The TT post on the Superram with TT got me to thinking, how much to turbos cost?
how much more power can you put down with these things?
Could you use one of these SR-TT cars as a daily driver?
Would you have to change gears and/or get slicks to drive one of these things?
What about a cam change? would it be necessary to use the power?
also where do you put the damn thing on a vette?

sorry guys but i'm still learning about the internal workings of an engine and i dont know jack about SC's and turbos

 

is there anywhere or anyone that has a picture of the Sledgehammer engine so i could see how its set up?

 

I have been looking high and low for pictures of the sledgehammers set up for years!

This is it:


Tight fit.
Now the Callaway TT's sold to the public have a different turbo set up. In the same location, but not as big on the turbo, the exhuast is a log style manifold, not headers like the Sledgehammer, just a bit more of a cleaner install on the cars sold to the public.

here is the top:


Those are the intercoolers in front of the motor, not the radiator. The radiator is layed down flat underneath the intercoolers...

Here is another shot of the Sledgehammer engine.




[Modified by bill mcdonald, 6:55 PM 1/24/2002]


[Modified by bill mcdonald, 6:55 PM 1/24/2002]

 

Yes I have some info on this as I have been planning this build for a year. The sledgehammer used T04B Turbos, they had to drill 4" holes in the frame for these and they picked the air up in the side gills. They had to relocat the battery and the A/C box in order to do this. No one at Callaway will help you, the answer I got was that nobody works there now that worked there then. You can call Turbonetics and get two 60-1 HyFi and the Race gates for them for $2600. Depending on your setup with engine and such, you will need DFI,and a nice bottom end and heads, I would suggest a SR also or a custom intake. Once you have the engine in, you can take your car to Kooks Custom Headers in NY and the can fabricate everything for you. This is where is costs $$$. You can figure about 6K. That gets you a running car when you pick it up including the intercooler. It all depends on how much HP you want and what you use in the engine. I built mine on the mild side, it is still very far from finished and should make over 1100HP at the rear wheels with 28lbs of boost. Yes it will drive like a stock vette when cruising.

 

How far along are you?

 

Well not as far as I would like to be. I have lots of pieces but I am actually building a in between motor to get me around. I have been doing lots of chassis mods. I have my diff down in FL going through cryo, Once I get the chassis done and my wife off my back I will get back on finishing the motor and setting up the turbo's. The 60-1Hifi my still be too much for what Vader86 is wanting to do. My goal was to show up in Carlisle next year and peg the dyno. So I won't be happy until I can do that. I don't talk much about what I am doing because it is taking so long. If you really want to get some advice on doing something like this I suggest you talk to Dan Baldwin at Baldwin Automotive in Va. 804-598-7727. He just finished his 69Z28 last year. It is a single T76 Turbo with a 355 small block. The car has already turned a 9.62 without leaving on the trans brake. It really suprised allot of people at the track, flat hood and very quiet.

 

I am in the middle of an intercooled, twin turbo project right now. My car has been down at TRZ Racecars for almost 2 weeks now getting the headers, intercooler, cold air intake, and exhaust done.

There are alot of options and decisions to be made when designing/fabricating a custom turbo setup. Selecting the turbocharger size and design is the easy part, once you've determined your performance goals and whether you want single or twin.

The right way to do it regardless of whether you go single or twin is to use an aftermarket programmable engine management system like the FAST/SpeedPro or Accel DFI. Additionally, I wouldn't even consider a turbo setup unless you are going to intercool it.

