Turbocharging Chrysler V-8's Big and Small Blocks

[ChristianCuda]

We have begun and are continuing to discuss how and best ways to turbocharge are older muscle cars.

Turbododge has a twin turbo Challenger 340 already working

Novicious is thinking about Turbocharging his 440 71 'Cuda

Turbo and Novious post and tell us more about your designs or plans.

As for myself I am planning on Turbocharging a built 451 possibly full aluminum engine with twin turbos and home built fuel and spark engine controller with Multiport injection, twin throttle bodies, custom made ram tubed intake, and Wasted spark Distributorless Ignition System all this on my 68 Barracuda

If you have thought about this or are intersted this is the page to discuss it.

This is where we started discussing this topic so for previoous information please read here: http://www.moparchat.com/ubb/Forum14/HTML/000100.html

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68 'Cuda 383 Formula S recreation
Working on adding EFI
69 'Cuda Race Parts Car
76 Duster 273 recent transplant
95 Neon 2.0 SOHC best of 16.96
84 Dodge Ram D50 transplanting 360

[turbododge]

Christian (re previous post)- I think you will be O.K. with the 12 to 15 psi over 9 to 1 compression with the aluminum heads. Probably would be on the edge with cast iron.

I usually run 12 psi over 8 to 1 on 92 octane pump gas. I have water injection that I used to use at anything over 8 psi, but with the more accurate control of mixture that I am getting with the Speedpro EFI, it looks like I may be able to stretch that to 10 without water. The fact that we can again get gas without 10% alcohol is probably also helping.

I think you will probably need a little octane booster or water if you get over 10 psi, but you won't know until you get there. Unfortunately, detonation under full boost is awfully destructive, and can be an expensive way to learn. I have also found that the gas varies a lot in anti-detonation quality, and a 3 to 4 psi difference in the onset of detonation can be seen between different gas sources. I tend to be quite conservative in my setup to keep the 340 from detonating.

[novicius]

<dd>Cool, Turbo -- I was hoping to get a maximum 1.0 bar of boost out of a big-block (16-some psi, I think), so it sounds theoretically possible.

<dd>Fuel quality is probably going to be the biggest issue over time, I think (other than money, of course ). Also, good point about keeping the boost at sane levels. Better to start out at 5-6psi and slowly work it up. I sure don't want to buy an AL MP block and lunch it on my first pass down the quarter.

<dd>I know I'll have the engine work (at least the first rebuild) and most of fabrication done professionally, since I have neither the skills nor the tools to do it...

<dd>- novicius -

[Glen440]

I have always wondered about turboing a big block. What turbos do you use? Can you use a carb? I heard they don't work if you ram air in the top but work if air is pulled through.Where do you mount the turbos? Custom headers?
I think the cost of the turbos would keep me from doing it. I have alot of big block parts so building a couple would be no problem. I have a 8-1 400 that seized a wrist pin I could use as a test motor cause it now needs a sleeve but could be bandaided.
I'd run it on a stand and test its limits before putting one in a car.
Glen440

[turbododge]

Glenn: Here are some quick opinions on your questions.

There are lots of turbos available as aftermarket for $500 to $600 for fresh reconditioned.

You can use a carb, but there are some inherent problems that are very hard to overcome (mixture related). With availability of EFI, I have gone away from carbs.

Suck through carb setups have some advantage in mixture control, But you need a carb that is much larger than normal. At 1 bar you would need 1600 to 1700 cfm on a big block. You also have a long wet flow path that can get puddling and bad driveability. If you get a backfire, it is huge, because of all the gas in the ducts and can actually unscrew the turbine wheel from the turbo. You can't intercool a suck through for the same puddling problems. There are very few suck through systems around any more.

Blow through works better, but requires considerably more work to get the mixtures right. Heavy carb mods are required and some sort of other enrichening is good.

That said, if the car is a race car, tuning a carb would be much easier than for the street as you only worry about full throttle.

