati after talking to UDHarold I got the 280/284f10 soild 247/251 @ 50 159/152 @ 200 with a 560/565 lift with 1/6 rockers so could you dyno. that cam for me please? could not find my best time slip but I found my second best.
1.786----60ft
5.188----330ft
8.106----1/8et
84.16---1/8 mile
10.63----1000et
12.77-----1/4et
105.31----1/4mph
second Iused old pair dirt track tires Hoosier I think 265 60s but I will check on the size (could not realy get good traction spun about 10 ft befor locking up) I do have traction bars and sub-frams.
third Iam running American Thounder with 2.1/2 pipe delta flow 50s headers Hooker Competition with 3" collectors .

Specification 265 / 60-15
Diameter 27.5 699
Radius 13.8 349.5
Sidewall Height 6.3 159
Circumference 86.5 2196
Revolutions / Mile 732.9
Revolutions / Km 455.4

Very interesting. I put in the new tire height and made a pass with the Comp 282S - 12.31 @ 109.86, 5159 rpm in the lights

Installed the Lunati cam at 106°, gained 12 peak horsepower at 6000, lost 3#ft peak torque @ 4500, lost 16#ft average torque from 2000-6000, converter stall speed dropped 120 rpm, elapsed time was 12.31 @ 109.83, 5158 rpm in the lights. Seems you weren't able to take advantage of the 12 horses because you didn't get there.

ONovakind67,

Luckily for me, a computer simulation has not yet really won a race.
My prediction is .1 to maybe .2 in the quarter. The CC 282S is 142° at .200, the 280/284 is 159°/162°. This is a lot of torque and BHP in the real world.

UDHarold

Thanks alot onovakind67 for your time in this quest and all the other times that you helped.
Thanks UDHarold for the time you gave me on the phone today and also is their anyway I could get a timing chart on that cam? graemlins/beers.gif

Harold,

You're absolutely right, simulation has never won a race or made any horsepower. I hope his motor really likes your cam and picks up a few tenths, it just didn't come out that way on paper. He asked for an assessment and I told him what came out.
One of the difficulties I have with simulation is matching the performance to the car. Here's a pretty stout motor with a 107 mph trap speed where I would expect something in the 115 mph range. As mentioned above I add accessories and mufflers in an effort to get the real trap speed. This is possibly not the best scenario for a bigger cam.
If I rehash the chassis with some 4.11 gears and slicks, use a converter to fit the cam, open up the 40" custom headers and let the computer shift gears, there is indeed a large gain using your cam, about .27 seconds and 3 mph.

Comp 282S - 11.33 @ 115.10, 1.50 60' time
UD280/284 - 11.06 @ 118.23, 1.48 60' time.