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I will try to post a video later. GM was pretty much right on the nose. Put down 241/241 at 5800 rpm on a mustang dyno. Thats a stock 97 Mark motor with functional IMRC's. It's a night and day difference compared to Lonnie tune! First pull wound up doing 128mph at 4000 in 3rd gear. Said he would have to do the rest in of the pulls in 2nd because he couldn't get it all the way through the rpm range in 3rd gear without doing like 150. Took it on the street to dial in the shifting. Normal driving it shifts just like it should. WOT though dead on the money! Holds the shifts out long but doesnt go over 6200. Said if it peaks at 5800 there's no reason to go to 7 grand and holding it like Lonnie had it set. All in all, very impressed on how much better the car performs! Just need to get some 3.73's in it now:)
 

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I'm glad you dyno'd it, but worst mistake ever is to set "shift points" without seeing the HP past the peak RPM <---THAT is what gets you in the ballpark as to where you should have it shift :facepalm: The wide-spread 1-2 gear ratio of the 4R70/75W necessitates winding out 1st gear to land in the meaty part of 2nd :)

Who did the tuning?
 

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Lee Blankenship at Blankinship tunning. He's in Shelbyville ky. Easy guy to deal with.
 

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Lee Blankenship at Blankinship tunning. He's in Shelbyville ky. Easy guy to deal with.
I'm sure he meant well, but for maximum acceleration you have have to see the HP as it curves down from the peak to properly set shift points. How far past the peak did he actually rev it? only to 6200? Who knows, it might be spot-on, or it might need some adjusting and it's best when you can see the full curve.
 

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Pretty good numbers you've got there!

What's the best way to tune shift points, GM? I seem to have it in my head that you log acceleration then have the shift complete when the acceleration rate is the same as/close to the acceleration before the shift and after the shift. I recall reading many posts by JL stressing that acceleration must be logged to set optimal shift points.
 

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Pretty good numbers you've got there!

What's the best way to tune shift points, GM? I seem to have it in my head that you log acceleration then have the shift complete when the acceleration rate is the same as/close to the acceleration before the shift and after the shift. I recall reading many posts by JL stressing that acceleration must be logged to set optimal shift points.
that is absolutely the best way because it takes converter slip out of the equation, but I don't know if Rollinthunder has an Xcal2 or 3 or what? ::confused: With only a chip, you obviously can't datalog and need to go by the HP curve and a bit of trial and error to see how far the RPMs drop on the upshifts.
 

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With mine, I found it best to tune the shift points at the track. You can concentrate on the 1-2 shift to find the best acceleration then work on the 2-3 shift for optimal acceleration.
you're doing the same thing, since without datalogging you pretty much have to go by trial and error. It just takes less trials when you can see the actual acceleration rate because you can zero-in on the proper shift point quicker.
 

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Seems off, borderline unlikely. What did they set your HP @ 50 # and weight on the mustang dyno? Or did they run it for a timed load, or did they just run it "unloaded". Those numbers seem high for stock cams in a 2nd gen intake mark dohc swap. Most important are these WCF #'s or regular numbers.
 

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Not sure what loaded and unloaded means or the WCF. Dyno and tunning are all foreign language to me. He did say that his simulates driving such as the faster you go on the dyno the more it puts a "load" like wind resistance im guessing. The only things done to the car that would affect dyno numbers im guessin are the 2.5 to 3 inch exhaust, fully ported and gasket matched the intake both upper and lower, CAI with the 02 GT MAF and I think thats about it. I will try to get the graph up later today. Oh and I have an xcal 2.
 

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That is precisely why I prefer to run vehicles "unloaded" on the mustang dyno, it simulates Dynajet numbers which are almost an industry standard.

Running it with an applied load is great for tuning however, without knowing what they set your vehicle weight and HP @ 50 (to simulate wind/speed resistance) in the mustang dyno setup page its hard to know how accurate your numbers are.

One thing I tend to notice on the mustang dyno though is you may be able to lie and tell it false weight and exaggerate HP numbers, but the TQ number never changes, hence the TQ never lies. I've seen turbo/nitrous cars put down 240hp/510tq loaded properly to simulate road use with the mustang software, and unloaded put down 380/510tq because the load retards timing and causes their numbers to read lower.

Since 9/10 people go off of dynajet numbers I run "unloaded" mustang dyno pulls for HP/TQ numbers, and load the dyno for tuning sessions or for people who want honest simulated load before and after modification numbers since realistically unless the next operator uses the same settings I use for weight and [email protected] the numbers could be skewed higher or lower.
 

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Ok so loaded dyno runs could be higher or lower depending on what they enter for weight and wind resistance. So the turbo/nitrous car ran lower hp because they over estimated the weight and wind resistance but in Rollinthunders bird they may have under estimated weight and wind resistance giving him higher hp numbers correct?

What were the torque numbers? Might be able to guess if it was over estimated or not since near stock 4vs typically dyno similair torque and hp numbers?.... Maybe
 

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Ok so loaded dyno runs could be higher or lower depending on what they enter for weight and wind resistance. So the turbo/nitrous car ran lower hp because they over estimated the weight and wind resistance but in Rollinthunders bird they may have under estimated weight and wind resistance giving him higher hp numbers correct?

Exactly

What were the torque numbers? Might be able to guess if it was over estimated or not since near stock 4vs typically dyno similair torque and hp numbers?.... Maybe
He listed his number as 241HP/241TQ, I believe that the TQ is spot on, HP may be a bit exaggerated. For example my daily driver 97 4.6 DOHC with port and polished heads, Cams, 3k TC, port/polished intake manifold, 3.27 gears, etc... (ALL MODS LISTED IN GALLERY) on 91 put down 227HP/241TQ set up with full load based on a PDF mustang issued this year for weight and [email protected], but I will be putting it back on the dyno at work to get unloaded numbers to simulate a dynajet comparison since most of the numbers people discuss or based on dynajet numbers.

I meant to strap my car down today but to be completely honest my car is a nightmare to strap since traditional straps will get melted by my exhaust I have to use chains for the rear. I may re-run my car tomorrow if I'm not overly busy. Today I was WAY to busy at work to get it done, fiddling around on my own car goes on the back burner for people who pay money lol.
 

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