i forgot to mention that I have this combination (JR Motorsports/Holley SystMAX 2) going together at a shop on the west coast. Car Car Craft Magazine is photographing the assembly and the dyno pull so it can be feature in their magazine. Won't be out for some time. After that the engine is slated to be used for 4 long days of dyno work testing carburetors.

If anyone is interested I will get them to fax the dyno sheets to me so I can post the dyno numbers.

AFTER SHARK, you certainly have given me food for thought, would you care to E mail me 'off register' so we can discuss exactly what you do, what i need and costs involved ?

There is obviously a lot of options for me to choose from and i would like to keep the work i have to do to a minimum as i am spending a lot of time on my Jaguar project, my Vette was meant to be a 'Running Restoration' but has turned out to be me restore than Run



And a big thank you to all who have responded, hopefully there are also others who can add 'options' to this thread.

Ok, got the dyno result from the combination above.

Bottom End: 355 CID JR Motorsports Short block w/30142 Lunati Cam

Top End: Holley SysteMAX II Kit (I had them run a different cam, but cam in kit will give almost same results) 300-503-1

Carb: 0-4779
91 Octane / 36 Deg Total Timing

I'm always amazed by this combination and how little money it costs to put it together. So here are the Results

Speed Torque Power
2500 341.9 162.7
2600 356.7 176.6
2700 373.7 192.1
2800 388.8 207.3
2900 400 220.8
3000 407.8 232.9
3100 412.9 243.7
3200 415.4 253.1
3300 417 262
3400 418.3 270.8
3500 418 278.5
3600 416.8 285.7
3700 415.2 292.5
3800 416.9 301.6
3900 419.9 311.8
4000 424 322.9
4100 426.7 333.1
4200 428.6 342.8
4300 428.4 350.7
4400 426.3 357.1
4500 422.8 362.3
4600 420.1 367.9
4700 417.8 373.9
4800 416.4 380.5
4900 414.3 386.5
5000 411.5 391.7
5100 408 396.2
5200 404.9 400.9
5300 401.2 404.9
5400 398.1 409.3
5500 393.3 411.9
5600 386.3 411.9
5700 377.4 409.6
5800 360.3 398.2

Average Torque: 405.51
Average Power: 320.77

Everyone know it takes torque to move you down the road. Never drops below 400 lb ft from 2900 all the way to 5300. Talk about flat. And check out the peak power number all the way to 5600. My type of engine, done on a budget.

Enjoy!

|UPDATED|8/19/2004 2:51:48 PM (AZT)|/UPDATED|

After Shark said: Ok, got the dyno result from the combination above.

very impressive

Very impressive indeed. What a great torque curve. You have a winning combination.

After Shark said: Ok, got the dyno result from the combination above.

I would like to run these numbers in desktop dyno and see what it shows.. this would give me a good comparison

the 350 .030 over is easy..

I couldnt find the specs on that cam though..

looked in the avenger cams, and both regular SB chevy links

used 750 carb

the holley website only gives airlow specs at .500 lift for the heads.. (this isnt achieved with the similar cam in the kit)

do you have a more complete set of airflow specs ?

the valves are canted.. are the port oval or rectangular ? valve sizes 2.02,1.60

I used 78.30 total combustion space for a comp of 10.29:1
(68cc chamber, 0.050 gasket thickness, 4.000 gasket bore, flat top piston, 0.00" down bore at TDC)

what type of exhaust ?

and the intake std flow, high flow, high torque

|UPDATED|8/20/2004 10:22:29 PM (AZT)|/UPDATED|

More detail is what you want. Well I will do my best.

The SysteMAX II kit comes with a Lunati Cam P/N 07104. We didn't use this cam in the combo above, but here are the specs. There is nothing wrong with the cam it performs very well. Its just the Lunati 30142 cam has a slightly more agressive ramp speed that you can't actually see on any numbers chart.

Specs on the 07104 cam:
235/245 @.050
.507/.534 Lift @.050
.338/.356 @ Lobe
112 Lobe Sep
108 C/L
9.5BTC 45.5ABC 58.5BBC 6.5ATC

Specs on the 30142 Cam
235/240 @ .050
.490/.490 @ .050
.327/.327 @ Lobe
112 Lobe Sep
108 C/L
9.5BTC 45.5ABC 56BBC 4ATC

Head Info:
2.02 Intake
1.60 Exhaust
20 Deg Valve Angle
Rect Ports
68cc Comb. Chamber
Straight Plug
3/8" Rocker Stud

Head Flow Numbers:
Intake
.100 / 61.3
.200 / 124.0
.300 / 179.5
.400 / 219.8
.500 / 227.7
.600 / 231.7

Exhaust
.100 / 55.2
.200 / 91.4
.300 / 121.9
.400 / 145.7
.500 / 161.7
.600 / 173.7

Engine Specs on the 355 JR Motorsports Engine
350 / .30 over = 355 CID, Final Bore 4.030
If memory serves me correctly this is a zero deck short block
Flat Top Cast Pistons Four Valve Pockets
64cc heads will yield 9.7 compression
6cc more comb. Chamber will yield a 8.6 compression.
Our final compression comes in at 9.5:1

Gasket Info:
Used Felpro 1003 Head Gasket
4.166 Bore .041 Compressed 9.1cc Volume
JR figures compression on their short blocks using a 9.3cc Gasket area.

Headers & Exhaust:
Hooker 1-5/8” long tube
We don’t run mufflers on the Dyno.

Intake:
Holley Street Dominator Dual Plane P/N 300-36
Just a little History…..the Holley street Dominator intakes were designed with the help of, you guessed it, Zora Arkus-Duntov. Very few intakes can match the power and RPM range that this intake makes. Only the performer RPM cam match it.

Hope this info is helpful.

thats exactly what i was looking for..

im gonna run the software against your real dyno results and compare..

thanks

Let me know how it turns out. I'd be curious to know if the software is accurate. Although it will probably be off because it can't compensate for air/fuel ratio and other variables like water, oil and air temp.

between 11% high on the low end (2500) and 6% high in the high middle (5000)

to be as accurate as possible I really need the seat to seat specs also on the 30142 cam..

check em out and see if i guessed them right.

but here is the report

http://direclynx.net/~cthulhu/corvette/misc/Aftershark_test.pdf