Honestly you are not going to get the answer you are looking for with the question you are asking tied to ET. MPH will be a better indicator but the other questions are still important because cars that tend to hook really well tend to be down slightly on MPH due to less wheel speed at the first 300 feet of the track. A car that spins hard builds wheel speed faster which means it will gain speed/MPH at a faster pace.

John Meaney made some 11 second runs a while back in his C4 and if that is the only fact you know you would guess the car makes 450 to 500 flywheel horsepower at the crank. However, the car runs easy 154 to 157 mph trap speeds. The car makes well over 1000 horsepower on a mild tune on pump gas. My point is that ET and power are not nearly as related as Horsepower and MPH.

 

Alvin....Easy there fella. No need to blow a gasket over a simple topic.

And to not avoid any of your questions and answer them as good as I can - On the torque wrench idea: No I don't think I need to throw it out, nor did ANYONE suggest a dyno is thrown out. HOWEVER, do you think its a good idea since nascar has a torque wrench that its safe to assume EVERY torque wrench in existance is perfectly taken care of like they do theirs, a competient operator is using it that understand if you don't use it correctly you can get FALSE/MISLEADING readings.

And its NOT that I think its going out of calibration, what screws things up is its the ignorance of the operator believing that NOTHING can effects its outcome that screws people up. Next time you have a vette on your borrowed dyno, strap it down at different rear bumper heights enough to effect the 1/2 shaft angle. OH YEAH I AM SURE EVERY DYNO OPERATOR have been trained to check that out on these cars.

Do you think it will have an effect? Little hint: I knocked nearly .05sec off my 60' time perfecting where these things are on the launch.

On the weather stations you REALLY need to get in the loop with them. We have three of them in our crew when we hit the track..ALL SAME TAG system, and ALL 3 read differently. Up to 600ft. Might want to try another analogy. They like dynos you have to read with the "number" you get as irrelavent and differences more the key thing.

Lastly I really do not see anyone getting bent out of shape over the topic except a few of you guys. And believe me I am NOT argueing - just responding to other posts just like you and the others. The topic as you put it early on in post #10 is one of non-sensical meaning. So I must ask: Why are you participating?

And one last question pertaining to your #10 post...if the end all numbers are meaningless why the fuss as to what Beach and I have been simply stating about people getting bent out of shape on dyno numbers?

To me it seems like the right thing to do is to warn them that peak values are NOT meaningful at all to how a car is going to run. But that is just me.

Now if nathan and yourself can refrain from addressing me or quoting me we can probably carry on effectively with the discussion. I am however curious as to a few of the questions I asked of you. ahh nevermind - we already all know the answers to them.

Mike for what its worth - I believe your question and reasoning for the question are VERY valid.

 

That is exactly right, and to further illustrate or add onto Sams thoughts is as you go quicker and quicker (ET wise) the power needed to see gains is expodential.

for example: to go from 13.5 to 13.0sec ET may require ~30hp

To go from 10.5 to 10.0 you would need maybe 70 additional HP.

To go from 10.0 to 9.2 would take over 100hp.

And these are rwhp numbers!

Just further illustrates the caution needed when comparing power output to HP.

 

yawn... really..

 

Jesse,
You and I typically agree on a lot of stuff but in this case I feel Mike is missing a VERY key ingredient because his request does not take into account 60 foot times. Sixty foot times can vary as much as 7/10ths of a second in our C4's and we know that if the 60 foot time is off that much it could change the total ET by nearly a second. The big picture is not ET it is MPH and I am sure you recognize this which is why you have made the comments regarding the chassis dyno and the variables and accuracy of some of them.

 

Sam, I 150% agree with you. ET in itself should be thrown out the window. As should the HP figures really. They simply confuse the matter.

I believe Mike is trying to find a good setup for the street/strip. In that case, he should pay attention to ONLY MPH to meet his desired goals.

My thoughts behind his are simple. Give me a setup that can MPH and with some refinement you can get it to ET.

That is why I simply always state to individuals in search of a good setup to find one that meets your goals and copy it to a T.

I think he will become VERY confused if he tries to tie ET to HP to MPH with all these combos being listed. It would be enough to make anyone go loonies.

That is why I suggested the use of a MPH to ET calculator, which will give him a clearer picture of how much ET you can expect to achieve at a given weight.

It really is a confusing subject until you get it through your head MPH is for all intense purposes tied directly to HP and weight. People have a hard time seeing how a car can spin 100 ft out and still turn the same MPH +/- a few.

 

Thanks Jesse,

I thought we were thinking similar but I wanted to make sure. Have a great night.

Sam

 

Well, since I can't hook up obviously with my 2.1 60' time, my best 1/8th mile ETs are in the 8.80s @ 84 mph. That is like a 13.50 @ 105 mph in the 1/4th mile.

 

276hp, 13.12 @ 105.6 mph old car

I think around 700' too.

 

232 rwhp 324 rwtq
14.4@94.7

2700 ft elevation

TPI, auto, 3.07 gear

 

Rich, hope you dont mind me using your car to compare to mine.