I have had a carb suck through system, two carb blow through systems, and two EFI systems.The EFI was by far the best, with the blow through next, and the suck through a distant third.

[novicius]

<dd>Sounds like you've been doing this awhile, Turbo -- what inspired you?

<dd>Back when I was in high school in the late '80's, a classmate of mine spoke about an American supercar call the "Vector", and described what fleeting info he had in very hush-hush tones. Apparently, some cracked Californian had the gumption to twin-turbocharge a Chebbie 350 generating "1,000's" of horsepower and mount it transfersely in a mid-engined car. The thing was generating mad amounts of horsepower and the Germans and Italians were conspiring to keep it from ever seeing production!

<dd>Well, obviously he was wrong; amongst other things, it "only" generated 600+ horse and with only one car ever made for 10 years, the European Supercar-producers didn't have much, if anything, to worry about (would'a been an added bonus if they had used a high-strung twin-turbo 340, tho' ). But still, to a seventeen-year-old kid, it was the stuff of automotive legend.

<dd>

<dd>Ah, well, back to the matter at hand: what or how do you use water in your turbocharging applications, TD? Is that something else to account for in addition to the intercooler, or an additional water reservoir...?

<dd>- novicius -


[This message has been edited by novicius (edited June 27, 2000).]

[bemiller]

What would be a good turbo setup for a bracket racer with a roadster or dragster and a big block. Something reliable and consistent. I've never seen a turbo in one of these cars but I think it would fly! What kind of comp. ratio and boost would be best to really fly and yet be reliable.

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Check out http://www.donet.com/bemiller/ and let me know what you think!!

[turbododge]

Novicius: I grew up with muscle cars (high school grad 67) and by the late 70's/early 80's everything had gone to hell with gas shortages and pollution control vehicles. Some of the factory cars were starting to look at turbos (Mustangs)and people like Gale Banks were selling very high buck conversions and kits.

The standard line among the magazines and hot rodders was that "turbos are too complicated for anyone to be able to build a system at home". That was all it took.

I bought an engine with the remains of an Ak Miller suck through turbo system on it that the guy could not get to run right. Got the suck through working and then converted it to blow through. Both were on the Pinto Holley/Weber progressive two barrel. 16 pounds of boost on 100 octane + water. Later intercooled. 72 Pinto would almost pull the front wheels in second.

Once I had it figured out, I decided to do the V8 and bought the Challenger. Blow through carb first and then 2 different EFI setups.

As to the water. I am using an Edelbrock
Varijection water injection setup. It has been modified to recirculate the water bank to tank until 8 psi of boost when a pressure switch sends the water to nozzles that shoot the water right at the turbine blades. It instantly vaporizes in the low pressure inlet of the blades. I am using the original window washer tank for storage of the 50/50 water isopropyl mixture with the Edelbrock pump fit to the tank.


Bemiller: Consistent launches appear to be one of the difficult parts of running a turbo drag car. As the rpm's come up so does boost and horsepower, so it is hard to hang them on the edge of wheelspin. Some of the GN guys I have talked to try to get the stall of the convertor set so that they have just enough boost built at the line so they almost spin. If you break the tires loose, the rpm climbs, boost goes way up and you totally melt the tires. I am told it is very hard to lightly backpedal a turbo drag car once it has gone into wheelspin.

If you wanted to try it, you might use single turbo, as lag shouldn't be an issue. With a designated drag car, I would think you might want to run 7.0 to 1 compression and somewhere in the 20 to 25 psi boost range. My guess is that you could run on racing gas at this level of boost and get 1200+ horsepower.
It would be fun to see someone do it!

[novicius]

<dd>Single turbo on a V8, how does that work? Only draws off of one bank of exhaust?

<dd>Ok, so as cool as it would be to have a twin-turbocharged, all-aluminum Hemi under the hood, let's approach the issue in separate fiscal stages.

