Turbocharging a Superformance Big Block???

[fordracer]

Has anyone here successfully put twin turbos on a 460/514 in a Superformance roadster???? If it's been done what kind of body/underhood modifications were needed???

[ffindling]

It can be done, but not easily. Probably the biggest challenge in such an
installation will be the intercooler setup. It has to go in front of the radiator
and there isn't much room there. Since you want twin turbos, the intercooler
will have to be a two-section unit with separate intake/discharge connections.
The intercooler will probably have to be custom built for your application,
a number of shops can do this, but it will be pretty expensive. A larger water
radiator will probably be necessary as well as it is going to be deprived some
cold air flow going into with intercooler sitting in front of it and fitting a larger
radiator will be challenging as well with the air plumbing go to and from the
intercooler taking up space where the radiator resides. Custom headers will
be needed to route the exhaust gases into the turbos as well as some custom
plumbing to route the turbo discharge to the sidepipes. Assuming you will be
using EFI, you will need to make sure whatever ECU you decide on supports
a twin turbo installation with electronic wastegate control on each side.
I believe the Electromotive TEC3r can do this but there are probably others
that can as well.

....Fred

[ByronRACE]

The turbos need to be above the oil level unless you're going to rely on some kind of external scavange pump to lift the oil back into the pan.

If you're turbocharging a 385 series, you obviously want more than 800rwhp, so you'll need a pair of turbos that are quite large in size...like a pair of T60's or something similar.

Take a look at a 385 based SPF. Those turbos all by themselves aren't going in the engine compartment; let alone the plumbing. So, they'd have to go somewhere else...like probably up in the nose behind the headlights or behind the tires in the front fenders somewhere. You'd have a real problem on the drivers side with steering, brakes, etc... I think you're going to have a major packaging problem. And, we havn't begun to talk about the plumbing/intercooler.

If you're willing to stick them through the hood and make a "log" style exhaust manifold, you could simplify the plumbing a lot and make it happen easier...but it won't be too pretty; unless that's the look you're going for.

A single turbo low and in the front would be an easier solution. Or a supercharger with a mount like mine. The same basic configuration could be accomplished with a single turbo and some front-swept exhaust that comes to a shared collector right at the turbo.

It'll tend to kill your exhaust note...turbos quiet an engine a lot. Be aware of that up front.

And, with a turbo, you'll need an intercooler. Turbos generally use smaller impellers spinning at higher rpms and create far more intake heat at a given boost level. Even at 8psi or so, I think you'll see 200+ deg intake temps without an intercooler; that won't work well.

Personally, after having gone the power-adder big-block route in a Cobra, I'd advise you against it. (A) It's ludicrous and largely unusable. (B) You can build a little 545 stroker with some A460 heads and make over 750hp to the tires on pump gas...how much power do you want?

My tires are on fire at freeway speeds at right around the 500hp mark (per my datalogger)...beyond that, I don't see the point except for the cool factor of having that capability. It was/is cool; granted; but the wow factor wears off shortly after you've done that a few times.

My stuff is at http://www.racesystems.com/cobra if you want to look at it for ideas.

Oh, and I should mention...my car is an old West Coast Cobra. I believe the engine bay is longer than SPF by about 4-6", and there's a lot more room in the fender wells.

[ffindling]

Originally Posted by ByronRACE

And, with a turbo, you'll need an intercooler. Turbos generally use smaller impellers spinning at higher rpms and create far more intake heat at a given boost level. Even at 8psi or so, I think you'll see 200+ deg intake temps without an intercooler; that won't work well.

I agree 100% there, to use any meaningful boost pressures, a pretty stout
intercooler system will be required and packaging that in the confines of an
SPF or just about any other replica is going to be extremely difficult and expensive.

