Twin Turbo's in a GT40 ?

[Kevin]

I've heard of a twin turbo in a GT40. Question- there doesn't seem to be much room in the exhaust to house them, how is this accomplished ? Any photo's and information would be appreciated.

[Bill Hara]

anyone here ever slap on a turbo/ supercharger?

Check this thread out.


Bill.

[DBLDREW]

Here is a few videos of a twin turbo Ford GT…

http://videos.streetfire.net/search/...8d7d6b0801.htm


http://videos.streetfire.net/search/...928d979c59.htm


http://videos.streetfire.net/search/...64e80a1895.htm

[Kevin]

It look tight. The mustang headers up-side down is a good idea. Heat may be a big problem. Thanks for the links guys.

[Mark Worthington]

Originally Posted by DBLDREW

Here is a few videos of a twin turbo Ford GT…

http://videos.streetfire.net/search/...8d7d6b0801.htm


http://videos.streetfire.net/search/...928d979c59.htm


http://videos.streetfire.net/search/...64e80a1895.htm

Street racing a Ford GT against a punk in a Mustang makes Jesus cry. That second video make me want to puke, especially the bit about the GT suffering from turbo lag. The only reasons turbo lag would be an issue are if the packaging mandated placement of the turbos far from the exhaust ports or, more likely, if the "tuner" bolted on overly large turbos so that he would have dyno bragging rights. Furthermore, it appears that the "tuner" who did this work has an inertia dyno. I would hope the car was tuned on an eddy current sydno and the Dynojet was used for bragging rights, but I doubt it.

I was all hot about twin turbos in a GT40 when I first thought about buying a GT40 kit. However, I eventually came to the conclusion that the bundle-of-snakes crossover exhaust is one of the most endearing aspects of a GT40, both visually and audibly. Twin turbos would totally screw that up, IMO. Then there's the packaging, heat management, tuning and throttle modulation issues. I wouldn't hesitate to do twin turbos on a Cobra but I don't think a GT40 is an appropriate application for turbocharging.

[Doug Sainlar]

I posted a Q regarding supercharging a SBF in a GT40 kit, and here is what Bob Putnam of ERA had to say:

"It seems to me that if you want to be foolish, there's much more room for turbochargers."

My response was that I was not at all sure I wanted to be foolish. If you are interested in that discussion, here is the thread:

Any experience with supercharged SBF motors in a GT40?

Good luck!

[Craig White]

Originally Posted by Mark Worthington

but I don't think a GT40 is an appropriate application for turbocharging.

Hmm, I thought turbo charging was suitable for every situation.

[DBLDREW]

Originally Posted by Mark Worthington

The only reasons turbo lag would be an issue are if the packaging mandated placement of the turbos far from the exhaust ports or, more likely, if the "tuner" bolted on overly large turbos so that he would have dyno bragging rights. Furthermore, it appears that the "tuner" who did this work has an inertia dyno. I would hope the car was tuned on an eddy current sydno and the Dynojet was used for bragging rights, but I doubt it.

I don’t think it would be possible to mount the turbos too far away from the exhaust ports in a mid engine car. Hell I’ve seen videos of people mounting turbos at the tail end of a mustang with good results. Regardless any turbo is going to have some lag, and considering he was in 3rd gear and they were running at 50-55mph (or somewhere in that range) that would put him around 2600-2800 rpm. Running that low of a rpm is going to give you some turbo lag. That is just the nature of turbos your going to get some amount of lag there is now way around it. Now you could design the system to be able to spool up faster by going with smaller turbos but the trade off is less total power. So considering the car made over 1000hp with race gas it seems to me that they went with larger turbos that will take a little longer to spool up.

But we are really missing the big picture here, that transaxle is pretty impressive to be able to take that kind of abuse!! To bad they are over $14,000

[Kevin]

I agree with most said. The "bundle of snakes" is a cool system and would hate to screw them up. From what I've seen at my buddies automotive shop and has a mustang chassis dyno, he gets a lot of "tuners" installing turbo's. For the added heat & detonation, he installs before/after coolers, water or methanol injection, programmable computers ect.... I know turbos can add a lot of hp but, to what expense ? Talk about a bundle of snakes ! He has a customer with a 89' Chevy truck. With a new block, good rods, pistons, crank ect., and the above stated parts, he has apx. 20k into this engine & system..........in a old truck ! To each it's own I guess. Anyway, I have around 10k in my 427 cobra motor. 563 hp. He'll have apx. 600-700 hp. Is it really worth the expense ? Plus, mine sounds like a cobra should, radical cam, compression, and the GT40 is no different. I love the low down grunt of American muscle power and not the tuner whoosh. If it's a 12 cylinder Ferrari,....... that's different. I did not post to ask for turbo information for my (hopefully) future GT-40, rather out of curiosity. If I use any power adder for my cobra or a GT-40, it would be a centrifugal super charger or the small blower like the new GT. Again, I think the big issue here is heat and exhaust.