<dd>Putting turbocharging aside for a moment, if I chose to build up my cast-iron 440 (most likely route at this point), using aluminum Indy heads, aluminum intake, and a fuel injection rig of some sort, what sort of options are available for an under-the-hood blower? Vortech? Paxton? With boost running in the 7-9psi range, I know that the fuel system has to be beefy enough to keep the air/fuel ratio at 12.5:1 or less, but what sort of compression ratio am I looking for? 8.5:1?

<dd>Finally, if the LT1/LS1 guys are talking about 440-475 rear-wheel horsepower (accounting for 45 horse lost between the crank and the rear-wheels, more for an auto tranny), what sort of horsepower figures would a Paxton supercharged 440+ cube mill like this put out on pump gas? 650+ RWHP horse? 700?

<dd>How much air/fuel can a 440 take?! We're toying with forces beyond our comprehension! Madness!

<dd>- novicius -

[EDIT: Flywheel vs. Rear-wheel horsepower figures were mislabelled...]

[This message has been edited by novicius (edited June 28, 2000).]

[turbododge]

Novicius: In a single turbo V-8 you use a crossover pipe and run all the exhaust through one turbo. There are some minor efficiency gains to be had with a single turbo, as well as less cost. Most people are now using twin turbos, because the smaller turbos have less inertia and spool up faster and reduce lag. In the drag car lag isn't much of an issue. Take a look a GN for a good example of a single turbo V engine.

In my opinion, the numbers you a stating would be easy to get with a Vortech or other blower, might not even have to intercool to get there. 8.5 to 1 and 8 to 9 psi is very conservative, especially with aluminum heads. You could probably go 9 or 9.5 to 1 and still be O.K.

[novicius]

<dd>Sweet jimmy-jam! 700+ rwhp, here I come!

<dd>So, I have to plan to have a slightly fat fuel delivery system that can keep me peaking at just over 12:1 a/f, running 9.25:1 compression @ 9.0psi, and target 700+ rwhp. Just so as I have a semi-hazy idea what my goals should be, and what to keep in mind when talking with my engine builder.

<dd>Thanks, TurboD, I'm going to chew on this idea for a bit. Man, big-blocks and boost; it was just meant to be...

<dd>- novicius -

[ChristianCuda]

Novicious Sounds real good but for the cost of the blower you could get the twin turbos and the only thing you really would ened to work on would be the exhaust routing.

My motor beign a stroked 400/451 I will be running 9:1 or 9.5:1 so pump gas is able to run on the street. I am going to run something to controll the wastegate so as I can turn it on and shut it off at will. The motor itself will be making 400HP on its own before the forced air with more emphasis on low band Torque. Want to get great launches then get all the power on the top end from the turbos. All I have to figure out is how to get custom gears for the 727 to allow a bigger ratio spread between the gears. As power will be made through a larger stretch of the RPM Band.

8 PSI boost is nothing on the turbos while the drag created by the Blower you lose more HP than it is worth to create the boost.

Keep on the turbo path man.

Christian

------------------
68 'Cuda 383 Formula S recreation
Working on adding EFI
69 'Cuda Race Parts Car
76 Duster 273 recent transplant
95 Neon 2.0 SOHC best of 16.96
84 Dodge Ram D50 transplanting 360

[Stan Cameron]

ChristianCuda, check with Rick Allison at A&A Transmission (317-831-3066) I think he offers different gear ratio for 727s.

Regards,
Stan

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Cameron's Racing
Division of GOTNUTZ?
MotorSports
66 Belv 2 440 auto 10.76 @ 125
69 Road Runner 426 wedge auto 9.74 @ 138
99 Dakota Pro Stock type
truck (under construction)
79 Lil Red Express Truck
96 2500 Ram 5.9
99 Durango 5.9

[Stan Cameron]

ChristianCuda, check with Rick Allison at A&A Transmission (317-831-3066) I think he offers different gear ratio for 727s.