....Fred

[mike knight]

my experience with installing a turbo in an spf may be of interest. i have a 351 windsor with a 93mm intercooled turbo. i actually bought 2 56 mm turbos as that was my intent. we could not lay up a plumbing system for the intercooler and turbos in the engine compartment. we had made arrangements with the supplier to return the turbos if we couldn't succeed. there simply wasn't enough space for all of that 3" piping and intercoolers. i even went to an electric radiator mount water pump. after a considerable amount of work we decided to go with the single turbo.
i have also experienced cooling issues. my car in traffic on a hot summer day wants to run over 105 c, about 220 f, and would probably continue to climb slowly. on the highway it runs perfect at about 180f. more work to be done with the cooling system over the winter. you can see a couple of pics of my installation in my gallery. i know you are asking about turbo installs for a 385. i can only imagine you might have the same issues as i with my small block, only compounded by the size of your motor and exhaust system.
i will say that performance with the turbo at about 30 lbs of boost is insane. i am driving on the street with about 7 lbs of boost and acceleration is very quick. in third at 60 mph if you stand on it the rear 295's break loose. at 140mph in 6th it pulls hard. turbo whine is very pronounced. mustang dyno with 7 lbs of boost equals 596 rwhp 4800 rpm and 613 ft lbs at 4250 rpm.
incidentally what you see in my pics was expensive. fyi

[fordracer]

In all honesty I do not have a Cobra yet. Long story short I have wanted a Cobra for the last 29 years.

Now that I have some money I am trying to decide what I want. Fortunately or unfortunately I have had many years to build a perceived notion of how a Cobra should run. As I've gotten older my tolerance for all out race cars on the street has dropped.

This leaves me with a choice of buying a used ERA, and its possible inherent problems. A new Superformance. A new Dodge Viper or a new Z06. Again to be brutally honest, a Viper and Z06 with factory 500hp,a warranty, and everyday reliability sure looks good. Add to this the relatively cheap ways to gain even more power from the Dodge or Chevy is an even stronger argument.

But, compared to a Cobra there are Vipers and Corvettes on every corner. I could buy a used ERA, sell off the FE that it came with to fund a new motor of my liking or, buy a Superformance and also have a motor built to my liking.

I picked twin turbo because I was only thinking of the side pipes. If a single turbo is easier to package then I will do it. I don't want a centrifugal supercharger because I like the explosive acceleration a well set up turbo can give. I was also thinking of using the turbos as my mufflers. I have read too many threads on how restrictive the exhaust is on these cars. It doesn't turn me on to build a 500+ hp motor only to have it choked by something as silly as a muffler.

Thanks for the responses

[Excaliber]

If you plan to dump the FE, ERA is not the car you want. Get something that isn't known for being as 'correct' to original specs and modify it to your taste. Something like an SPF or an FFR would be more suitable as they typically come with a wide variety of motors anyway.

[decooney]

fordracer,
IMO - unless you are going to turn it into a full-on drag car/suspension setup and race it, why so much power in a 90" wheelbase / IRS based car on the street with street tires? If you've never driven a hi-powered 700+HP Cobra on the street before with an IRS, get ready for a ride or a wreck! A close friend let his other friend (7-time NHRA World Record holder) step into his 580HP Cobra and he didn't last 5 minutes before he put it through a few fences and almost killed himself. Bad ass drag racer almost lost his head, literally. He quickly found out first hand why Cobras can bite you.

Another buddy just finished a brand new SPF 542 stroker for a customer, at 700HP. He kept trying to hint to the customer it would not be what he thought it would be. Customer had to have the biggest/baddest; so he proceeded. We all just sort of laughed shaking our heads, sat back and waited for the phone call to come in. Sure enough, didn't take but a few weeks, now the customer is reportedly selling the car becuase its a bit too much and not that easy to drive without swapping ends. Seriously, my friend says at any speed the thing just fries the tires and can get out of control quickly. Its a normally aspirated 385 series / 542 crate motor. The customer now wishes he had a 351 in his car. Oh, by the way, an ERA with 550+HP gets to be pretty useless if you ask me. That's about the limit. I spent months building/testing stronger diferential/ traction system that helps but its still and IRS. If you go 385 series, the SPF would be a better car to try that in my opinion.

I say go Drive or be a passenger in a true 500+HP (90" wheelbase) Cobra and experience it first before you decide to build an overpowered out of control 385 series monster with turbos. Good Luck.