I figure that if I'm going to do it, I might as well do it right. You can save a bit of money by fabricating your headers out of mild steel for instance, but they are not going to last as long as stainless steel. Even for custom mild steel headers, you're looking at almost $2000. I figure that if I'm going to spend that kind of money, I'd rather pay a little more and go with stainless steel. I went with .065" (16 gauge) 321 stainless steel. It's a little more expensive than 304 stainless, but it the recommended material for a turbo setup. It will last longer and is the best material, short of Inconel (which is even more expensive). The material costs add up quick, the material costs for my setup are almost $6000 for the headers material, the intercooler core, the aluminum tubing for the cold air induction, and the 3" 304 stainless for the exhaust, plus Borla stainless XR1 mufflers and a blow-off valve. For the whole deal, TRZ estimates 120 hours. I called around to some other shops, including Troy Trepaniers shop Rad Rides By Troy, and they all had around the same estimate in terms of time. Rad Rides is the shop that did John Meaney's car, and they are arguably the finest custom car shop in the country. Total cost for the fabrication of the headers, intercooler, cold air, and exhaust is a little less than $16,000. Plus the turbo's and waste gates were another $2000.

It's an expensive power adder, but the results are worth it if you want that kind of streetable power. You can realistically make up to 1600-1700hp and still be totally streetable. A good turbo engine is actually very mild until the turbo's starting making alot of boost. Mild, stock type cams are actually the best cams for turbo's. The popular thinking is to keep the overlap at a minimum which tends to give an engine very good throttle response and good off idle torque. Add in the CR which you want to keep below 8.5 if you want to run much boost without risking detonation with a street tune and pump gas. So the engine will idle very smoothly, and have very streetable, responsive, torquey performance before the turbo's start making boost. Once the turbo's start making boost, hold on! Turbo's have the ability to go from 0 to maximum boost in a fairly narrow rpm span - around 1000rpm or so. Turbo's are load dependant, rather than rpm dependant, so depending on their size and design they make for a good street power adder.

John Meaney uses his 1300hp C4 Corvette as a daily driver, when it's not raining. Mine won't be a dialy driver, more of a weekend and evening street machine. But I drive it to work every once in awhile when the weather is nice.

As with any other engine modification, you will need to address the rest of your combination if you want it to be successful.

The packaging of a custom turbo system in any car not originally designed for it is all about compromise. There are few cars that have the engine bay room to fit it all in without relocating things or making compromises in some ways.

I am having my setup built almost idential to John Meaney's. As KArl mentioned already, the forward high mount setup does mean accessing the sparkplugs means you'll have to do it from below, but that's pretty common these days anyway. I have seen some setups where the turbo's are mounted above or next to the valvecovers which is not desirable in my opinion. It would be a pain to have to remove the turbo to remove the valve covers.

The low mount setup like the Sledgehammer addresses this issue, but it does mean that you will need to add an oil scavanging pump to your system since you can't rely on gravity to drain the oil back to the sump. This is a critical aspect of a properly designed system. The seals used in the trubo are not designed to be saturated in oil. If there is too much oil, the oil will get past the seals and into the turbo housing, creating alot of smoke and sending oit into the intake tract. As we know, when oil gets into the combustion chamber it has a tendency to induce detonation which the enemy of forced induction. Conversely, if the scavenge pump is too effective, not enough oil gets to the turbo bearing before being pulled back into the pan - this is why a large 1/2" drain line back to the pan is the best method. Additionally, the low mount setup exposes the turbo's to more road debris and risk of damage. The turbos are precise devices and damge to the housing can affect the clearance beween the turbine/compressor and it's housing.

Also, don't get caught up into boost numbers. They are a poor indicator of the performance of a turbo engine. Boost is nothing more than packed air in the manifold. The point is to get as much air/fuel in the combustion chamber, not the manifold. As with normally aspirated engines, cylinder heads make all the difference. A high flowing, efficient cylinder head will allow an engine to make as much or more power than an average set of heads with more boost. John Meaney's engine uses 18* heads similar to mine, and he is making almost 1300hp with relatively low boost, only 15psi or so. Running boost levels like that means you can make your targeted power with less risk of detonation. Of course you can run more boost by adjusting the wastegates, as long as your fuel octane and tune up are sufficint and make more power, but you're still ahead.

On a street tune and pump gas, I'm targeting 1200-1300hp on pump gas, reliably.