Regards,
Stan

------------------
Cameron's Racing
Division of GOTNUTZ?
MotorSports
66 Belv 2 440 auto 10.76 @ 125
69 Road Runner 426 wedge auto 9.74 @ 138
99 Dakota Pro Stock type
truck (under construction)
79 Lil Red Express Truck
96 2500 Ram 5.9
99 Durango 5.9

[novicius]

<dd>The only reason I bring it up is that with an under-the-hood supercharger, the piping and hookup would be easier, with less to worry about (no intercooler, only one unit vs. two, etc).

<dd>I agree that it isn't necessarily cheaper, since the Vortech kits basically start at $4K and go up from there, but the path has been charted, so to speak, which makes it attractive.

<dd>After surfing around, I found http://www.turbocharged.com/ to have quite a large selection of turbos. Here's a link to one of their catalogs:
http://www.turbocharged.com/catalog/index.htm

<dd>Here's a quote: ...the TO4B/TO4E family can support power levels from 300 HP to 550 HP for single turbo applications and over 1000 HP for twin turbo applications on engines from 100 CID to 500 CID. Sounds like they're talking about us.

<dd>The TO4E Series starts at $730+ per turbo, plus another $600 for the Ceramic Ball-bearing option. So, for twin big-dog packages, that's $3K right there, and much more horse than a supercharger -- you're right, Christian, this is definitely the way to go.

<dd>- novicius -

<dd>P.S. - Christian, check out http://www.gearvendors.com/ also, this is the route I'm going to go with my 727. The base unit, while a bit pricey, can handle something on the order of 1,500+ horsepower (and the Racing version even more!), which should be more than enough to start...


[This message has been edited by novicius (edited June 29, 2000).]

[ChristianCuda]

Novicious I have checked them out before but for what I am think it wont help me.

I want a 3.46 first gear 2.0 Second and .78 Third.

I want the wide spacing because I believe the engine will have a wide RPM band from 1500-6500 for making power. I dont want to go through all three gears by the eight mile and still have half the track left.

This car will be driven on the street and yes those will be harder on the street but on the highway they outta scream especially with that .78 overdrive third gear. If I can I would like to go to a .6 something thrid gear. After this is working then the Gear Vendors unit added ontop would be nice. Especially on the street.

Christian

[novicius]

<dd>What about a Gear Vendors' special order transaxle unit? Again, standard-beefy-issue A727, but with a 0.50:1 top gear? Then, set the linkage up to shift First - Second - First Over - Third - Second Over - Third Over? The 0.50:1 is what the Viper has as it's double-overdrive sixth gear on the Borg-Warner T-56, with a 3.07 rear-end, and even that V10 can't pull it's own Final Drive (it's meant for cruising). Again, handles the horse, has six forward gears, no clutch, full-throttle upshifts, nothin' but net...?

<dd>- novicius

[turbododge]

Hi guys: Just a couple of quickies.

Christian--I can put together a design for variable boost control that is switchable, if you let me know what you need. I looked at it considerably some time ago and have a very simple (adjustable only) setup on the Challenger.

Novicius: I have a source for TO4 remanufactured turbos for $550. I personally feel that the standard, oil cooled, setup is fine, as long as you use good synthetic oil, and pre and post lube. If you were seeing very cold starts, or long periods of high output, it would be a different story.


[This message has been edited by turbododge (edited June 29, 2000).]

[novicius]

<dd>I figured you'd have a better source than the first link off of Yahoo, TD.

<dd>Yep, $1100 is much better than $3K, and for our purposes, we don't need the ceramic ones? Excellent...

<Dd>- novicius -

[ChristianCuda]

Novicious again the GearVendors unit only covers part of my problems which is wanting an overdrive. I also need the 3.+ first gear which the gear vendors unit cant give me. Most 727 come with a 2.46 ratio first if I am right maybe I am wrong someone correct if I am. I need some lower gears but not the whole set. I want a big spread between the gears. Like I stated before 3.+ First 2.0 Second and .7? Third Gear that is rather wide spacing. This is also almost what a four speed will have in it with the third being 1.+ and fourth being .78 I believe.

