Optima Challenge update - chassis dyno and track video

[Steve1968LS2]

Well it's been a couple weeks and I still can't believe we actually won. But, the best part was getting to see so many killer rides getting the snot beat out of them.

It was also great meeting new people like James and seeing new cars like the One Lap Camaro and the Motivator (don't worry Larry, you can run it next year). Was also nice to see some cars again like Fuel and killer rides by air ride and DSE. It was just plain FUN!

I drove the '68 out to Vegas from CA and it was running badly.. it was surging and just not happy. I attributed this to the fact we wern't able to tune the car before leaving.

So the car held together and David and Mary beat it to death just like I told them to. Besides a problem with oil blowing out the breather all went well. We now know what suspension stuff needs to be done for next year. The car has a LOT left in it.

So today I finally drive the car over to Westech for some chassis dyno tuning. So we strap it down and make a baseline pull.



Wow, those are some pretty weak numbers for a 402.. we continue to fiddle with the tune and even though it shows lean it smells rich. After a bit Ernie notices an anomoly on left side O2 sensor. We check the plugs and find this:



Number 5 cylinder.. the fuel we smelt was gas just washing though that cylinder since there was no fire. I drove to Nevada, and we ran in the challenge on seven cylinders. doh!

So, we tossed in a new plug and picked up 70 hp and tq to the wheels... after a bit of tuning we maxed out at 474rwtq and 481rwhp. A HUGE improvement over what we had. The car is nuts to drive now, it's like I added a blower. lol



The plug must of been broken when we lifted the engine to change the pan. I kind of feel stupid for not checking it, but it didn't run THAT bad.. not like it was on seven.

Monday we finish part throttle and idle tuning and then we change the oil. After reviewing the video I can tell I need an oil cooler. By the third lap my oil tems were up from 200 to almost 300 degrees. Glad I'm running synthetic Torco.

Here's a video of the dyno pull. It's crappy since I took it with a cheepo camera.



I'm downloading a low res video of three laps around the Spring Mountain track. Will post when it's done.

Already planning a host of improvements for next year. Mabey I will actually think to put a decent alignment in the car this time. lol

[Steve1968LS2]

Spring Moutain raceway video - In Car Mount.

I'm working on getting a high-res online. It's cool to be able to read the MPH on the Racepak. He was almost hitting 100mph in some of the sweepers.

Also, I dig the view in the rearview mirrow. Especially at the beginning when he pulls away from the ZR1.

[James OLC]

That's amazing Steve. We spent a bunch of time at ATS - including your increadible 2x4 shots heard around the world (or at least the parking lot) - and it sure didn't sound like it had a miss... 20% more power... nice.

*awesome video* - two weeks late but great!
I love that you can hear Tyler wimpering softly as David comes around 10.
I also recognized those sounds in 7 on the recon lap.

Great stuff.

[David Pozzi]

Wow Steve!
I thought it should have had more power but thought it was due to the tune. I guess the gearing will have to be way different next time, or a shift to 4th in two more places will be needed. The brakes will get more use too!

You can hear the tires squealing a lot, I don't remember them being that loud, but I was focused on driving at the time.
I gave Tyler a thumbs up every time I made a successful shift. Had a lot of trouble with that, especially on the front straight on the warmup lap. I had to shift very slowly.
David

[bulldog19]

Wow!! Awesome video, car sounds awesome at speed. Thanks for sharing. Amazing on 7-cylinders, bad tune and no race alignment Team Penny won. Everyone will be gunning for you guys and gal big time next year!

[BMF Machine]

So, we tossed in a new plug and picked up 70 hp and tq to the wheels... after a bit of tuning we maxed out at 474rwtq and 481rwhp. A HUGE improvement over what we had. The car is nuts to drive now, it's like I added a blower. lol

[Larry Callahan]

Wow, won it on 7 cyl! Can't imagine on all 8.

Next year we will have to drive up together. I can't wait to run MotiV8r there.

[Bow Tie 67]

Steve or David,

Do you remember the air pressure ran in the front and rear tires?

Matt

[Steve1968LS2]

Wow Steve!
I thought it should have had more power but thought it was due to the tune. I guess the gearing will have to be way different next time, or a shift to 4th in two more places will be needed. The brakes will get more use too!

You can hear the tires squealing a lot, I don't remember them being that loud, but I was focused on driving at the time.
David

We raised the rev limiter from 6,600 to 7,000.. so that should help. Also remember that we had a stock alignment. Need to come up with a routing for an oil cooler.

Wow, won it on 7 cyl! Can't imagine on all 8.
Next year we will have to drive up together. I can't wait to run MotiV8r there.

Sounds like a plan! We will need a third "chase car" to shoot video and stills.

[Steve1968LS2]

Steve or David,

Do you remember the air pressure ran in the front and rear tires?

Matt

I think it was 38 or 39. We dropped out 6psi on the autocross.

[Restomod]

Really cool Steve I bet everyone wishes they could get 70+ hp just by changing the plugs!!! LOL

[monza]

Great track vid! Thanks for posting that.

Next year I'll have to break two spark plugs!!! Never thought it would run so well on 7.

[David Pozzi]

That's one of those special "Split Fire" plugs!

Steve,
If your left hand radiator tank is large enough, you can put a heat exchanger inside it to cool your oil.
David

[Mike Norris]

Very cool Steve, nice when you find one issue that clears up several questions. Really nice when it is a simple fix. I saw the O2's were not very balanced when I was scanning the data and making a few small changes at SEMA and really wish we had time to go through everything. Would have been interesting to see.

Talk to you soon.

Mike Norris