JMS Power upgrades


CJ428

Farm GT
Mark II Lifetime
Le Mans 2010 Supporter
May 21, 2008
1,473
NJ
 
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FikseGTS

GT Owner
Apr 15, 2007
461
South Florida
nice gains across the board, would like to see some before/after performance metrics...

538 whp on a dyno jet is pretty weak though, my stock 2005 GT put down 525 whp on a dynojet...
 

STORMCAT

GT
Mark IV Lifetime
Le Mans 2010 Supporter
May 25, 2006
7,549
Ft. Lauderdale
ahh .. Their final numbers are what I would expect out of a car that's been broken in and the motor freed up a little.. I would like to see what the max boost pressure they produced.. Transaxles are pretty efficient . not sure I would buy the base HP run of 537. more than a 15% drive line loss from a transaxel is not common.. . The only way to make more power is to raise the boos level. From what I've seen the max out between 23 to 25 PSI with the current factory tune,,
 

B.M.F.

GT Owner
Mark II Lifetime
Jan 29, 2009
1,782
Minnesota
ahh .. Their final numbers are what I would expect out of a car that's been broken in and the motor freed up a little.. I would like to see what the max boost pressure they produced.. Transaxles are pretty efficient . not sure I would buy the base HP run of 537. more than a 15% drive line loss from a transaxel is not common.. . The only way to make more power is to raise the boos level. From what I've seen the max out between 23 to 25 PSI with the current factory tune,,

Most if not all the numbers i've seen are 540-550whp stock. I highly doubt many will surpass the 570whp mark stock with out a tune. The trap mph of dbk's car showed that these cars are not hp monsters nor were they meant to be. They are just a badass car! I believe there will be some tunes available with out doing all this wiring stuff in the near future here as i know of one of my buddies who's working on them now.
 

dbk

The Favor Factory™
Staff member
Le Mans 2010 Supporter
Jul 30, 2005
15,187
Metro Detroit
Please define "most," as in how many cars and where did you see them. I guarantee there haven't been 10 GTs on a dyno outside the factory, and realistically likely not even 5. My car made 576 rwhp, and a black car here did 590 rwhp on a dynojet. Most of the cars at the factory with 2-5 miles do ~570 rwhp on the factory dynojet, in a range of ~550-~590 rwhp. As Brian said, I would expect the "after" numbers here to be pretty close to a generic run-in car.

If you mess with the power output of this engine, just be aware:

You will immediately void your warranty
You will significantly shorten the lifespan of your powertrain
Getrag DCTs are not exceptionally robust at high levels of torque

For people that own a new GT, take my advice or leave it, but there is an extremely high probability some dude selling you a $1500 (or whatever) power upgrade will result in you footing the bill to split your $550k car in half to repair your damaged $40k powertrain.

This may not be a concern for some people. Good luck.
 

Specracer

GT Owner
Mark IV Lifetime
Nov 28, 2005
7,081
MA
I dont even have a pulley and tune on the 05. Not a snow balls chance... I would even ponder in my head, tuning the new one. Thats just me however.
 

Simon

GT Owner
Mark II Lifetime
Feb 19, 2013
1,230
Houston
DBK,

Is there a significant difference in RWHP in Stock v Ti v Heffner exhaust options?

Thanks
Simon
 

roketman

GT Owner
Mark IV Lifetime
Oct 24, 2005
7,994
ma.
I dont even have a pulley and tune on the 05. Not a snow balls chance... I would even ponder in my head, tuning the new one. Thats just me however.

I’m with Andy on this one
Most people will never use the car to itsfull capabilitys anyway
I believe you can’t outsmart the engineers who do this 40 hours a week
Just my 02
 

Specracer

GT Owner
Mark IV Lifetime
Nov 28, 2005
7,081
MA
I would bet the entire GT engineering team FANTASIZES about a 40 hour work week.

engineers who do this 40 hours a week
 

Cobrar

GT Owner
Mark II Lifetime
Jun 24, 2006
4,017
Metro Detroit
I would bet the entire GT engineering team FANTASIZES about a 40 hour work week.

That’s bankable. :biggrin
 
Mar 15, 2006
767
We modify 500 cars per year with most of them getting 100-500 HP over stock. We will be leaving our FGT Heritage stock for the reasons that DBK listed. Its all about risk vs reward and there are so many less expensive, less valuable cars that can be modified for bigger power gains.
 

FikseGTS

GT Owner
Apr 15, 2007
461
South Florida
tune didn't help much in 9000DA, at least it beat the Ferrari 488... :)

https://www.youtube.com/watch?v=8Mwk-26p8cM
 

PashaGT

GT Owner
Apr 23, 2016
178
Orange County
After reading many of the articles by forum member's I would agree it would be best to leave the NFGT alone and enjoy it fully the way it has been built. If John Hennessy with all of his experience is not modifying his car I would follow his logic. It's an extremely fast and capable vehicle the way it comes race ready from the factory!!
 

CJ428

Farm GT
Mark II Lifetime
Le Mans 2010 Supporter
May 21, 2008
1,473
NJ
alright :slap agreed.
 

davefordgt

GT Owner
Feb 10, 2006
302
Who car you going to use then for all the upgrade testing you have listed on your website. Wont some of those void the factory warranty?

http://hennesseyperformance.com/vehicles/ford/ford-gt/2017-ford-gt/

Stay tuned for more upgrade information for the 2018 Ford GT powered by the EcoBoost V6 Twin Turbo 3.5L motor. Planned upgrades include: high flow air induction systems, engine management tuning upgrades, high-flow intercooler systems, exhaust system upgrades, twin turbo system upgrades, engine upgrades and more.
 

timcantwell

Le Mans 2010 Sponsor * Moderator
Mark IV Lifetime
Le Mans 2010 Supporter
Jan 22, 2006
2,634
N.E. OH & Naples, FL
I dont even have a pulley and tune on the 05. Not a snow balls chance... I would even ponder in my head, tuning the new one. Thats just me however.

I do have a pulley and tune on two of my 05-06 GT’s but agree wholeheartedly that I shouldn’t mess with a good thing when dealing with my NGT.
 

FikseGTS

GT Owner
Apr 15, 2007
461
South Florida
I wonder which is faster, 2005 GT with pulley and tune vs stock NFGT..... :)


I do have a pulley and tune on two of my 05-06 GT’s but agree wholeheartedly that I shouldn’t mess with a good thing when dealing with my NGT.
 

cobra498

GT Owner
Jul 14, 2010
310
Central Ca;ifornia
I wonder which is faster, 2005 GT with pulley and tune vs stock NFGT..... :)

It would be difficult to beat a DC transmission because of constant engagement vs a standard manual clutch transmission even with slightly more power.
Computer controlled DC doesn't make mistakes, people do.
 

maxemus

GT Owner
Mark IV Lifetime
Apr 25, 2007
886
Miami, Florida
I wonder which is faster, 2005 GT with pulley and tune vs stock NFGT..... :)

Are you disappointed with your NFGT’s performance Brooks? Curious on your thoughts


Sent from my iPhone using Tapatalk
 

Jason Watt

Had both, sold both
Mark II Lifetime
Oct 14, 2005
1,227
Copenhagen, Denmark
No more advertising for NFGT power adding on the JMS site ;-)