Dyno Numbers.....I Think

[WhiteDevil]

Well i had a trip to the dyno today. It was really humid out and everything. It was a dyno day not private dyno session or anything. I showed up parked and popped the hood up. I told the guy i was there and he said oh your next. So i went with the car at full temp no cool down time at all. They strapped it down and brought it in gear and hammered it. The thing pulled like a frieght train until it hit 4,800ish rpm and hung there......spun em on the dyno. The guy gets out cranks the straps more and then does it again. Spun em again. So he cranks it again. Does a third back to back pull and it seemed to get better traction, but it still kinda took longer than i wuld have thought to get from 4,800-6,000rpm because it pulled so hard up to that point. I asked him if he thought it still spun them and he said i dont know it seemed to hook up better. The numbers are low ESPECIALLY in the torque area. But they just hurried me off to get the next person on the dyno. The numbers were 324rwhp and 322rwtq. I just cant be right. My old 302 combo made more Tq than that(326rwtq). I think it still spun on the dyno and he didnt want to admit it. Here is the dyno sheet. Im going to be dynoed this coming friday at a different place and see if the numbers are any different both will be dyno jets. Sorry for the rant. Dyno sheet below

View attachment 418323

 

[drakesdad]

I agree that something is up......your #'s should be higher with your set up.

 

[bimmertech]

something is up, the lines don't cross at 5250----hmmmm?

 

[final5-0]

Well John

Not sure what I'm looking at with the two curves on the fuel chart
but
looks like you could stand to be a bit fatter

I do know what you are talking about when doing one of those dyno pulls where a lot of peeps are involved

N O T H I N G

Like a private session

but

they sure are cheaper

Looking forward to the results from a more controlled session

Grady

 

[final5-0]

something is up, the lines don't cross at 5250----hmmmm?

Same rate of measurement was not used for hp & tq

Grady

 

[Therian]

which is pretty annoying

stats profs would fail any student that tried to hand in that dyno graph

 

[bimmertech]

Same rate of measurement was not used for hp & tq

Grady

and that right there folks is why this man makes the big bucks.

 

[WhiteDevil]

Yeah hopefully the private dyno runs at a different place will go better. I will tell them to make sure that they put the HP and TQ on the same curve.

 

[Pops Fun]

Yeah hopefully the private dyno runs at a different place will go better. I will tell them to make sure that they put the HP and TQ on the same curve.

Hi
The HP and Tq are always on different scales or am I missing something...

 

[Killercanary]

The HP and Dyno numbers are only on different scales if the dyno operator sets them that way. I think they do it to make the graphs look nicer. Normally you see it where the numbers vary a good bit between TQ and HP. I have no idea why they would do that on this graph since the numbers are so close.

Your AF ratio looks GREAT and FLAT, but I suggest trying to richen it up a little and see what happens to the HP and TQ numbers. The best way to tune on a dyno is to add timing first (adding timing tends to lean out the mxture a bit) assuming the AF is somewhat decent and then concentrate on the fuel side of things. To me it definitely looks like something happened at ~5300 with the TQ. It may just look worse than it is due to the scaling, because had they kept the scaling the same as the HP, the drop wouldn't look as bad.


Has anyone ever been able to tune out that dip in the beginning of the graph? I see it on a lot of 94-95 cars. I guess that is the tip-in perhaps?

 

[Zero Signal]

Yeah that is NOT a natural N/A motor's torque curve. It sounds like he didn't know what he was doing and you weren't positioned properly on the machine. It also looks like there's too much smoothing going on, but thats just a matter of opinion.

 

[blksn955.o]

From what I have seen on the tweecer boards/tuning boards and a few other "tooon sites" that our cars (5.0's and in gen 94-95's) like to run a tad fat. Most target 12.8 or so for N/A and see good results there. Maybe it has to do with were the trq. gets placed for our heavy cars with a slightly fatter mix? I remember reading several posts about 94-95ers seeing improvement from going from 13.1-13.2 to 12.8 or so.

As far as the dip goes, I have always been told to go WOT at "as close to 3k as possible" once the gear is reached the pull would be made in. I wonder if its some kind of change from loop state and lags for a second while load gets sorted out in the eec and dyno (if its a loaded dyno like a mustang dyno)?

What are your timing and A/F comandings, I thought you had a tweecer?

 

[Killercanary]

From what I have seen on the tweecer boards/tuning boards and a few other "tooon sites" that our cars (5.0's and in gen 94-95's) like to run a tad fat. Most target 12.8 or so for N/A and see good results there. Maybe it has to do with were the trq. gets placed for our heavy cars with a slightly fatter mix? I remember reading several posts about 94-95ers seeing improvement from going from 13.1-13.2 to 12.8 or so.

Yes, you are absolutely right., When I said leaner above I actually meant richer as in trageting 12.8 or so AF ratio. I had just gotten out of bed when I posted that and was half awake... OOPS!

