DaveGS4

iTrader: (2)

I've been thinking about getting a Dyno done and decided to do some research. Surfed around, read some and located http://www.dynojet.com/lauto.shtml which lead me to a local speed shop (< 2 miles from my house) that has one that is open to the public.

Called and talked to them about setting up a session... For a "basic" dyno the charge is $100. If we go in a group, after the second car the price drops to $60. Dexter and I will both go, and my girlfriend is in with her NSX.

Anyone else in the Charlotte area that wants to get in, let me know.

Questions:

1) Is there anything I should be asking about a 'basic' dyno test? What are other options you guys who have had your cars dynoed have done? I read something about a high speed test as well.

2) Any issues or things to look out for / ask about?

3) Is this price in line?

Thanks,
David

1niceride

I have the same questions as you . The place down here is charging 75 dollars for half an hours time on the dyno and 125 for a whole hour .

Do you guys think that a half hour will be sufficient to get a good dyno reading ? or should i go for the whole hour ?

Any tips ?

Mean Gene

Guys - Those prices R a little higher than I have around my neck of the woods but aren't unreasonable. Thunder Racing charges $100 for an hour's worth of dyno time - typically ya can get 3-4 pulls in that time frame. The only problem with the GS is that it wants to downshift below 4k rpms so U'll need to get up to that engine speed before U hit WOT. Knock yourselves out!! BTW - it's a wonderful sound to hear the Borlas at WOT from the OUTSIDE!!

Kerr

the way it works here is a 85.00 for 3 pulls, 125 hour,

you need to decide what you are going to do and if there is anything you can tune. I mean if all you ahve is a intake exhaust, not a lot you can do, but if you have cam gears, which i dont think woek on a GS4, then all that does is leave you computer.

I know i made 3 pulls in my car, did about the same each time. Howerver i dont have anything to tune. Now on the other hand, Stephen (friend) went fron 435 to 606 in a hour and half, but that was adjusting wiht the boost, fuel compyter, timing, ect ect ect.

ALSO ASK IF THE TIME LIMIT START WHEN HE HAS EVERYTHING HOOKED UP OR IF IT STARTS WHEN YOU GET THERE.

gs400tx

Find someone from one of your local camaro/mustang web sites/clubs that have a group dyno day. The price comes way down and if your not tuning on it.. it just takes about 15 mins. No since paying for an hour...

You should check this tread
https://www.clublexus.com/forums/sho...threadid=23008

DaveGS4

iTrader: (2)

Thanks GS400tx - that's a great idea. I probably can stir up some interest in a couple of other forums and get a good sized group for it.



Gene (et al):

Your response made me start thinking... Since I've never done this (dyno) and have never even WATCHED a dyno session, I don't know how the throttle and gearing of the car is controlled during the test.

How is the accelleration and shifting (if needed) controlled during the run? Actually sitting in the car during the run? Do the dyno guys do this or me?

Your comment "BTW - it's a wonderful sound to hear the Borlas at WOT from the OUTSIDE!!" made me think that maybe I'm not actually in the car during the testing....

Sorry for the newbie questions on this - but it's a new thing for me.

Anything else I should be doing?
- Assume A/C and all accessories off.
- Does power mode and VSC make any difference at all (I don't think they would for final RWHP, but maybe the power mode would for the curve).
- Do you typically dyno with the hood open or closed (did anyone else read that ES thread on this topic?).

Thanks,
D

Mean Gene

Dave - It's the policy of my friend's racing shop where I do my dyno pulls to only allow a shop tech to run the car on the dyno. However, since Tommy & I R old drag racing friends, he lets me sit in the driver's seat & work the pedal if I want to. I just wanted to watch the computer screen on the last 2 pulls to get a visual on things. I ran my 2 of my pulls with the hood down to more closely simulate everyday driving & then did a third with it up - very little power difference. We did leave it up & had a large shop box fan blowing on the engine between runs. I had no accessories on & the VSC off ( shouldn't be much slippage on the rollers anyway ). Had the tranny mode neutral as the Power mode affects shifting points but we were already in top gear so there wouldn't be any more shifts. Kerr makes sense about only needing 1 or 2 pulls if U don't have any changes to make. I did an hour's time because I was in the process of testing the first generation RMM intake ( no heat shield ) versus the stock Lexus piece & I also swapped out the factory muffs for the Borlas.

QBranchCars

Dave,

I believe Gene answered most of your questions. I have witnessed dynoing of a couple of GS400's, including mine, on a Dynojet. Set up the car as Gene has stated, and we set E-shift in 3rd gear and let the engine run past 4K before WOT.

Heat affects the run, so your best run will probably be the first one of the day when the engine is cool. Subsequent runs require cooling off the engine in between. That's the reason you can get only 3-4 good runs in an hour.

A dyno is great, but consider finding out the stock HP before your mods to really determine your gains. Since you have the SRT HFI, you might run it as your first run of the day. Then swap the SRT intake out and put back the stock box and bypass the SRT ECU w/jumper (all should only take you 15 mins) and run it again. I would leave the Borlas on because it might be too impractical to remove.

$100/hr for dyno sounds about right.

Don't forget to post your numbers when you're done.


Gene,

I bet your run with the RMM intake yield less HP and TQ than the stock setup, am I correct? What was your stock power?

garnet92

Gene – That WOOSH you may have heard last Thursday and again Wednesday this week, was me flying by Alexandria on my way to Baton Rouge from Dallas and return (mom had an operation).

The GS was great on the road! I had L-Tuned exhaust and steering ecu put on the car before the trip but I’m not sure that the exhaust will stay on … considering switching back to Borla and selling the LT. I had Borla cat-backs on my old SC4 and always liked them. Have you heard both systems on a GS4? I don’t remember seeing a thread noting the difference (if any) you showed between stock and Borla on the dyno???

Mean Gene

Gar - First of all I hope your Mom's OK? I take it from your evaluation of the GS' road manners that yours was a road-based "WHOOSH?" Depending upon which way U went, U could have blown by me on I-10 heading to BR myself that Thursday ( 10-4 ) to check on my rental property I still have there. That was also the day that I posted taking the GS to the Price LeBlanc Lexus about the "Check Engine" light ( which may or may not be attributed to the Dragon T/C - will let ya'll know next week when I return to BR with the SRT bypass plug ). I'm afraid that U've caught me back at work & my dyno sheets are at the house but I recall calculating that the Borlas yielded almost 6 rwhp based on the numbers which came up on the dyno & using 80% for the drivetrain efficiency. Had the RMM muffs before the Borlas & they came up with a little more than 3 rwhp. Have heard it from several tuners that the factory exhaust system is reasonably efficient & the only HP to found there would be in changing out the stock muffs ( which R designed to be quiet & not free-flowing ). My dyno numbers seem to bear this out, at least on MY GS.
Calvin - The 1st gen RMM intake was a paradox of performance. My low range torque suffered ( below 4k I had to use the "glutemus maximus" dyno! ) & G-Tech Pro 0-60 times ( which INCREASED!!:eek: ). However, passing power FELT stronger & the dyno showed a small power increase kicking in around 4600 rpms & on up to 6100 - maybe 5-6 engine hp, if I recall correctly. Hardly what RMM claims in their ads but still an increase. I figure the larger intake piping allowed more air in but w/o an ECU to fatten up the spark/fuel curve, things basically leaned out & THAT'S what slowed by car down. I do remember the baseline pulls showing a totally stock power rating of 242.6 HP & 248.9 ft-lbs of torque. Using the 80% number, this equates into 303+ HP & 311+ torque at the engine - pretty close to the Lexus numbers of 300/310.