Bring on the boost!!!!! Time for a change
 

I have had nitrous on my Pontiac since I was 18 years old. As of tomorrow morning my tiger headed nitrous huffing engine will have a new home. And I will start my twin turbo build.

Somewhere along the way, I lost what I loved most about my car. The ability to drive it anywhere. While I drove my car a bit this year, it was not near enough and I was worried about valve springs and fuel the whole time. Plus with a passenger, the bottles have no place to sit. Its just not as fun anymore. I want to go faster, but I want to drive it as well. And with all this engine bay room, my car is just SCREAMING turbo.

So this is my thread that I will document my build from start to finish.

MISSION OBJECTIVE:

Drive my Pontiac WITH A PASSENGER to my local race track, run a 7 second pass and drive it home.

Any input, ideas, suggestions, parts, sponsors, and trash talking is all 100% welcome in this thread. As of right now this is all I know.....

It will be pontiac, it will be turbo, it will be injected. Other than that, I am all ears.

BrandX Your best bet is to talk to Tom Vaught. He is a guru, when it comes to boost. Thanks Rusty

Great idea. Can't go wrong with turbos and street manners. Good luck on your build and I'll be watching your progress. I'm looking foward to this. Mark L

Awesome!

What I can tell you is that traction and boost management are definitely important.

Making enough power with a pair of 88's will definitely not be a problem to get the job done.

The turbo route once complete is really the better choice as far as I am concerned.

Looking forward to the build info.

Just for grins, BrandX, post up your weight and the assumed cid & heads of the new engine.

Your car's photo looks like a nicely built "door car" vs a full chassis car. Say it can get down to a 3000# weight (with driver):

Wallace's calculators says "Your HP is 1,162.44 computed from your vehicle weight of 3000 pounds and ET of 7.99 seconds."

To run a legit 7.49, "Your HP is 1,411.12 computed from your vehicle weight of 3000 pounds and ET of 7.49 seconds."

So IF we assumed 1500 hp as a target, you get: "Your ET / MPH computed from your vehicle weight of 3000 pounds and HP of 1500 is 7.34 seconds and MPH of 182.56 MPH." A solid 7 second performance.

So say we assume a 1500 Horsepower target.

A typical engine will make between 9.5 hp and 10.5 hp for EACH "pound of air mass" flowing thru the engine in ONE MINUTE. Not cfm, AIR MASS.

so:

1500 hp divided by 9.5 = 157.9 lbs per minute of air required.
1500 hp divided by 10 = 150 lbs per minute of air required.
1500 hp divided by 10.5 = 142.9 lbs per minute of air required.

Worse case (with a cushion) would say we design for 160 pounds of air mass per minute turbo system. If you want a CFM number: The conversion formula from cfm to lbs./min. is to multiply or divide by 0.0691 depending upon the conversion direction. So we divide 160 pounds of air mass per minute by .0691 and get 2315.5 cfm.

We then go to the Turbonetics site:

http://www.turboneticsinc.com/content/compressor-maps

And we look at the "HP76 Turbocharger Map" as an example: (it is the first large map after you use the link).

It shows that under best conditions we could move 80 lbs of air per minute from one HP76 turbocharger at a little over 20 psi of boost (2.4 pressure ratio on the left side of the map and "80" at the bottom of the map. The compressor efficiency would be about 74%. If you wanted a bit more efficiency you could step up the Pressure Ratio to 2.8
and be in the 76% efficiency island. In reality the maps are typically not perfect as far as efficiency numbers go vs mass flow numbers which are more accurate. mass flow makes power, lower efficiency numbers raises the air temp going into the engine slightly. So you would need TWO HP76 turbos to make about 160 lbs of air mass per minute. You would have a lot of cushion if you only needed 143 lbs of air mass per minute.

A pair of Y2K Turbos (T-88s) would make well over 2000 hp at a 2.4 pressure ratio:
http://www.turboneticsinc.com/sites/...T-88%20Map.jpg

Looking at the Turbonetics catalog:

http://turboneticsinc.com/forum/turb...11_CAT_LOW.pdf

If you look at page 17 of the catalog under the TN series Turbos you will see that the HP76 Turbo is rated at 1000 hp per turbo. lots of room to make power.

TN1000-BB 1000 (Horsepower) HP76 Super-T 4.5"/3.0" F1-68 T4 .96A/R 4-bolt/V-band n/a 11530-BB

That would be my first estimate on how to make your goal.

A Single Turbo Installation using a HP-106 TNX turbo (same basic size as John Welters deal) as we know will make excellent HP and run 6.80s (which John W has done several times).

HP-106 30649 5.50" 20737 (11175 TNX0106 1.32 A/R 1750 HP+)

Tom Vaught

ps the Turbo is just a small part of the whole deal though.

Travis Quillen would also be an excellent resource for this project.

calculations
 

Hey Tom, These same figures can be used when figuring on blower size too Correct?? for CFM requirment?

Excellent reply Tom. Part of the planning should also include type fuel intended. Intercooling and water injection are part of the picture. If pump gas, the practical/probable pressure ratio has to be taken into consideration when choosing the turbo. If for example you set an arbitrary boost psi of say 15 , you need to choose a turbo that can meet the mass flow requirements of the HP desired at that psi level while staying out of surge zone or getting into choke.