Mine made its best power at AF's below 13:1.

 

[final5-0]

I think like Paul about them using different scales to make the curves look better.

I played around with them some in Excell and it CAN make a tq curve look more flat. However ... it is as they say ...... just smoke and mirrors if you look closely at the values.

As for the dip in the tq curve

You see it on some pulls and not on others
I've often thought it was from tire slip

I can see how it could be caused by the transition of going from CL to OL.
My combo used to produce a very lean spike there

I know I wanna have my pulls start from as low of an rpm as possible

Grady

 

[final5-0]

Yes, you are absolutely right., When I said leaner above I actually meant richer as in trageting 12.8 or so AF ratio. I had just gotten out of bed when I posted that and was half awake... OOPS!

Mine made its best power at AF's below 13:1.

My Q pertains to dyno pulls
but
First a Q for Paul

I've seen you say many times you were quickest with a really good cool down between passes.

I need to know the amount of time you would guess transpired between the time you started your Stang and you dropped the hammer for the pass?

Also Paul, do you know the ect when you started the Stang and started the pass?

The reason I ask is there is a certain amount of time that has to be dealt with where the ratio is gonna be fatter than it would be at normal temps.

I've seen it hose a dyno pull but I kinda think by the time you clean the tires and all ... it will not be an issue for the 1/4 mile ... but hey ... thought I would look into it with this opportunity

Grady

 

[Killercanary]

Grady, you want me to give all my secrets away???






















The car would pick up ~2 tenths and 1-2mph comparing a run made by driving an hour to the track and right to the starting line versus getting there an hour early and letting it cool. When I only had the factory gauge I didn't want to run until it was at or below the N on normal. With my autometer I like it to be at 150*. I keep my car OFF as much as possible in the lanes, if that means having to let the cars in front of me pull up a few spaces before I move then I do it, and I shut the car right back off until I have a few spaces to move again. I start my car as soon as I see the tech official controlling the lanes radioing in my number which is right before he sends me to the starting line. The car isn't on for more than a minute or 2 I guess from when I start it to when I run it. I then do whatever it takes to get the car cold before the next run as in running the heater on the return road, coasting as much as I can, etc. I pop my hood the second I get back into the lanes and shut it off as soon as I can. My painted intake heat sokes REALLY bad and even with a bag of ice it never gets cold to the touch.

 

[WhiteDevil]

Im running 33 degrees of timing on 91 octane. I just dont understand how my TQ numbers could possible be that low??? My 302 made more TQ than that.

 

[blksn955.o]

With alum. heads and 10:1 you "may" be able to get a few more * in there. Alum. heads will deal with heat better and the finsih on the chamber will also help fight det. I would try 35-36* and see how it feels esp. if you can get the A/F down to 12.8.

I run 31* with 10.33-10.6 comp. with an iron head and 12.8 commanded (need to verify before I go any higher on timing), I have not heard any ping...then agian I have 93 octane here.

 

[final5-0]

Grady, you want me to give all my secrets away???






















The car would pick up ~2 tenths and 1-2mph comparing a run made by driving an hour to the track and right to the starting line versus getting there an hour early and letting it cool. When I only had the factory gauge I didn't want to run until it was at or below the N on normal. With my autometer I like it to be at 150*. I keep my car OFF as much as possible in the lanes, if that means having to let the cars in front of me pull up a few spaces before I move then I do it, and I shut the car right back off until I have a few spaces to move again. I start my car as soon as I see the tech official controlling the lanes radioing in my number which is right before he sends me to the starting line. The car isn't on for more than a minute or 2 I guess from when I start it to when I run it. I then do whatever it takes to get the car cold before the next run as in running the heater on the return road, coasting as much as I can, etc. I pop my hood the second I get back into the lanes and shut it off as soon as I can. My painted intake heat sokes REALLY bad and even with a bag of ice it never gets cold to the touch.

Thanks Paul

I think I've seen you say you are runnin the t4m0 setup with your EEC Tuner.

I'm gonna poke around in that file and use your provided ect for a bit of research.

I gotta think by the time you clean the tires, the enrichment would not be in place.

When we were kids and at the strip every time it was open. We used to push our old cars to the line and would not fire em up until the starter yelled and shook his fist at us

Grady

 

[blksn955.o]

I have tried it both ways keeping the car off and pushing or only when the line moves a good bit to keep it running as little as possible. The problem I have had an issue is that at GIR (gateway were the WFC has been for awhile but not next year) on the test and tune nights you either get hot lapped or sit for 3hrs while bikes make 6 passes. The bracket nights are better as far as space/consistant amount of down time/number of runs. Its an extra 5$ but 100x's better IMHO, I just dont go out yet with any plans of making it past the qualify/elim. rounds.