Mine made 362rwhp weighs 3400 lbs, and with a 110 lb driver ran a best et of 11.71 at 117.3 mph. Now this was with a 3000 stall converter that is advertised to have 4% slippage. Comparing your car with my car shows that converter slippage is probably about right. Point being anyone with a 12-15% slippage (power loss) in their converter should get a better converter or find out what the actual slippage is.

As far as comparing hp to track times, my ideal track times are in my signature. However these can go back up by 3-4 tenths and mph go down by 3 or so on a hot humid day.

The one hp to track comparsion I can make is this. The season before last, I had a crappy tune which only made 342 hp. I had a Ed Wright generic chip for a STOCK 93 vette. It made 356 hp on the same dyno and same day. Now as you can see, the one chip made 16 more hp then the crappy chip.
Moving on to the track the crappy 342hp chip ran (1/8 mile track) 1-2 tenths et, and 1-2 mph slower then the 356 hp chip. Now these runs were done several times and comparsions were always made on the same track, same day, and back to back. So, to me, this proved that hp and mph do show a comparsion IF done on the same car, same setup, same day etc.

The reason I collected this data and made the comparsions was, the tuner of the crappy chip kept telling me that dyno numbers ment nothing. Take it to the track and get time slips. I did, and then his answer was I must be spinning with his chip. (I was running 26x11.50x17 et streets and believe me they do not spin on my car.) I even pointed out to him that a very reputable forum member, Hookedup (Dave) was behind my wife at cecil co. , watched her go around the water box (no burn out) and still run a 11.98 So this would show to any reasonable person that wheel spin is not my problem.
Course, you are always going to have those who could just as easly be arguing the second gunman in the bushes theory and no matter what data you show them, they will never admit they are wrong or could have made a mistake.
After 3 times of sending the chip back in, collecting all this data and working with him for 1 year, I gave up on his abilitys to tune my car and moved on to www.pcmforless.com Alvin's got it running to the specs in my signature, no more rich idle, and it passes emissions inspections!!

 

Adding more fuel to this....

60 foot time is critical to ET, and the general rule regarding the affect is: For every tenth or hundredth gained or lost at the 60 foot clocks, multiply it by about 1.5 to 2 (depending on the vehicle) for the corresponding gain or loss at the big end. Of course, as the ET's go faster (generally once you hit the 8's), the affect is less dramatic.

An example being: You lose .01 at the 60 foot, and top end, it's .02. All things being equal (which we with track experience know is hard to accomplish in the first place). The typical "forum car" is a street driven vehicle, and streeters are not a model of consistency, typically (unless it's a 17 second snoozer that wouldn't turn the tires over on ice). A manual transmission compounds the traction/consistency issue.

I think getting back to the OP's question, it should be addressed more like "what combo works for you as a general rule", rather than HP/dyno numbers as related to ET (hint... you can buy a real "high tech" device that corresponds HP/weight to ET...it's called a "Power Speed Calculator" made by Moroso..a plastic slide rule: just as accurate today as it was 20 years ago).

carry on...

 

No sense in beating around the bush about your comment about 12% slippage...so I will address you directly.

Again you demonstrate the capacity to show you don't have a CLUE about what your talking about. Trying to compare your 3000rpm stall LOCKUP converter to a 5000rpm stall FULL 8" RACE converter that is NON-LOCKUP is completely rediculous.

Furthermore your lockup converter does NOT have slip on the topend, so as the soup **** says, "NO LOSS FOR YOU!" And if your not locking up your converter on the topend, well again you demostrate you have no idea how to get a better time/MPH from your ride. Be sure to come back and say thanks for when you get a better MPH and ET from locking it.

ps: there is a whole lot better way to get your slip, rather than guessing at it. But I am sure already knew all the above already

As mentioned before to the others. Don't take pot-shots at me and there will be no need to correct what you clearly do not understand. It's a pretty simple concept.

Good luck at the track.

 

Racex,

Yepper your correcto. My correlation to the 60' times is close to 2.5 times different. This makes it more difficult to dial in the car and run a good number, especially on a questionable track surface. That is why I am seriously considering a "second" tune that detunes the car and kills a bunch of the bottom end. My end ET will be slower, but the launches will be more consistant, and make running the number much easier.

Typically on a given race day my 60' times are pretty consistant, varies from my last couple times at the strip ~0.03sec. Runs from 1.37-1.40 which isn't all that bad, but that is a difference of .075 which can be a pretty large swing in your dial.

Conversely to this topic is the top end. It is VERY hard to "scrub" ET from your time slip if you hit the brakes before the finish line. Your MPH will drop off a LOT, but the ET will still be within a .1sec or so. How about it RALPH! Add the airdamn to the equation to make it even more difficult. (he and I had a discussion the other day on the phone for lengths discussing the airdamn/front of the car tripping the beams at the finish prematurely.

LOTS of good things being discussed here that people may or may not be aware of going on. That is why it makes dialing in a number and running it very difficult or correlating to ET. You have to take MANY factors into consideration.

