Dyno Tunig Tips?

[ullose2]

I know this is a little long but here goes....

I was considering dyno tuning my motor as I have never been to the track, and I dont feel that Im experienced enough to do it by the seat of my pants. I was wondering if I posted the specs of the car if you guys could give me a few pointers as far as tuning goes. I dont have much experience tuning,and this is my first car. The car seems to be running really rich so I will try jetting, and I was also going to try changing the spring combo in the dist. for a little more timing. Is there anything else you guys could recomend to make the most of the dyno time. Is 275/hour a good rate for a chassis dyno? I really, REALLY appreciate your help. Anyways heres the combo.

Engine:
- .030 350 , Scat crank , Eagle rods , JE 10.1 pistons (when we checked the actual compression I think it was 9.85:1)

- Lunati Cam (hyd. lifters) .490/.490 int./exh. lift , 292/297 int./exh. dur. 112 deg. lobe separation

- Holley 20 deg. alum heads 2.02/1.60 int./exh.

-Harlan Sharpe 1.5 roller rocker

-Holley dual plane intake

-Holley 750 double pumper, mechanical feul pump w/ holley regulator pressure is set at 6 psi.

-Flowtech tri-y headers 1 5/8 in. primaries, Flowmaster 40 series mufflers, 2.5 in exhaust

-Ignition MSD Pro-Billet dist. mech advance MSD 6A box Blaster 2 coil 8.5mm super conductor wires

-trans th350 , 2400 rpm stall , Moser 12 bolt 3.42 gear, tru-trac diff.

These are all the specs of the car i could remember off the top of my head. If you need to know anything else I will find out and post. Anyways, thanks again.

Heath

[ullose2]

BTW, sorry I wrote a book for you guys. I didnt realize it was that long. :idea:

[DC454]

Is the $275 per hour you doing the tuning or them? Do they include a wideband? Are there any other dyno's in your area to compare prices?Try to get a decent street tune on the carb to try to minimize your dollars spent at the dyno. If your plugs are black, try to jet down your carb. The 750 DP sounds a little big for you setup. The dyno can be a great help to sort out a new combo or to fine tune what you already have. It all depends on how many cubic dollars your willing to spend.

[Fuelie Fan]

$275 sounds a little steep to me...but I'm not from your neck of the woods so I also can't provide any alternatives, other than to make friends with somebody who's good at tuning carbs :)

[ullose2]

I thought the carb was alittle big too, but thats what Holley recommended. Oh, and it was 275 for 2 hours. Im sorry that was a typo. I think they said it was 50 more for the use of an Air/Feul meter. I dont really know anybody who can tune carbs, maybe I should start spending time at the strip, or maybe I should just show up at Bill Howells and beg him to help me. :worship: :help!: j/k

[Dandale]

Thats BS that they charge extra for A/f meter I would try to find ANYYYYYYYY body else

[GBodyGMachine]

I work at livernois motorsports in Dearborn Michigan. We charge 3 hours for a NA Engine tune. $120 an hour with an o2. We dont beleive in rushing the process. It can be tricky. I would recomend a dyno tune over the good ol Ass Dyno.
Before you start, make sure your timing is where you want it. I run about 34-36 total on my stroker motor.
Start by getting your idle mixture and vacuum correct. around 13.5. Start about 1 1/4 turns out on the idle mix screws.
Then move to tip in on the primary side. (Accel. Pump & cams) If there is a hesitation, you may need a different cam or differnt squirters. 30cc pumps should be fine for your engine.
Then cruise air/fuel. I like to see around 13.0. Move the jet sizes up or down accordingly. These jets are im the front metering block.
Then tip in to the secondary circuit.
Now accel in both circuits. around 12.5-13.0. Change the rear jets if you are not at the correct air/fuel ratio.
And finally WOT. I like to see around 12.5 at wide open. Rear jet change as well.

Holly usually puts 6.5 power valves in their carbs. These should be good for your cam.

Any questions, please ask.

JEff

[ullose2]

First of all thank you very much Jeff for the advice. The only questions I have right now are do I need to weld in bungs in my headers for the O2 sensors, or do they use the tail pipe, and is there a kit i could buy that has different squirters and pump cams or do these need to be purchased individually. I will look around and see if I can find a different facility. The prices I stated above were from Delk performance in Lebanon, TN. If anybody knows of a different facility anywhere in the middle or eastern TN area I would appreciate it.

[GBodyGMachine]

Depending on what kind of intake you run will determine where you weld your O2 bung. I usually put my O2 bungs on the drivers side of the exhaust system, right after the header collector. Its hard to weld to coated headers. If you have cats on the car, put the bung before the cats. I would focus on just the cam kit for now, if you cant get enough fuel through your squirters(still bogs on tip in) you can then get high flow squirters. Cam kit part number is holley 20-12.

Jeff

[Skip Fix]

That's about par for the "big" shops here like MTI, they add on for wide band!Timing and jetting should be played with, and logging AFR to hp. The "ideal" varies form motor to motor.

[ullose2]

Cool. thanks again for the info. I will try to post later on after I go to let you guys know how it went.


Heath