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Those of you with 03 /04 SSRs who need some encouragement and proof that 03 / 04 SSRs CAN be quick with some judicious mods, here's that proof.

The attached G-Tech graph of a run I did yesterday (11-17-05) is for a NATURALLY aspirated 03 / 04 SSR. No supercharger and no nitrous.

The Magancharger supercharger kit is in my opinion the best "bang for the buck" if you can, and want to, spring the $6000 to $7000 for the kit plus $800 to $1500 for installation, all at once.

But, if you want to move more slowly, the approach I took, which is described rather completely in my book, gets you to a pretty good result - and I'm nowhere near done.

I apologize for the fact that the run terminated at just under 90 mph, but I didn't have time to get to a drag strip, and have some safety rules I won't break when operating elsewhere. So, no quarter mile result shown below. (Quarter mile speed now exceeds 100 mph)

This run was NOT done using any drag strip techniques, e.g. preloading the torque converter. This was simple take foot off the brake and press the gas pedal. I even stupidly forgot to disable the traction control (remembered when I was uploading to the computer at home).

Don't ask me to again reproduce a written description here of the mods I did. That's why I wrote the book - so I don't have to do that several times per week. The purpose of this posting is to simply
1. Give some encouragement to those who wonder if it can be done
2. Give the current "milestone" in terms of my personal results on my own SSR

Note especially the 0 to 60 time, the 1/8 mile time, and the 0 to 1000' time. Note the still crappy 60 foot and 30 mph times - really need a decent high stall torque converter.

Note that the SSR is now getting pretty close to the 1/4 mile speed for a stock 03 / 04 in only 1/8 mile.

She is now under 11 seconds to 90 mph.

Oh, and by the way, note the vehicle weight. I weigh 235 lb and I test with 14 gallons of fuel aboard, so this was no flyweight driver in a stripped vehicle.

My automatic now shifts at 6500 for all gears (don't do this with a stock 03 / 04 valvetrain. I have a Z06 valvetrain)

And yes, the ambient conditions were "normal", not weirdly favorable. In fact, at 61 degrees, 30.37 barometric pressure, and 17% humidity, the "correction factor" that would be used on a dyno when measuring horsepower is a fraction of a percent off a perfect 1.00 factor.

The G-Tech was the most accurate performance computer under $1000 in the Car & Driver test done in their May 2005 issue, and gave PESSIMISTIC results compared to the drag strip timing lights.

For those whose eyesight makes viewing the G-Tech graph and table difficult:


0-30 mph: 2.138 sec

60 foot: 2.244 sec

0 to 60 mph: 5.482 sec

0 to 80 mph: 8.664

0 to 90 mph: 10.9 (you jhave to extrapolate the graph by 1 mph to see 90)

1000 ft: 11.745 sec

1/8 mile: 9.067 sec at 81.85 mph

Details in my book, especially Chapter 19.

Jim G
 

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JimG - The results of the work you have had done are very impressive. Do you have the ability to test other year SSR's with the same g-tech programmed the same way and on the same stretch of road? It would be interesting to see side by side comparisons of say a stock 03-04, modified 03-04, supercharged 03-04, stock 05-06, modified 05-06 and last the supercharged 05-06. Maybe at the next big get together. Are you going to show up at the Tri-State SouthWest SSR run to Laughlin? I would be willing to use my SSR for the G-Tech results, I am real interested in solid numbers for it right now. I will have 1/4 mile times for it after the SSR run to Laughlin, there will be a private track day here in March.
 

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Discussion Starter #3
2005SSR6speed: While I am willing and eager to do the kind of testing you are talking about, there are a couple of restrictions:

1. I cannot condone or even imagine a get-together like this anywhere except on a drag strip rented for the day, or some other privatesetting (e.g. private runway). It's one thing for a lone driver to do a few runs in a deserted location where traffic is sparse; it's somehting altogether different when there are multiple vehicles congregating. You start to trigger phrases like "competitive event" on either an insurance claim or traffic citation.

2. I am willing to travel, and since I am currently unemployed, have the time to do so, but, since currently unemployed, no funds to do so!

I do have all the required elements for successful, precision testing:

- G-Tech RR hardware and software

- All the required SSR vehicle data and the G-Tech already set up - just need to adjust G-Tech parameters that vary by individual vehicle: vehicle weight, driver weight, amount of fuel on board, engine shift points, etc)

- Custom written software to correctly calculate the correction factor for ambient temperature, air pressure, and humidity, for proper comparability

- Custom wirtten software that can closely predict performance based on an inputted dyno curve and final drive gear ratio, and can also adjust for headwinds, tailwinds, etc if unavoidable

- Software that can faciltate turning the G-Tech's NET horsepower available for acceleration after road and air friction, to estimated (limitations as discussed in another htread) rwhp, for those with no easy access to dynomometer testing

- A 1.7 pound notebook computer that houses ALL the software required for this and much more analysis, and connects to the G-Tech via USB

Maybe an "SSR Performance Conference & Festival" at some location accessible to many Fanatics???

