Anyone try this? Is Hennessey reliable for these types of modificiations? What are the risks to the engine (if any)? Any experiences of qualified opinions are much appreciated!
Hennessey GT Upgrade to 700HP
- Thread starter MNGT
- Start date
Clax said:
:lol :lol
I'll just say if you ask a forum vendor like MD motorsports, Heffner Performance, etc, you can get the same exact numbers for a lesser price. I don't know, but I would assume a Hennessy modified car would depreciate faster because of negative connotation associated with his name. Could be wrong though, and his rep has recovered a bit from the hits it was taking a few years ago.
davefordgt
GT Owner
- Feb 10, 2006
- 302
abolfaz
GT Owner
BigsGT
Tungsten GT Owner
Hennessey Performance
GT Owner
- Mar 15, 2006
- 767
Hennessey sells a 2.68 in. pulley, mass air sensor mod, 2 K&N drop in the box filters and custom SCT programmer for $1,795. The net gain is around 90 rw hp with a stock exhaust and 100-110 rw hp with exhaust mods. You can also buy just a 2.68 in. blower pulley from him for $350.
abolfaz
GT Owner
Abolfaz- I quote Heffner from Viper Alley-
Heffner Performance said:This is a car we just finished up for one of our customers. The car sounds incredible. Mods are headers, exhaust, pulley (15 psi.), and some custom tuning. We dynoed each mod separately to see what each was worth. The headers and exhaust were only worth between 10 and 20 RWHP, the pulley and tuning account for the rest.
Dyno video:
http://www.viperalley.com/gallery/data/500/MOV00413.MPG
Oh what fun it is to drive.......
B O N Y
MODERATOR & FGT OWNER
MNGT said:
I have heard some awful $hit about Hennessey, do a google search on them and decide for yourself. Ask the Viper crew that posts here for their take. :eek
abolfaz said:
Yes!!!!!!!!!!!!!! That's the dyno sheet from my car. The car pulls like a train, and sounds even better. Mods - pulley, ECU, headers & muffler.
Jason supports and visits this site, so Jason if you read this, feel free to post the dyno link and any other information. I'm traveling for the next few days so I don't have access to it.
Jason has done work on other cars that I've owned, a Supercharged Viper to a 51 pick up. Always first class service, first class results, and a true gentleman to deal with. I give him the highest possible recommendation.
Tom
Jason did the pulley swap on my car and with tuning, picked up around 100rwhp to roughly 620 rwhp. No other changes and the car feels a ton faster.
Heffner is the man, as evidenced by my signature. :cheers
Heffner is the man, as evidenced by my signature. :cheers
SLF360
GT Owner
powa, baby !
my 50 cents, having driven one like this...
stefan
That's ('100) a good bit of power to have more.. makes the car another type of beast, but still amazingly controllable, due to its real good and handleable suspension and overall setup... Try something like it, and you won't turn back. The other thing that is really amazing, all of the car feels still fully in range of engineering, it wont even get hot (infact I see the opposite).. You never have the feel you are stressing anything in the car, only clutch like in first, if you are a jerk, be aware, you are loading it up, so better use it clean and technically correct, or take it easy at crossroads.. You smell it, you've skinned it.. piece by piece, prepare to replace, or learn to use it rightCHAD said:
my 50 cents, having driven one like this...
stefan
FlorIdaho Chris
Yeah, I've got one.
Fast Freddy
GPS'D 225 MPH
Any chance you have before and after exhaust mod dynographs? And if possible, could I get a copy of the actual dyno RUNFILEs? Do you recall how much timing was in the tune and the AFR? What was the pulley size? Thanks!!!Tom B said: