twin turbo help
- Thread starter 930shark
- Start date
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HHGT
Guest
Apollo
GT Owner
I really would not say it looked stock - Maybe through the glass with the hood closed...:lol
There is a very thin line between the two set ups. I think it is almost a mute point on which is better unless you have a "very" specific requirement. I would venture to say that most would not be able to discern between the two in almost any situation or event. There are differences, and they have been discussed many times in threads. Both systems provide so much power it is almost not believable. I had the 4.0 Whipple and I really do not feel like I am missing much, if anything, with the TT only set up on the low end. I bet a TT/SC guy would say they do not feel they are missing anything on the top end. There is ample power in any range with either set up. For the most part, and in my opinion, the real difference is what you think "believe" is the better set up and the little nuances of how each works. They are both outstanding and proven reliable because the GT is so incredibly good to start with. Stay within the parameters of either system and you will not be disappointed! Either set up with the Ford GT will make your car way more than just about anything else in the world has to offer, and GT to GT would be a coin toss.:thumbsup
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tmcphail
GT Owner/Vendor
I have done all of the above and back with my car. I personally like it with the turbos alone but you can see it all here :
http://www.unleashedtuning.com/content/view/10/17/
In the end it depends on what your goals are.
http://www.unleashedtuning.com/content/view/10/17/
In the end it depends on what your goals are.
Indy GT
Yea, I got one...too
While I agree the GT engine as delivered to us by Ford is "incredible", the engine (as all engines have) has limits. I am not so sure I agree with your statement that both are reliable. IMO you need deep pockets to fund the GT engine with both turbocharging and supercharging. Air inlet temperatures due to the multiple compression systems and ineffective (in this application) intercooler will take its toll and cost you in the long run. This has been chronicled. Stick with one type of inlet compression system or the other.
skyrex
FORD GT OWNER
People are loyal to what they put on their car (brand wise) so it is hard to get someone to be "objective" about which set-up is better. I think they are both great systems from great companies.
That said I have a Heffner TT that has been nothing but a pleasure. 1019 rwhp on race gas, about 875 on my 91 tune I drive around town. I did 22 runs over 200mph at the last mile event I did and drove the car over 300 miles round trip to and from the event. I have put about 2,500 miles on my TT with no issues. My only complaint is I wish I would have done it sooner.
I think more people would go TT or TT/SC if the cost wasn't so high and there were more out there for people to experience. It is well worth the cost, but I have to admit I was a little nervous changing my car that dramatically without ever having driven or been in one. If you can even get a ride in one I would highly recommend it. I gave a ride once to a very experienced race/stunt driver and he said he never felt acceleration like that.....and I was only running my 91 tune. Another Forum owner in a stock GT was behind us and said he has never seen a car pull away from him so fast. :thumbsup :banana
One other important note. I drive my car....a little less than 12k so far, and the TT did not affect the drivability of local cruising. It is great in every type of driving. :cheers
That said I have a Heffner TT that has been nothing but a pleasure. 1019 rwhp on race gas, about 875 on my 91 tune I drive around town. I did 22 runs over 200mph at the last mile event I did and drove the car over 300 miles round trip to and from the event. I have put about 2,500 miles on my TT with no issues. My only complaint is I wish I would have done it sooner.
I think more people would go TT or TT/SC if the cost wasn't so high and there were more out there for people to experience. It is well worth the cost, but I have to admit I was a little nervous changing my car that dramatically without ever having driven or been in one. If you can even get a ride in one I would highly recommend it. I gave a ride once to a very experienced race/stunt driver and he said he never felt acceleration like that.....and I was only running my 91 tune. Another Forum owner in a stock GT was behind us and said he has never seen a car pull away from him so fast. :thumbsup :banana
One other important note. I drive my car....a little less than 12k so far, and the TT did not affect the drivability of local cruising. It is great in every type of driving. :cheers
BlackICE
GT Owner
Superfly
HERITAGE GT OWNER
Dom, promise me you'll take me for a ride when you put the twin snails on. I haven't been in a TT GT yet, and despite that, I'm still so very tempted to do it.....
Mullet
FORD GT OWNER
no problem! I was in the shop last night trying to figure out where to put the turbos and how to run the pipes. I really like the look when the factory air cleaner is still used but it makes it a bit more work to do. and longer tubing to make it work. i'm gonna sleep on the install for a few days then get started next week!
skyrex
FORD GT OWNER
Soooo what system did you decide on?? Best of luck with the personal install. I wish I had that kind of wrenching ability.....or for that matter desire to wrench. :lol :cheers no seriously, I own one hammer and two screw drivers and that is it......and a cordless drill I used twice :bored
.....and Pro I had figured I would get you back to Cali at some point and into my TT. :lol I guess I should have savored that trip you made to the GT school a little more. :willy :lol
.....and Pro I had figured I would get you back to Cali at some point and into my TT. :lol I guess I should have savored that trip you made to the GT school a little more. :willy :lol
Hennessey Performance
GT Owner
- Mar 15, 2006
- 767
This discussion has come up numerous times in the past. There are facts and there is some fiction based upon assumptions. We have built both twin turbo only and twin turbo / SC which has been a lot more popular. Heffner is capable of doing the same and I will guess that he has sold a lot more TT only than TT / SC. Here is the absolute bottom line, in my very humble opinion:
1. TT only will give you the greatest amount of power for a specific amount of boost. At 20 psi our TT / SC system on 93 octane makes about 840-860 rear wheel hp. At the same 20 psi boost we see around 870-900 rear wheel hp.