[Modified by Monty, 8:47 PM 1/24/2002]

 

Monty I have been following your buildup. I jealous, I wish I had the money to go out and get all my stuff now. I have been working on this for over a year and it is still at minimum going to be another year before I really get rolling on it. I have a DFI now, but I will be upgrading it to a GEN VII. I chose to mount my TT below and run a oil pump. I just could not see that much heat close to the hood like in Meany's car. Kinda sucks cause I thought I would be the first with a street legal C4 with over a 1000 horsepower. Oh well. I am glad that I see my thought process was at least the same as others. Did you try contacting Kooks Custom Headers, they do allot of Turbo fabs. My buddy Dan's Camaro was done by them and he also went with the forward mount headers but with a single turbo.

 

There's more than one way to do it, that's for sure. It's just a matter of weighing the options and applying your own priorities. Heat is obviously a key consideration. I talked to one of the guys at Rad Rides that worked on John's car for about an hour and I mentioned the heat issue. He said it isn't as bad as you'd think, and as you can see from the picture, the down pipe goes though the inner fender and is very close to it and the hood seals. They told me that John has driven it down form Detroit several times, as well as just normal daily drving and they haven't had any heat problems. I'm planning on having the headers, the turbine housing, and the down pipe coated. The thermal coatings can reduce the outer surface as much as 300F, and any heat shielding is part of my deal. Turbonetics also offers a fitted thermal blanket, kinda like what people put in starters, for the turbo's. They say that will help reduce the underhood heat alot, as well as help turbo spool up a bit. If Kooks is local to you, you're lucky as well, cause I see alot of their work in the NMCA/NSCA/NMRA cars, as well as Fastest Street Car and Race Pages.

Even if you aren't the first 1000+hp street legal C4, you're still be one of the only. Good luck with your project, I'd like to see pictures if you have any. As with any custom setup, there are many ways to do it right, and it takes alot of creativity. You should take a look at the Thirdgen and CamaroZ28 web sites. There are several guys over their doing custom turbo setups with good pictures. They are good to look at to get ideas, and see what works well, as well as learn from their issues and mistakes.

This has been an ongoing project for me as well. Building the engine alone was almost a year. I didn't even get to drive the car until last November with the SBC 427. Things like this take time and I don't know too many people who can just write a check and get it all done at once. I sure can't, that's why it gets spread over 6 months. I sure ain't going into debt for it, or quit saving/401k/IRA, etc.

I wanted to stay with someone local, and luckily there were a couple of good choices here in Chicago. I thought about Kooks, but I just felt better having someone do it who could have my car. I felt good about TRZ because they do alot of work on the guys' at Fast Times cars as well as their customers. Tom has been doing turbo setups for the NMCA/NSCA/NMRA for several years now, so I know he knows what he doing, and his work is always looks good.

 

Thanks for the reassurance Monty. It looks as if it is going to be awhile. I have a engine I putting in right now that makes good power until my tt motor. I found a deal on a vortec so I'm thinking about running that for a year and then sell it when my tt project starts getting a little farther along. Kooks is not that close to me, I am in Richmond, VA but I was going to trailer the car there. Dan is trying to talk me into mounting them forward, but I still like the idea of them kinda being out of sight. Justin

 

The closer the turbo's are the the head, within reason, the better. Rmember that it is the exhaust energy which is what drives the turbo's. The farther the turbos are from the exhaust ports, the more the exhaust will lose heat. However, if it needs to be done that way for packaging reasons, I wouldn't worry about it. Heavier gauge tubing, thermal coatings, even thrermal wraps will help retain the heat and get more of it into the turbos. Keep in mind though that although there may appear to be alot of room there, remember that not only do the turbo's mount to the end of the header collector, but you'll have a 3" or so downpipe/exhaust pipe, as well as a air cleaner and any sort of cold air tubing there as well. This stuff stakes alot of space, cuase you don't want to run a tight 90* turn or more right out of the turbo for your downpipe. Doing so would increase backpressure right out of the turbo and this would negatively affect the ability of the turbo to spool.

