Dyno-Tune Shop, Seattle-Tacoma Area?

[Don W.]

I'm looking for a shop that can dyno tune my '69 427/390HP coupe. Any recommendations are appreciated. Thank you...Don

[Duke W.]

Re: Dyno-Tune Shop, Seattle-Tacoma Area?

You can find shops with Dynojet chassis dynos by going to their Web site and searching your zip code, however, I would doubt that any shop will understand what the ideal spark advance map is for your engine being as how most of the personel are probably younger than your car.

Dynojets are best because they are the most common and can be used to compare your engine's performance with others that were tested in other places at other times. Get the test files by email or disk, download the free analysis software from the Dynojet Web site, and you do your own analysis and have a digital record of your tests

Read the following presentation, and do your own "tune".

http://stlouisncrs.org/news_files/DukeWilliamsEngineTuningPerformance&EconomySeminar.pdf

You'll need to know what your OE spark advance map is, measure what it actually is on the car (It may have been changed over the years), buy the referenced spring kit and maybe a vacuum advance. The OE VAC on your engine should be a 12", but does it work, or had it been replaced with something else? If it's okay all you need is the spring kit.

Once you get it dialed in with road testing, a trip to the dyno is a good idea. You can try different total WOT spark advance values in the recommended range to optimize your engine's performance, and verify that the fuel mixture is in the proper ballpark for both cruise and WOT.

Dyno time is typically about $100-$150 per hour, and you can get a lot done if you have a good plan. Also, often car groups organize "dyno days" where you get two or three pulls for about forty bucks, which can be good for verifying a good SOTP feel from road testing and provide real numbers. If you could get enough guys in your chapter interested it would make a good chapter event.

If you email me I can return a dyno test plan to you that you can use as a template for your test plan.

Make sure you start the pulls from LESS THAN 1500, so you determine the full torque/power curves. The typical 3000 to 3500 start point that most dyno operators use doesn't tell you anything about where you spend 99 percent of your driving time, and determining the lower 80 and 90 percent torque bandwidth values is important to determining if you tune is optimized.

Your OE spark advance map is pretty good and should only require changing to full time vacuum advance, lighter centrifugal springs, and more initial advance assuming is hasn't been screwed up over the years, which is common.

You should also contact Scott Marzahl up in your area. (He's on the TDB.) Scott has recently dialed in his new "327 LT-1" in his '67 and is ready for dyno testing. He's also very knowledgeable about how to set up a vintage Corvette engine for maximum performance and fuel economy, being as how he just completed the job on his engine, with a little help from me.

It will be interesting to see who makes the most top end power, and I think I know the answer.

Duke

[Jim D.]

Re: Dyno-Tune Shop, Seattle-Tacoma Area?

Don, I sent you a PM with the info. you requested.

[Ronald W.]

Re: Dyno-Tune Shop, Seattle-Tacoma Area?

If you don't want to do it yourself contact Corvettes Of Auburn. Dan @ 253.939.3796