I have been asked several times questions like the one above. This question was asked of me in another thread, but since it was off the topic of that thread, I decided to make it a new thread.

I will try and be as unbiased as possible. I am in a very unique position in that I have driven both quite a bit (Underground Racing TTG and a Heffner TTG). As far as I know, only 2 people have driven both. Both w/ the race gas tune. Both w/ 17lbs of boost. The only difference being the UR TTG is an 06 model and the Heffner TTG being an 04 model so the gearing is all that separated the cars themselves before the TT's. There are some other differences, but they are performance related, which I believe should go out the window when doing the TT upgrade (ie, exhaust, filters).

The very first thing you'll notice is the sound. Heffner guys won't like this, and I'm sorry, but the Heffner car sounds ......well let's just say, not as good.... and that's an understatement. At least the one that I drove. The Underground car sounds like a finely tuned Formula 1 car. Several people commented on the sound difference that heard both. It's the first thing you notice when you turn the key.

The Underground car spools instantly and the Heffner car seemed to take just a little longer. Both were 6 speeds. Gearing plays a role in that as well. Once both cars start spooling though, the UR car definitely pulls harder. The Heffner car is by no means slow, it is just not quite as quick. There are SEVERAL differences in the systems. Because of time, I will just touch on one right now.

The fuel system:

The Heffner car that I drove was maxed out at 17lbs of boost. The reason for this was the fuel system was simply at it's end. Some have stated that a Heffner car could probably simply turn the boost up and accomplish the same thing that the Underground car has. After wanting to see what gives the edge to the UR car, I found that Heffner uses, in addition to the factory injectors, 10 additional injectors. These are actually OEM SRT Viper injectors (somewhere in the mid-30lb. range I believe). He replaces the 2 factory fuel pumps w/ (2) 255 pumps. There is really nothing wrong w/ this setup, it's actually an extremely economical way of delivering extra fuel since the added injectors can simply be removed from OEM Vipers (or bought) and used in the Lamborghinis....BUT the Heffner car pretty much maxed out at 17lbs of boost because of fuel constraints. Underground Racing also uses 10 additional injectors, but these are flow matched, custom 65lb injectors specifically made for the stand alone fuel system. Instead of simply replacing the factory fuel pumps w/ (2) 255 pumps, Underground Racing uses (2) 255 pumps IN ADDITION TO the factory fuel pumps providing plenty of fuel for extreme amounts of HP. These ADDITIONAL PUMPS are mounted w/ billet hangers. This is standard on all their builds.

One thing that was irritating w/ the Heffner setup on this car was that every time it got down to about an 1/8th tank of gas, the car was acting like it was running out of gas. Come to find out it was. The pumps were simply not low enough in the tank to pump that last 1/8th of a tank. Fortunately I was close by to getting some more race gas though and did not get stranded, so no big deal really, just good to know.

The Heffner car did throw an engine light after putting it through it's paces pretty good, but that was solved with a scanner simply resetting it. Both cars idled perfectly, drove like stock, and delivered power extremely smooth making them extremely fun to drive on the street. But the Heffner car just wasn't quite as fast as the Underground Racing car. Once I got used to that extra power, it was hard to go back. As I mentioned, there were many differences I saw after investigating both packages, but we will talk about some others at another time.

If you're interested in a TT system for your Gallardo, I couldn't be happier with my Underground Racing system. For me, it is the ULTIMATE STREET CAR!

 

Thanks for your informed opinion. Have you or anyone else that you know of done any top speed runs with these cars. Or driven on banked ovals at 200 mph + speeds. Or on road courses flat out. Would be nice to know if G is safe at these speeds and how the chassis can handle the almost doubled power. Only a few cars, like the Ruf RT12, can actually be driven quite safely and confidently at 200 mph and above but with most cars these speeds are more or less academic.

 

The cars (with stock gears) are limited to 200-202 mph. Bernard Vrooms car ran in the mile and crossed the line bouncing off the rev limiter in 6th gear at 201mph if I am not mistaken.

 

Sounds like an awesome ride. Are you running a re-tuned stock ECU or piggyback?

 

I remember when I had my Gallardo you were supposed to ALWAYS fill up at or just below a half a tank ... If you let it get too low it caused problems ... So maybe the tank issue was from the factory setup?

 

I've had my car alert me that it needed fuel (at ~ 1/8 tank) a few times, and I almost always have had it below 1/2 a tank when I fill up, and NEVER an issue.

I think part of the issue with the Gallardo fuel system is the 'range meter'. It may say you have 100 miles left to go before empty, but if you've driven easy for 200 miles before, and bought the average MPG up; but then start romping on it, it may 'think' you have 100 miles to empty, but not if you're driving agressive - You'll be out of fuel in 50.

 

thanks for the write up.. I have actually wondered what the main differences are between the systems as I have considered going with a TT setup for my superleggera... this definitely helps with my decision!

 

Nice comparison and write up, I run my G to the 1/8 tank and warning light level and have never had a problem..and I dont believe the computer as turbo50mike has pointed out the range can be decieving....depending on driving your methods...

 

Thanks for the post Kyle !!!!

Kyle's post is spot on as to what both cars are capable of.

I should know ... I own the 04' he is describing .

We have pics and video coming soon that will further
help describe what he has mentioned technically in
this thread.


.

 

I heard great things about both tuners.. but at the end of the day i went with Heffner mainly becasue of his proven track record w/reliability. He currently has 20+ cars running around and one has over 50k miles....

 

The ultimate setup

 

Good Choice made Bill.

I made the choice back in August of Last Year as well.

And if you do not turn your car up on high boost reliability
will not be an issue as with any car out there.

I chose to take my car and turn it up and make some
1/4 mile passes. Things didn't end up so well as the clutch
died on the second pass. Now we have taken a look at
the fuel system and electronics and it would have been
a major catastrophe if I had decided to take the car any
higher than 17psi.

 

Bill , when did you take your car to Heffner's ?

Was the Underground system out at the time ?

I am pretty sure it was in the development stage and
was not released at the time you decided to take
and mod your car.

That would make it a pretty easy decision don't you think?


.

 

 

Regardless of who's setup is better, heffner should get a lot of props for starting a trend that has brought out the best in many tuners who were already at a high level, like UR. Things can only get better, cheers to Heffner and UR!