You could do supercharger installs, I could do performance testing, someone else gear ratio swaps, etc. . . . :)

Jim G
 

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Discussion Starter #5
fourhands: I am in Austin, Texas.

p.s. Thanks to Mike Moro (mike in AZ), I am also equipped to do direct temperature readings on any underhood or underchassis component that we can physically reach and attach a thermocouple to.

Mike set me up with a really neat multimeter that accepts signals from a set of leads with thermocouples that he made up custom for me, and reads out the temperature directly in degrees!

Possible uses:

- REAL temperature of automatic transmission fluid
- Actual engine intake air temperature
- Actual radiator surface temperature

Jim G
 

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Jim I like the caption fourhands / correction FOURPAWS = FOURHOUNDS
Hope you can join us for the TRI STATE RUN

Will see you at the AVI
 

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I'm down with this...

We even have an 1/8th mile strip here but I would like to see qtr mile times. i'll keep watching and if it is done somewhere close, put me down. I think I posted earilier, I saw a stock 05 run 9.14 and 9.16 a few weeks ago. He had t/c on.

Scott
 

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Discussion Starter #11
Drag strips can commonly be rented at times they are not open to the public, at apparently decent rates.

When I was in Atlanta, this is what Reese Cox did one day to test his stroker and 427 LS1 (yes LS1, not LS7) Corvettes. The track normally opened to the public at 4pm. On a day when he knew attendance there would be sparse because of a really big event at another strip two hundred miles away, he offered to rent the track for two hours BEFORE they opened to the public. This was attractive to the track owner, and Reese got a good rate.

A private runway would seem like another choice, but there you don't have timing equipment to compare the G-Tech readings to.

Note that insurance coverage would probably be deemed ineffective when participating in "a competitive event".

Jim G
 

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convert 1/8 to 1/4 ???

Scott, Is there a general rule of thumb that tells you what the probable 1/4 mile time would be if you know the 1/8 mile time? I understand how many variables there are and if a car is geared to max at 1/8, it is not as easy as multiplying that time by, oh maybe, 1.6 to get the probable 1/4 mile time, but those 9 second times mean little to me. Would they equate to proabable high 14's or low 15's, maybe? thnx!
 

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My guess

14's. I've never been one for formulas when it comes to racing. to many variables. But given that jim has so much info, he can probably get real close since we are talking about a stock vehicle. Once you start moding, each mod changes how the vehicle will perform. The right combo, such as Jims new valve train, coupled with the right exhaust yeilds great results. However, any one of these could be made better or worse with the smallest change. I have seen vehicles actually slow down when to tall a gear is installed. I don't think this is the case with the 4:56s and the weight of our trucks. I really want t odo this mod but don't want to listen to the 4:56s and nobody I have talked to hasn't noticed some difference in the drive line. No one agrees either on the best gear set. Sooo many mods, sooooo little time. :cool
 

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Discussion Starter #14
I had run very low 14s before, when I was still restricting the valvetrain to lower shift points during its break-in.

The run I posted above, with the unrestricted 6500 rm shift points, shows 1/8th mile, 0 to 1000', and 0 to 80 mph times that are almost 1/4 second quicker than those earlier runs.

The 0 to 60 time is better than an 05 stock automatic SSR now, even with the non-drag strip start.

Comparing my 1/8th mile and time-to-speed times to stock 05s, I am certainly in the high 13s now.

The computer model, which correctly predicted the performance for the restricted shift points, and also the 0 to 60 time for the unrestricted shift points, says about 13.9 at 102. Remember, I weigh 235 and test with 14 gallon of fuel aboard, and use no drag strip techniques, so don't use this as any benchmark. It's merely what I can do myself without worrying about abusing the powertrain. I'll probably never do it unless I can get to a track some day. When I plug in a 160 lb driver and just 2 gallons of fuel, the 0 to 60 and quarter mile times each drop another 0.15 second or so.

The reputable math guys wil tell you very storngly not to try to estimate 1/4 mile times based solely on 1/8 mile times. It has been proven inaccurate. This is especially so with vehicles that are heavy, have transmissions with big gaps between gears, and are geared for highway use rather than the strip, as you end up not being able to use the power and transmission effectively. For example, an automatic transmission SSR with stock 3.73 gearing goes through the lights at less than 4000 rpm in 3rd gear, meaning it effectively uses only 2 of its 4 transmission gears! (After shifting from 2nd to 3rd, it hits only 3500 rpm where it makes only about 180 rwhp!)

With my 4.56 gearing, I would go through the timing lights at over 5300 rpm, which sounds much better, but is STILL at least 600 rpm below where my power STARTS to peak (nice flat peak from 5900 to 6500). To go "racing" with this very heavy vehicle, I would need even stiffer gearing!

Jim G
 

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Discussion Starter #15
I forgot something else: anyone trying to do acceleration testing needs to run their SSR harder than usual for at least 50 miles before testing. This is because the PCM "learns" and adjusts spark and a/f table values based on actual driving. If you are like me, and normally drive pretty conservatively, you will find that the 1st few runs you do at WOT will be "slow" compared to later runs, if you can find a place to do repetitive runs safely. The difference is the PCM adjusting and optimizing these tabular values. The dyno guys will ell you the same thing.

THis is why your SSR feels better after a nice spirited run along a winding road. It really IS running better.

This is hard to do properly, as getting lots of back to back runs at a strip is hard at most drag strips, and doing it on public roads is a significant safety problem as well as baiting any passing patrol cars for a "reckless driving" ticket.

Jim G
 

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I need to look into some details but I'm associated with a group that runs an autocross about every 4 months. There may be a way to set up a dragstrip as part of the autocross course and maybe do runs on Satuday before the Sunday autocross. Event would be in Camarillo, CA.
 

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Jim G - I tend to run mine real hard all the time

hdflstf - I am about 2.5 hours away from you, maybe we can get Pamona. There will be a private track day at California Speedway in March. As it gets closer I will post so we can get some SSR's out there to play.
 

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JimGnitecki said:
I forgot something else: anyone trying to do acceleration testing needs to run their SSR harder than usual for at least 50 miles before testing. This is because the PCM "learns" and adjusts spark and a/f table values based on actual driving. If you are like me, and normally drive pretty conservatively, you will find that the 1st few runs you do at WOT will be "slow" compared to later runs, if you can find a place to do repetitive runs safely. The difference is the PCM adjusting and optimizing these tabular values. The dyno guys will ell you the same thing.

THis is why your SSR feels better after a nice spirited run along a winding road. It really IS running better.

This is hard to do properly, as getting lots of back to back runs at a strip is hard at most drag strips, and doing it on public roads is a significant safety problem as well as baiting any passing patrol cars for a "reckless driving" ticket.

Jim G

Now that is smoe interesting information. Whenever I've 0-60'd I have never run it up before hand.....now I'm going to have to try that just to see what happens.
 

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WowFctr: I hope you are not trying to "time" runs using a stopwatch or something similar. While the inexperienced try this and think they are actually measuring times accurately, the pros know that the human mind and human body reaction time is notoriously inaccurate.

You need to use a performance computer or a drag strip to get a meaningful measurement.

Performance computers are now incredibly inexpensive compared to just a couple of years ago. $300 buys you a really good one - a G-Tech RR (NOT G-Tech SS, which lacks some of the really nice RR features). See
http://www.gtechpro.com

Whenever G-Tech or any other good brand upgrades to a newer model, they put older ones "on sale" for sometimes incredibly low prices.

The Car and Driver article above is very good as an "introductory" education as to which brands are good and which are not. But, it takes a lot of skill and discipline to use even a good performance computer ACCURATELY. I cover this in great detail (Chapter 19 - 13 pages) in my book.

When you PROPERLY eliminate wind, even slight gradients, and ambient condition anomalies, and use a CONSISTENT technique, the repetitive runs graph out right on top of each other. If they dont, either your control of the variables or your technique is flawed.

Also resist the temptation to use the "published formulas" that claim to tell you how much rwhp and crank hp your vehicles is producing based on the ET or terminal velocity, unless corroborated by multiple methods (e.g. drag strip results, G-Tech, AND formulas). Example: One of the most quoted formulas says that based on my 1/8th mile results, my automatic transmission 04 SSR is producing 369 rwhp and 462 crank hp! My SSR feels good but not THAT good!

Jim G
 

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Timing

I've had a G-tech for a while now. I had a friend compare it's results with the drag strip and they were right on. I was never trying to calculate HP, because that number doesn't really mean that much to me. I just wanted to improve my 0-60 time.

After running MANY times, I realize that even on the same road, in the same direction and only minutes apart, my times would vary. Sometimes because of different rate of accelator depression, sometimes because of some power "management" by the computer and sometimes tire slippage. I noted best times and average times.

I was actually thinking of doing a test with my clogged catalytic converters and retesting after they are replaced....just to see it there was a big difference. I'm guessing there won't be.
 
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