I want to really torque out of first since the power band should last from 2000-6000 with the twin turbos.

Turbododge does any of this sound right to you? I realized you have the 340 which was mostly top end before the turbos, but do you think the low end torque will carry to the turbo and keep going from there?

On the switchable unit great lets see if we can get to work on it. Send me what info you have gotten started on it. I was thinking somthing like a elctronic vacuum solenoid to control the wastegate. THis would be something simple and inexpensive and driver control rather than demand controlled. Switch would open so that the wastegate always gets vacuum to keep the boost out (or shuts it down for no boost whichever is applicable I am still not to sure on the working of the wastegate) or normal operation.

Christian

[turbododge]

Christian: 2000 to 6000 might be a little wide for full power/boost. The power band has been moved down on the 340, so it very similar to what you are looking at. I just start to get boost at 2000 and am all in by 2500 approx. It does start to run out of wind over 5500. When I was originally setting up, the guys I was dealing with said that a 3000 rpm usable range was pretty typical. My cam was ground 12 years ago, so perhaps newer technology on the grind will take you a little wider on power band.

I think I am missing exactly want you want the wastegate control to do. I was thinking that you wanted to have switchable boost levels (6-10-15 for instance), but now I am not sure. A few more details would help me.

[ChristianCuda]

novicious maybe we can get together with one vendor and buy all four turbos, two for you and two for me, and if anybody else wants one get them in. This way maybe we can get a price break on them. I have been looking at Garrett and Mitsubishi turbos.
Who is the vendor you have been looking at? Some of the turbos I have seen have been in the 300-400 or under range. But these may not be applicable to our motors. I have email all the people that I have liked so far. We will see what responses we get from them.

By the way I am going on vacation for two weeks so I will be in here very little if at all. The same with my email. Vacation starts tomorrow.

Christian

[novicius]

<dd>Ah, I see -- sorry for being slow, Christian.

<dd>Well, if you're running at 14psi on twin-turbos on your 383, I'd have to say that a tall First gear might help the tires grab the asphalt better than a shortie First gear -- but I have *no* practical high-horsepower experience, so basically I'm just flappin' my gums.

<dd>Personally, I'll deal with the tall First, widespread Second, and 1:1 Third, capped with a GV OD unit, since I am shooting for more of a road-race car similar to TD's. The One Lap and Silver State Classic, while still hitting low 11's in the 1/4...

<dd>- novicius -

<dd>P.S. - Well, I'd found the link to a Turbonetics dealer, but TD has a source where he can get them a good $200 cheaper per unit.

<dd>I'll be on vacation, too -- and running up to see TurboDodge during Car Craft's Summerblamarama at the Minnesota State Fairgrounds. I'll take pics (a lot of them) of his set-up (if he's willing ) and put them on my <a href="http://www.novicius.com/rapidtransit/">Rapid Transit</a> site...


[This message has been edited by novicius (edited June 29, 2000).]

[ChristianCuda]

TD on the wastegate control the variable control would be nice.
But what I was refering to was to have a complete cut of boost because this engine will run great with no boost and with boost on it will use more fuel than without boost. So I wanted to completely cut boost for like around town driving. Or when matching up at a stop light not boost rev engine get the guy hooked. Then flip on boost for takeoff. HA ha real sleeper.
The amount of boost would still be controlled by the wastegate I was just wanting something so that there would eb no boost no matter what RPM I am running.
Is this possible with what you know about Turbocharging?

Christian

[This message has been edited by ChristianCuda (edited June 29, 2000).]

[ChristianCuda]

Novicious Sounds good wish I could be there too. I may stop by to see TD on my way back to Texas from MI. We will see maybe we could get together? I will have to see how the whole schedule settles in.

By the way I am still plannign on using a Gear Vendors unit but would like to get the Wide Ratio Trans setup first then add on the OD unit.

Christian

[This message has been edited by ChristianCuda (edited June 29, 2000).]

