Hey guys...

My school had 'Open Dyno' day today.  I sat around all day because I was too much of a wuss to run my car.  My trans is still shifting like butt.  :(

But my instructorfinally talked me into getting on, so I did.  I did the 4 runs from a 5mph roll and went to the top of second gear.  Here are the stats...


I dont have the rpms that I hit the peaks because the tach lead was messed up, but it did record the mph.

Anyway... here are the numbers...  I'll have the dyno sheet scanned this weekend for the non-beleivers...

Run #1.  153 hp  346.3 lb/tq
Run #2.  170 hp  341.1 lb/tq
Run #3.  186.5hp  377 lb/tq
Run #4.  173.5hp  363.4 lb/tq

IS THIS SHIT NORMAL OR WHAT?!  This thing had a major torque spike, and then it looks like the wastegate opened and brought it back down, but the boost creeped back up towards the top of second gear.  At the top of second gear, the torque was at just above 350.

All of these runs are without mufflers.

Bad?  Good?  What have you guys gotten out of them?

later,
Zach

HOLY  TORQUE!  :shock:

I wanted to get my car dynoed with the chip, but my tranny bit the dust.  You must have a TopGun chip right??

Got torque?

That's whp right?

Hey guys...

This is with NO upgraded chip, nor a new crossover.  Actually... my crossover is leaking pretty badly.

:?:   My car a freak?

I've got permission to go back and run it again next year when I get enough money to get a chip and crossover.

OH yeah.  That is to the wheels.

Quote from: ZachSHey guys...

This is with NO upgraded chip, nor a new crossover.  Actually... my crossover is leaking pretty badly.

:?:   My car a freak?

I've got permission to go back and run it again next year when I get enough money to get a chip and crossover.

OH yeah.  That is to the wheels.

Nice info. I can't explain the torque issue, no wonder the trans took a crap. I don't have a lot of experience with dyno's and what the tranny can affect the readings. Remember the torque converter multiplies the available torque, so that may have something to do with it. I've never seen any discussion on this though. Does the dyno have some sort of calibration built in for wheel size gearing etc?

Hey guys...

Here is the scan from my dyno run.

My trans shift was REALLY weak going into first. :(
My boost spiked on the dyno (as you can see by the major spike), and it almost looks as if the wastegate is bad or defective.  Whats up with this?  The dyno instructor about shit himself when the tires spun off of the 5 mph roll.  The only other car in our lab that can do that is a 93 T/A with 397 lb/tq.

At any rate... I'm damn impressed.  I got 4 runs in, and my lowest dyno reading was

Quote from: Chris A

Quote from: ZachSHey guys...

This is with NO upgraded chip, nor a new crossover.  Actually... my crossover is leaking pretty badly.

:?:   My car a freak?

I've got permission to go back and run it again next year when I get enough money to get a chip and crossover.

OH yeah.  That is to the wheels.

Nice info. I can't explain the torque issue, no wonder the trans took a crap. I don't have a lot of experience with dyno's and what the tranny can affect the readings. Remember the torque converter multiplies the available torque, so that may have something to do with it. I've never seen any discussion on this though. Does the dyno have some sort of calibration built in for wheel size gearing etc?

Yes.  It takes the stock wheel size and everything.  The program that our school runs, has a TON of car settings saved in the computer.  And believe it or not a 90 Pontiac McLaren Grand Prix was one of the options.  So we chose it, verified the settings, and changed the dyno run to RO (roll on), strapped my baby down and did the runs.  There wasnt much time at all between the runs.

The dyno cell is automatically climate controlled to 86 Degrees F.

Look how high the torque goes in second gear... even after the initial spike.  It still goes near 350 it looks like near the top of second.  First gear is just too short... especially on the dyno.  I wish I had a stick... that way I could do a full pull in 3rd gear... without having to worry about the trans kicking back down.  

hehe... anybody want an auto trans from ac/delco with a 24K warranty?!  I'll trade ya for a 5-speed!  :D

ttt for my scan.   Any comments?  Anyone ever seen a freak like this?   :shock:

That looks really cool Zach! I think it is awesome that your school has a friggin' dyno..I am green with envy! Have any of the ricer boys put their cars on there? Have any comparisons to a VTEC Honda motor? For Waskie's sake of course... :lol:

At the expense of looking like the doubting Thomas here,  377 lb ft of torque is very hard to believe to by accurate especially since the car is
not highly modified.  The new Corvette probably wouldn't get those torque readings with a 5.7 liter V8. The only way these numbers could be correct is if you are unknowingly building a lot more booste than you believe you are but the HP #s should be higher too.  Is your car one of those that will really fry the tires from a start ?  That would be a good clue whether your getting more torque than average.

Well, have now joined 2 new TGP boards in one night, must be nuts but for sure been a while for me, don’t want anyone thinking I am back fully though, far from it but good things to reveal soon for all TGP owners, maybe a few other 60 degree V6 owners.

As for this dyno run, great looking numbers, have seen a few sent to me over the years, this one has its own character, but think I can explain a few things, hopefully not make it another mini-novel that I am known to have written in the past

First the power drop after shift is 2 things, first is common to the stock chip, if you watch the boost level and corresponding wastegate duty-cycle you will note the ECM IS indeed commanding the boost level to drop (yes a lot) after shift.  Second drop is from the tranny slipping as it progresses into the next gear, and any 4T60 that has a failing tranny from this condition is known as slid-bump problem, think of it like revving up a manual tranny and dumping the clutch, same situation going in as in the auto tran slipping before it bites into the next gear…….and now that a few brains have been given time to hashing that though around, yes a proper working auto tranny is easier on a drivetrain than a manual (fluid drive does absorb some power but much more abuse/shock than actual power, which is around 12 to 15% in tests), so maybe this will explain why there is little to worry about as far as breaking half-shafts in the auto tranny TGP, we will find out soon here as for manual tranny versions from the few that have done this setup and are running stock or my manual tranny TopGun chip.  So to recap, that huge peak torque number is the wham effect as your tranny slid/revved into the next gear, TGP engines make 275 lb ft with a chip’d setup using the fullest/safe potential of the stock internals/turbo setup, running around 10 to 12 psi on a real boost gauge, not reading off the gauge cluster boost indicator gauge!  I also noticed some changes in running the engine twice with air filter and twice without, not much difference without a chip tweaking into higher boost.

Anyways, glad to see you survived, might want to call up some techs to have that dyno checked out, there is still some oddities left to resolve, have the prof run some conversions of torque to horsepower, this will show up the real proof there are some calibration problems.  FACT: HorsePower = torque X RPM /5252, so if we plug in 377 lb ft of torque at say 4,000 rpm and divide by 5252 we get this figure, 377 X 4000 = 1508000 divide this by 5252 and we get 287 hp, not 170 as in the graph, but you still got a ways to go till the stock block will complain which is past 350 hp and 8,500 rpm, properly balanced for that much rpm though.

Jeff M

Good to see you here also Jeff. What good is coming to us? Please tell!

Ok, I can wait. :drinking:  :drinking:  :drinking:  :drinking:  :silly:

yeah, definately good to see you, BTY i like novels