[DBLDREW]

I agree that the bundle of snakes is very impressive but for me what is even more impressive is the weber/stack injection setup. Trading the stack injection for a turbo setup would be a very hard pill to swallow.

[Kevin]

Couldn't agree more. That's one of the reasons that my GT build would be so expensive, the engine, webbers and snakes.

[JohnC]

IMO, turbos are tough to make visually appealing. I own both a twin turbo car and a single turbo car, and the turbos just look like they've been "hung" on there, even though one is an OEM setup.

Gale Banks probably does the best job of making a twin turbo V8 look visually appealing and "engineered" instead of just "hung on".

Below the Gale Banks TT photos is the nicest blower setup I've ever seen, on a one-off V10 Mustang project. IMO, that competes very well with a set of Webers or ITB's for visual appeal.

John

[Kevin]

That looks fantastic and everything is in it's place. Do you know what the cost is ? What is the cu. in and the hp numbers ? I'll look at his site.

[JohnC]

Have a look on his website - Banks has a long history with Chevy, but builds engines and "kits" for most domestic lumps these days. That particular motor was a 6.0l built with a Dart block and lots of other goodies, and produced somewhere around 1100 BHP @ 6800 with 20psi of boost.

You'd be hard pressed to find a transaxle that could handle the output of that thing, and as others have said, for a GT40, 350-450 BHP is apparently plenty of power anyway. After all, it's really a 2000 lb racecar that's also street legal, not a 3500 lb Mustang, trying to be a racecar.

John

[Kevin]

It's a incredible engine but, I'm sure at a incredible price too !
Some salvation with the gearbox is, just so you don't dump the clutch from a stop, all that hp & torque would not hit the trans axle but, were still talking say, 600-700. What is this "G" (something) trans axle ? Sounds like new cost is between 6k to 9k ? That's hard to believe. I e-mailed Banks and they don't do Fords, just Chevy.

[Doug Sainlar]

Originally Posted by 427HISS

What is this "G" (something) trans axle ? Sounds like new cost is between 6k to 9k ? That's hard to believe.

Might you be referring to the Porsche G50 transaxle? It's one of the mid-level power choices for our GT40 replicas. If you need more power handling capacity, the ZF transaxle is generally regarded as a bit stronger, and IMHO not that much more expensive (I've seen references to ZF transmissions being available starting at the upper price you noted for the G50). Now, if you really want a transaxle that might handle this type of horsepower, check out Ford's GT transaxle--Ford Motorsports sells them for around $14,500, but they are reported to be very strong.

As you can see, in this obsession we are usually limited by the transaxle rather than the engine.

Doug

[Kevin]

$14,500.........good GOD !
The GT dream is getting more out of hand everyday. I can see now, that the price range for the way I would want it, is clearly in the 70-80k price. Even the 10k is hard to swallow. I have a friend that is a fantastic mechanic with his own shop and he specializes in straight axle rear ends and transmissions. What are prices used, damaged or needed to be rebuilt ?

[Bill Musarra]

Looking for a trans to hold all that poswer??????

Belt drive paddel shift 1000 +HP

Bill

[Kevin]

That is quite the feet in engineering !
Can't wait for futher up dates.
Thank you Bill.

[Doug Sainlar]

Originally Posted by 427HISS

$14,500.........good GOD !
The GT dream is getting more out of hand everyday. I can see now, that the price range for the way I would want it, is clearly in the 70-80k price.

I think your estimate is probably right on. When you take into account the price of the kit itself, plus the cost of the drivetrain/paint job/tba and assorted parts that are not included in even the most complete kit, etc. I suspect $70K is a good starting point for a completed vehicle--and that is not counting anything for the labor you put into it to build it.

That makes a good used GT40, or perhaps an unfinished build, a pretty good value, doesn't it? I've seen some in the For Sale section that made me drool, and at prices that seemed very reasonable (except, I'm sure, to those who were taking a bath on the sale of the items).

So, you makes your choices and you takes your chances. Do you want to start withsomebody else's dream, or is it worth the extra $$ to start with your own dream? Either way, I suspect you can end up at the same place in the end, it's just the journey there that will be different (and, of course, the cost).

I've already committed myself to building this dream, and I've also realized that no matter what I think I ought to be able to build it for, it will probably cost at least twice as much. But, then again, isn't that pretty much the norm for the kit car industry? From the info in your public profile and your avatar, I would guess you drive a Cobra kit--did you complete the build yourself? If so, think about what you thought you could build the car for at the onset and then what it actually cost. Was it twice as much??? Not trying to flame you, really just curious--this is going to be my retirement gig, so I'd be interested in your experiences regarding this cost issue.

Thanks!!

Doug