[turbododge]

Christian: I think I've got it now! Having the boost available (e.g. keep your foot out of it) but not used should give you the essentially the same economy as having it disabled. You have the throttle plates between the turbo and the engine, so they just run a little further closed than normally aspirated. You still get the same intake vacuum at cruise (I run 19 inches at 2000 rpm at 60 mph). The air that is being pumped is getting the energy from waste heat, so the losses are very low. I can get 22+ mpg with the 340 with 12 psi available.

As far as the adustability is concerned, and being able to turn on higher boost, I think the minimum would be about 3 or 4 psi, because you need that much spring to seat the wastegate valve. After that we should be able to give you as many steps as you want, all the way to your max pressure available. I had looked at this system to allow dialing in the boost to match the fuel I was running. It should be readily doable.

Novicius: I am working on a slide show screen saver of old work in process pictures that I am scanning. I want to have it on the computer at the show. If I can get it done, would you like a CD of the pictures?

[novicius]

<dd>Absolutely, TD.

<dd>I didn't want to say anything, but I was pretty sure there's a minimum amount of boost that needs to running with the TT setup.

<dd>Speaking of boost, check out this crazy Supra TT on a dyno:

<dd><a href="http://members.xoom.com/Lil4cyl/bryced~1.mpg">http://members.xoom.com/Lil4cyl/bryced~1.mpg</a>

<dd>Pretty good -- but we should be targeting for about 200+ more horse, eh?

<dd>- novicius -

[This message has been edited by novicius (edited June 29, 2000).]

[ChristianCuda]

TD: If you can get me a copy of it I can set it to and AVI and also to VHS Tape. SO send me the pictures and presentation on a CD also if you can.
Or if I get over there I will pick it up from you.

Christian

[IndyRam]

A couple of things to consider:
Please excuse the underbars, it's hard to do formulas in this editor.

(P1)(V1)___(P2)(V2)
-------- = -------- or
___T1_________T2

P1___P2
-- = --
T1___T2

For engines, since the volume for the intake track is constant in this case.

P = Absolute Pressure 14.7 psia (absolute) = 0 psig (gage). Hence, it you could maintain mixture density at elevated temperatures 14.7 psig boost would double the horsepower.

T = Absolute Temperature in degrees Rankin. Farenheit degrees + 460.


When you run the calculations, 1 atmoshpere of boost with a inlet air temp of 90 degrees
will yield a cylinder inlet air temp of over 300 degrees; if memory serves. It has been 20 years since I messed around with turbos, back then almost everyone used Air Research or Garrett. BTW the turbopumps we use on the Shuttle can empty a standard swimming pool in a few seconds.


[This message has been edited by IndyRam (edited June 29, 2000).]

[turbododge]

Indy: Exactly correct, pressure times volume is constant at constant temperature (for a fixed mass of air). The actual formula that this is based on is

PV=nRT

if I remember right, where n & R are constants that define the total number of molecules (mass) present. This is the formula that shows how high the temp goes up when you compress the air mixture. As you said pressure up in constant volume drives the temp up. So if you heat the air as you compress it,it takes up more volume, and since the inlet is open back to the turbo at constant pressure, it gets less dense as it fills the volume. That is why you intercool the air to get the density back up. Good intercooling can get the charge temp down to decent levels, but you usually don't get as low as the turbo inlet.

Because of the lowered density of the charge air, and the restriction of the exhaust by the turbo under boost (exhaust pressure runs about 3 times the boost pressure) which doesn't let you get a full cylinder charge, you don't actually get double the horsepower at 2 bar (29.4 psi) that you had at one bar, but you can get close. Even with these inefficiencies, it is a very efficient to generate lots of horsepower.

Christian: I did manage to burn a CD tonight with my history pics on it and get into the laptop slideshow. If you make it by, I will get you a copy. If you do manage to come this direction on a weekend, we could save you some travel and meet you in Madison, if Novicius is up to it.




[This message has been edited by turbododge (edited June 29, 2000).]