I'll also add that you wont need maximum bore size or stroke to acheive/exceed your goal. (Or turn very high rpm for that matter).

I like your goal though. I'm not looking for your ET level with my build but I too like driving my car. Would love to drive all the way to Norwalk run some respectable numbers and drive home. Turbo gives the motor that flexability. The real challenge for me will be keeping the chassis combo flexible enough for a 1000 mile round trip and still be able to run quick numbers.

Good luck with your project I'll be following it closely.

It looks like the turbo conversion is spreading. I'd be watching your build as you always build a Bad Ass setup. Good luck.

Forgot to warn you turbos can be like crack... once exposed you are hooked forever. My first introduction was in 68 when I took a ride in a friends 65 Corvair Corsa turbo. (An animal compared to my $35.00 road rat standard Corvair I was drivin a year later) Left an impression for sure.

Woo Hoo, Go for it BrandX

Many of us have seen this video here, Larry Larson's 6 second Nova & Drag Week winner

http://www.youtube.com/watch?v=lwF-kr91uxU

X,

Mike Moran now has the ability to tune at any dyno in the word from the comfort of his hometown chair. I would love to see what he can do to a Pontiac. You sir, would be a perfect candidate!

On a side note, I've been following the progression of your car and dig it all! I am however, partial to satin black 70's ;)

Good luck on the build and look forward to hearing how it all comes together.

Agree the Surge Zone, see compressor map for HP76 , can be pretty far to the right on some larger turbos. Fortunately if you look at the HP76 (see link above) you will see that at 10 psi of boost (bottom red horizontal line on the map) you are well to the right of the surge line at as little as 25 lbs per minute of airflow (250 horsepower). Any Pontiac will make well over 250 hp at 10 psi of boost due to their cubic inch size. So the only surge that you might get is if you sized the compressor by-pass valves too small and can't dump the air fast enough when the throttle blade is slammed shut on a quick back-out of the throttle. The wastegate will not help you much there in the first 100 milliseconds of the throttle blade being closed. A GOOD compressor by-pass valve will open in about 32 milliseconds.

It turns out that this guy has one of the best CBVs out there:

http://www.spike.com/video-clips/cw7...mpressor-surge

Great video explaining the difference between a bad and a good CBV valve in his video.

Tom Vaught

boost
 

its not just Turbos that are addictive. It's the Boost!!!!!!! with the power that can be made with turbos and blowers today its just awsome.. Following what Tom posted 3000lb car goal 7.50 its exactly what my goal is. So look foward to spring. Gonna have some fun.

Yes, the Mass Air side of the deal is the same. The problem is most supercharger guys do not have a Supercharger Flow Stand. Therefore no accurate maps to go by. The only supercharger company I am aware of in the Hot Rod industry who has a flow stand that can do accurate mapping is Vortech/Paxton Engineering located near the Channel Islands, in California.

The efficiencies on a roots type supercharger are also pretty low therefore a lot more heat made and most do not run an inter-cooler after the supercharger.

That being said, the people making superchargers for the Big 3, typically use the factory production boost parts. The 2004 Cobra Mustang is a production example where Supercharger companies offer larger superchargers that bolt on to the factory intake manifold. Vortech/Paxton again makes all their own stuff for the OEMs.

So to say that the supercharger can be figured the same way? Yes if it is a Vortech/ Paxton Supercharger. If you have a Procharger you take their advertized flow numbers and hope it works. Typically most over-build when using the Procharger stuff because a F2 that makes 1400 hp on one engine will make it on a different brand engine. Only deal there is you have to subtract out the power it takes to spin the blower. With the turbo stuff you are using energy that normally just goes out the headers.

Tom Vaught

Obviously I wanna go faster than 7.90, but small achievable goals with an overbuilt combo are easier for me to shoot for hahaha. The nitrous combo weighed 3400 lbs. I have no pieces of the puzzle yet, and I have a call in to Travis q and he will be calling me next week with an initial gameplan. Starting from scratch I am hoping we can build it right the first time, and build it around my budget instead of around my parts (usually what I end up doing)....

I can't wait to hear back from Travis q do I can get a head start on the engine. I will be building everything myself from start to finish. I have never welded in my life, and I am going to buy a welder and teach myself to tig weld. I want to be proud of myself and my car and our goals accomplished together.

Looking forward to watching your progress. Good luck!





Bryan

Subscribed....This should make the winter go fast!

Welcome to the club BrandX!
Tom and Travis are great guys to consult with. For what you’re going to save fabricating your own headers, you’ll be able to get a really nice TIG welder.

A Company that does fabrication stuff for me taught one of my summer high school interns at Ford how to TIG weld in one afternoon. Kid did a nice job on flat stock.

Course the machine was set perfect for the welding process.

I can get you "numbers" for a basic Header welding type process and the purge gas that they recommend for the stainless type IF you tell me the machine you will be buying. Don't even think about trying to make proper headers without the purge welding process (separate gas tank fills the header tube to remove internal slag formation).

Tom Vaught

welding classes
 

that reminds me of taking my welding classes back in the day at College of Lake County Gary one of the instructors and a fellow racer had us working on his Nova for the class project. Showed us about filling the tubes just like your talking about Tom for doing stainless headers. If I remember correctly think we used a Tri mix back then.