2. Going with a TT only set-up will give your 5.4 motor a huge amount of turbo lag. Below 3000 rpm you will feel like you are driving a honda. At 3500 rpm she starts to pull pretty good. At 4000 rpm the power comes on so strong you better be ready to shift to the next gear as you will hit redline very quickly. This is a great feeling and very exciting as long as you can live with not having any power below 3000 rpm. Again, this is my honest opinion, I am glad to sell TT only systems just as much as TT / SC systems.
3. The trade off is simple: You get a little bit more top end power with the TT only system. The TT / SC system has proven to deliver up to a 200 lb-ft rear wheels torque gain over the TT only set up from 1500 to 4500 rpm.
Both systems run on pump gas just fine. both systems will make more power on race gas. Both systems can support over 1000 rw hp on race gas and the factory fuel system with boost-a-pumps added. both systems are super fast and fun to drive. both systems have proven to be very reliable.
I suggest that any serious buyer contact the builders or owners of each system and arrange to go for a ride in each set-up. After you do you will know which one is the best. Opinions and commentary from the forum are great and informative. But there is nothing like experiencing each setup while riding in a 1000 hp FGT!
Good luck.
1. TT only will give you the greatest amount of power for a specific amount of boost. At 20 psi our TT / SC system on 93 octane makes about 840-860 rear wheel hp. At the same 20 psi boost we see around 870-900 rear wheel hp.
2. Going with a TT only set-up will give your 5.4 motor a huge amount of turbo lag. Below 3000 rpm you will feel like you are driving a honda. At 3500 rpm she starts to pull pretty good. At 4000 rpm the power comes on so strong you better be ready to shift to the next gear as you will hit redline very quickly. This is a great feeling and very exciting as long as you can live with not having any power below 3000 rpm. Again, this is my honest opinion, I am glad to sell TT only systems just as much as TT / SC systems.
3. The trade off is simple: You get a little bit more top end power with the TT only system. The TT / SC system has proven to deliver up to a 200 lb-ft rear wheels torque gain over the TT only set up from 1500 to 4500 rpm.
Both systems run on pump gas just fine. both systems will make more power on race gas. Both systems can support over 1000 rw hp on race gas and the factory fuel system with boost-a-pumps added. both systems are super fast and fun to drive. both systems have proven to be very reliable.
I suggest that any serious buyer contact the builders or owners of each system and arrange to go for a ride in each set-up. After you do you will know which one is the best. Opinions and commentary from the forum are great and informative. But there is nothing like experiencing each setup while riding in a 1000 hp FGT!
Good luck.
BlackICE
GT Owner
1. It is a fact that the TT+SC will have more thrust in the 1500-4000 RPM compared to TT ONLY
2. I respectfully disagree that a TT-only feels like a Honda below 3000 RPM. It does not. While statistically slower than a TT+SC in the low rpm's, the trade-off is that the TT "feels" much free-r and is more rev-happy. (Like the engine's task of turning the equilavant of 50 AC compressors is suddenly removed.) This new found rev happiness, SUBSTANTIALLY mitigates the performance disadvantage... and it is one of the hardest things to describe in words.
3. The boost difference on the top end to get equivalent perfomance from the TT+SC is substantial and is the HUGE weak point of the TT+SC. One reference (there are likely many others) is Apollo's TT-ONLY and Mullet's TT+SC Texas Mile runs. The cars ran a different times of day but Mullet' s TT+SC saw a 3-4 mph advantage over Apollo. But Mullet was running 29lbs of boost and Apollo was running 21lbs.
4. I respect your opinion - which in essence is that you shouldn't be asked to give up any low-end grunt.
5. My opinion is that the negative side of the TT+SC overshadows the small low-end benefit.
2. I respectfully disagree that a TT-only feels like a Honda below 3000 RPM. It does not. While statistically slower than a TT+SC in the low rpm's, the trade-off is that the TT "feels" much free-r and is more rev-happy. (Like the engine's task of turning the equilavant of 50 AC compressors is suddenly removed.) This new found rev happiness, SUBSTANTIALLY mitigates the performance disadvantage... and it is one of the hardest things to describe in words.
3. The boost difference on the top end to get equivalent perfomance from the TT+SC is substantial and is the HUGE weak point of the TT+SC. One reference (there are likely many others) is Apollo's TT-ONLY and Mullet's TT+SC Texas Mile runs. The cars ran a different times of day but Mullet' s TT+SC saw a 3-4 mph advantage over Apollo. But Mullet was running 29lbs of boost and Apollo was running 21lbs.
4. I respect your opinion - which in essence is that you shouldn't be asked to give up any low-end grunt.
5. My opinion is that the negative side of the TT+SC overshadows the small low-end benefit.
BlackICE
GT Owner
There are some pretty fast Honda nowadays, but I wouldn't say that the TT is slower than a Honda either, although it may feel like it from 0-30 MPH.
Apollo
GT Owner
One reference (there are likely many others) is Apollo's TT-ONLY and Mullet's TT+SC Texas Mile runs. The cars ran a different times of day but Mullet' s TT+SC saw a 3-4 mph advantage over Apollo. But Mullet was running 29lbs of boost and Apollo was running 21lbs
...and I was fighting a seriously slipping clutch... Still would have been tough to take down Mullet.:biggrin
...and I was fighting a seriously slipping clutch... Still would have been tough to take down Mullet.:biggrin