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Tim@NCTSLLC 08-27-2009 08:26 AM

The performance results thread
 
I am creating a thread where we (and others) can post up information related to performance results for our systems as the information becomes available.

The type of data applicable would be track times and dyno results (please post an image of the dyno sheet and/or time slip if possible), in vehicle monitoring such as dashhawk, G-Force, etc, runs (post a picture if at all possible).

In the post title block, please include vehicle information, for example;

"5.7 Cherokee Turbo 6 psi Track Time"

Thanks

Tim@NCTSLLC 08-27-2009 02:48 PM

Tabulated Results Page
 
This page reserved for tabulated results.

Tim@NCTSLLC 08-30-2009 10:53 PM

NCTS 5.7 Cherokee Turbo 6 psi 0-60 MPH Time
 
I was out playing with the Jeep and the Dashhawk tonight and.....

0 - 60 MPH in 4.76 seconds!

http://northcoastturbosystems.com/im...8/hpim0426.JPG

Not to bad for an all stock 5.7 with a bolt on turbo system.

We will see what the 1/4 mile times are when we go to Monster Mopar Weekend in St. Louis.

Frankie 08-30-2009 11:54 PM

Re: NCTS 5.7 Cherokee Turbo 6 psi 0-60 MPH Time
 
Quote:

Originally Posted by Tim@NCTSLLC (Post 54520)
I was out playing with the Jeep and the Dashhawk tonight and.....

0 - 60 MPH in 4.76 seconds!

Not to bad for an all stock 5.7 with a bolt on turbo system.

We will see what the 1/4 mile times are when we go to Monster Mopar Weekend in St. Louis.

WOW!!!!!!!!!!!!!!!!!!!!!!!!!!!! :thumbsup::thumbsup::thumbsup::thumbsup::thumbsup: :thumbsup:

Tim@NCTSLLC 08-31-2009 12:40 PM

5.7 Cherokee compared to the SRT-8 Cherokee (drive specs)
 
5.7 Cherokee compared to the SRT-8 Cherokee (drive specs)

Letís take a look at some of the specs between the two vehicles, and how they affect overall performance.

................................ SRT-8 .................................... 5.7 JGC

Curb Weight ............. 4819 ....................................... 4778

Axle drive ratio ......... 3.73 ....................................... 3.73

Weight Dist. F/R ....... 56/44 ...................................... 54/46

1st gear .................... 3.59 ....................................... 3.00

2nd gear ................... 2.19 ....................................... 1.67

3rd gear ................... 1.41 ....................................... 1.00

4th gear ................... 1.00 ....................................... 0.75

5th gear ................... 0.83 ....................................... 0.67

Final drive ratio ........ 3.1 ......................................... 2.50


So what do these numbers mean? The gear ratios in the SRT-8 were clearly selected for maximum performance whereas the transmission ratios in the 5.7 JGC were selected for economy. The SRT-8 ratios are evenly spaced, and it will shift much faster through the gears allowing the engine to rev faster. The SRT-8 starts out with a much lower ratio as well (3.59 versus 3.00), so the SRT-8 clearly has a better hole shot.

The 1st to 2nd shift is also a major difference. While the SRT-8 ratios are evenly spaced, the 5.7 JGC takes a big leap in 2nd gear ratio, 2.19 (SRT-8) versus 1.67 (JGC). This ratio and the 3rd gear ratio really slows down a stock 4.7 or 5.7, as it has to struggle more to pull through the gears and reach the next shift point with a much greater drop in rpm between shifts.

If there was a performance transmission option on the 5.7, it would make a big difference in overall performance.

So how do these numbers apply to the NCTS LLC Turbocharged 5.7 Cherokee? You have to keep in mind that due to the gear ratios, the turbocharged 5.7 will need to make more low end and midrange torque/HP to overcome the taller gear ratios to match up with the SRT-8 times.

4.76 seconds for a 0-60 time is very impressive as the JGC is pulling a taller gear ratio in 1st and 2nd than the SRT-8. So for this time to match a stock SRT-8 0-60 time, I must make more torque off the line to get the JGC moving and through the gears.

Experts I have talked with regarding the times, estimate that we are around 500 - 510 HP at the crank, and my times match up with the published times of a stock SRT-10 RAM that was at 505 HP at the crank, but with a much better gear spread in the transmission than the JGC.

Regarding a dyno, you would want to dyno the SRT-8 in 4th and the JGC in 3rd, as these are the 1/1 gears for the vehicles.

When considering modifications for your 5.7, you should lean towards those that are going to give you more low/mid range torque to help overcome your gear ratios in the transmission.

Escape 08-31-2009 05:15 PM

Re: The performance results thread
 
Excellent info Tim,

As soon as I find a AWD Mustang Dyno I'll post up the results.

Escape

Frankie 08-31-2009 06:18 PM

Re: The performance results thread
 
Tim, Can you please explain this futher? Thanks!

"Regarding a dyno, you would want to dyno the SRT-8 in 4th and the JGC in 3rd, as these are the 1/1 gears for the vehicles."

Tim@NCTSLLC 08-31-2009 09:04 PM

Re: The performance results thread
 
Quote:

Originally Posted by xoxSTUGOTSxox (Post 54844)
Tim, Can you please explain this futher? Thanks!

"Regarding a dyno, you would want to dyno the SRT-8 in 4th and the JGC in 3rd, as these are the 1/1 gears for the vehicles."

The majority of dyno pulls are done in whatever gear provides a 1/1 ratio. It helps so you are comparing apples to apples so to speak. If you dyno the JGC in 4th, you are going to be pulling through an overdrive gear which will skew the results.

---------- Post added at 10:04 PM ---------- Previous post was at 10:03 PM ----------

Quote:

Originally Posted by Escape (Post 54827)
Excellent info Tim,

As soon as I find a AWD Mustang Dyno I'll post up the results.

Escape

Just make sure those 31" BFG's are OFF! They are making your gear ratios even taller than stock.

Escape 08-31-2009 09:33 PM

Re: The performance results thread
 
Quote:

Originally Posted by Tim@NCTSLLC (Post 54950)
Just make sure those 31" BFG's are OFF! They are making your gear ratios even taller than stock.

No worries,

I have a line on some OEM SRT8 Rims. They are the lightest I can find so far, everything else I have found (that I like and doesn't cost an insane amount of cash) weighs a ton.

Escape

Frankie 08-31-2009 09:50 PM

Re: The performance results thread
 
Quote:

Originally Posted by Tim@NCTSLLC (Post 54950)
The majority of dyno pulls are done in whatever gear provides a 1/1 ratio. It helps so you are comparing apples to apples so to speak. If you dyno the JGC in 4th, you are going to be pulling through an overdrive gear which will skew the results.

Got ya! Thank you! :thumbsup:

Tim@NCTSLLC 10-13-2009 10:04 PM

NEW unofficial 1/4 mile time!
 
I went out tonight and run a 1/4 mile on the dashhawk just to see what it would do. The results?

12.77@107.5

This is a vast improvement over the results in St. Louis, pulling the ABS fuse is making a huge difference.

Now to get to the track and get an official time slip.

I did run an iEMS3 datalog, so I can go back and check the time stamp on it as well.

Looks like we are going to get that 12 second slip pretty quick!

HEMIBeast 10-14-2009 01:22 AM

Re: The performance results thread
 
Great information provided Tim!


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