Also, consdier that the turbo's, wastegates, and intercooler - along with all of their tubing and ducting, can start to add up in weight. Having all of that weight at the very front of your car could really have an impact on your cars handling.

Hey Karl, don't balme me man. I'm one of the victims here, a victim of a terrible, terrible disease. The Need For Speed....

 

If you do a Twin Turbo on your car.. you won't need a ZR1 :D

 

Hey Jeff, how's the 50H81? I did the 9pt convergence Wedensday night. They were mostly all aligned. I was surprised to see that you don't align green. I'm still reading the service manual to see about the 56pt convergence thing, and I'm going to pick up the AVIA disk tonight.

After finding that forum, I was worried I'd find all the flaws thsoe guys were complaining about, but I couldn't find them. It still think it's an awesome picture!

 

Karl,

Check out Precision's site, they have their catalog of turbo's, listing the size, the hp output, and the requirede stall - http://www.precisionte.com/cgi-local...712829.4794742

Looks like the smallest is the TA 32. They say one of those is enough for 460hp, so with two, you're looking at 900hp or so, plus they spool up quickly, needing only a 2400rpm stall. But I think they would be too small, and the throttle would be too responsive. You'd have a hard time getting ti to hook, becuase it would make so much torque off-idle.

 

Mounting turbos under the headlights is not really going to work out (I was looking into this as well). You would have to butcher the car to just get a turbo in there. then you need to mount an air filter and the down pipe in there too. The frame rail does not help things at all, and if you could get the turbos down in there, you would probably need a scavenging pump to get the oil back into the pan.
Mounting the turbos under the car seems somewhat easier at this point, at least the exhuast has a straight shot out the back of the car.

Now mounting the radiator and AC condensor flat might work (lots of room there), but where would you mount the intercooler, and would the cooling system suffer at all? You might need to put 2 holes through the frame to route teh exhaust out of that area to the back of the car.
Callaway cut holes in the area where the front mono spring went on the TT ZR1. They had coil overs on the car to do this.

I gave this some thought as well, if you ditch the AC, and move the alternator up to where the smog pump is, you can probably mount both turbos at the front corner of the heads, like the F-body TT super ram car monty posted pics of did. (where a supercharger would be). This would eliminate the scaveging pump as well, plus you could put 2 holes in the hood to ram cool air straight into the turbos, mount the intercooler where the AC condenser was.

Only problem I see with this is the Down pipe, It would probably fit a 3" pipe, but not allow you to get the the spark plugs very easily.

I have bounced back to the idea of them going under the car.
I figure you could move the oil filter to somewhere else to free up some room, but I would like to see a way to mount the starter behind the bell housing. this would leave tons of room for bigger turbos...

 

I love the 50H81. I don't have Digital cable yet (coming out on Sat) so the analog cable is a bit grainy on some channels.. Otherwise DVD's Look AWESOME.. I myself have not done a 56pt convergence.. won't for a while. Like you I am going to limit my reading there and just enjoy the nice big Picture.. and to me it looks larger since it replaced a 25" LOL

 

Who says the exhaust has to go out the back? Cut a hole in front of the wheel wells for those 3" downpipes to come out of, that would be bad to the bone. Back in the day the only guys dragracing with turbos had there humongous 4 or 5 inch pipes dumping somewhere in front of the wheels. Come one guys, since this is all custom work anyway lets think outside of the box. Now I'm thinking exhaust out the hood....oh my..... :crazy:

 

Going to do that but with cuouts so I can " whisper" past cops

 

Keep in mind that the turbochargers have a dramatic dampening effect on the exhaust. Alot of racers in the 'street legal' series don't even run mufflers and still meet the db requirements. If you're expecting a loud, thunderous exhaust note form a turbo car, you may be slightly disappointed.

 

Yes I know that turbos do quiet your exhaust alot that is what would make dumping it in the front easy because you wouldn't have to run mufflers.