 

89 Z51 6 speed (TPI, bolt-on mods, ported '113's, stock cam and lower end)
3.33 gears, street tires (Yoko AVS Sport)
268 rwhp, 345 rwtq
3580 lbs. w/ driver

best run of 13.14@102, 1.91 60'
usually runs 13.3-13.5@105, 2.0x 60'
900 ft elevation, ~2000 DA

383 in the works ..........

 

Jesse, geez, sorry I upset you. Take a look at this link and maybe you may even learn something http://www.converter.cc/techtalk/tech3.htm

As far as how well my car is running, well its running about 4mph and 1/4 of a second faster then when you tuned it. :o
Look on the forum and see how many true street 350 vettes (that can pass emissions) are faster. Not many.
So to sum it up, I dont believe I will be thanking you for anything unless it will be my refund you spoke of 1 year ago.

 

Very Well Said.

 

Don't you just love the well if you don't see things my way you clearly don't understand whats happening?


Jesse is obviously right.. he knows all in his world.

You should quite wasting your time here jesse and call up dynojet to make sure they setup a program to train dyno shops how to use dynos.. Oh wait.. they already do.. its part of the deal when you buy a dyno from them!

and while your at it.. maybe you should call GM and tell them how they are wasting thier time with 39.7#/hr injectors in the new vette... They obviously don't know what they are doing....

 

Heaven forbid someone bring a bit of rationallity to the table.

A dyno REAL purpose is a tuning tool. Its like ignition scope.. If you go around comparing raw dyno numbers with raw dyno numbers than your in for a suprize. Everyone knows the type of transmission, rear-end, and stall will affect what is reported at the wheels.. Everyone should also know that there is a definate difference between dynojet, Mustang, superflow, and dynapack....


Track times also need to be taken with the same grain of salt.. If my car is not setup for the track your not going to show the power that your actually making.. Whats the problem in understanding that? If you don't than simply go out to test and tune and watch a new Z06 run a 12.5 at 110... we know that wasn't a indication of what the car was making... right??? Hell my car is by no means setup for the track and I know I have around .3-.4 tenths and a few mph left in it without touching the engine... that doesn't mean that the car is making less horsepower than what we measured on a dynojet dyno..



Bottom line.. Take your results with a grain of salt.. Realize how your setup effects your numbers weather they be MPH, ET, or RWHP.

Damn is everyone satisfied yet?

 

Dude you really can't be that THICK.

READ what you linked to:

As you can see, the converter with the lower stall torque ratio will multiply torque for a longer period of time than the converter with a higher stall torque ratio. As most of you know, most racing occurs above 3,000 RPMs. That's why the lower stall torque ratio often wins the race:

*Lower stall torque ratio is gentler on the tires at the initial launch, but it will pull harder for the remaining 1,305 ft. of the 1/4 mile. Less races will be lost at the starting line from excessive wheelspin.
Lower stall torque ratio will be more efficient and transmit more torque and horsepower to the tires. This translates into lower ETs and higher trap speeds!

Wait let me show you again, perhaps this time it will SINK into your two thick heads: Lower stall torque ratio will be more efficient and transmit more torque and horsepower to the tires.

Now the last sentence: This translates into lower ETs and higher trap speeds!

IS that not EXACTLY what I have been saying. HIGHER stall speeds have MORE slip! So comparing my converter at 5000rpm non-lockup to your 3000 stall speed converter is COMPLETELY rediculous.

Furthermore they are referring to the 97% efficiency at non-lockup state, when its locked the efficiecy is near at 100% - hence the reason you will gain even more ET/MPH.

As for your tune: Good, great, and happy Alvin and you feel its an accomplishment to eek a few lousy HP out of a tune in person than over mail order. TERRIFIC!

Its pretty obvious you guy's have a hard-on for me. Now go out and spend your time, especially you ALVIN with a SC'd FIREBIRD, that is barely breaking 95MPH in the 1/8th, with 50/50 alcohol injection. IF you want to be the all-star DYNO cheerleader - then go right ahead. I see its doing wonders for YOUR performance.

YEPPER, your really convincing me that you know what your doing.

And you can compare ANYTHING you want to GM this or that. I use what GIVES results - if you want to dispell those results my friends, you need to do better. And thus far you have not even beaten 85vet's 383 N/A he runs, mind you with the same 24# injectors you say you can't tune a 350 with

Now thus far you two have added NOTHING in the way of the topic at hand. You interject BS to disrupt the posting of information to fuel your little fixation that you have with me. Thanks, but I can really do without it. As can the rest of the people that have IMed me in the past day or so stating how assinine you guys are.

Here is the one I just got:

I have noticed a lot of people on here who think they know a bunch but end up having cars that run 12's or 13's and end up being pinhead know it alls about nothing. Sorry you have to put up with dillweeds.

Those are not my words, but someone else's. Just thought you would find it interesting to see what people think of you guys.

Now hopefully you two can grow up and either leave the topic or keep your posting relavant to the topic and not directed at people!

As I said before its a pretty simple concept.