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-   -   How to plan for an efficient driveline. (https://www.lateral-g.net/forums/showthread.php?t=10515)

drphibes 07-31-2007 12:03 PM

How to plan for an efficient driveline.
 
I plan on putting a Shafiroff 598 BBC that will be pushing 875 at the crank in a '69 Camaro. I want to be able to put as much of that to the rear wheels as possible. I am doing my research on driveline components that will yield the most efficient driveline.

What suggestions do you have? Transmission? Driveshaft? Other Components etc. Thanks

Robert

Steve Chryssos 07-31-2007 01:05 PM

That's a lot of beans. :hail: Manual or Auto? What will you use for rear tires? Will you also run slicks in addition to street tires? What is target vehicle weight? What are your intended uses for the car? Assign percentages for the car's life at the track vs street? What are cam specs? Carb or EFI? What is the altitude where you live (very important on carbureted monster big blocks.)

This is a tough topic. Monster big blocks are in a class by themselves. They make crazy torque just off idle and then hold that number thru redline until they run out of air. This subject always generates a lot of differing opinions. But very few people have any actual experience with motors bigger than about 509-540. Even fewer have experience with big inch motors built for the street. During your research, be sure to weigh all thread responses against actual personal experience--not: "I saw a guy on some message board who made a pass in the 8's with a junkyard TH350 transmission that was accidentally filled with sand. It was a blown V6, not a 598, but his cousin's sister SWEARS it makes 900HP. Here's a link to the video of that one pass...." :rofl:

My personal project experience includes the following:
Blown and NA carbed 632
NA carbed 638
NA EFI 705

Here we go.

Bowtieracing 08-01-2007 11:25 PM

This is intresting.. 8s with trans full of sand:lol:

Okay but seriously,is there really difference between 9" or 12bolt rears?

I have heard at 9" takes more power to run?

tyoneal 08-02-2007 01:21 AM

Be careful with a hot big inch big block.

As Steve said, They make Crazy Torque!

Heed his words, you might be getting into Too Much of a Good Thing. No Kidding!

Save your money (And your life) and start with something a bit more reserved. (454 HO or something like that) Learn to drive it, enjoy it, then sell it and buy the Engine you mentioned. If you still want it.

I had a BBC that made 650 hp. I thought biggest is best. It wasn't worth a crap on the street, because unless you did nothing more than concentrate on what you were doing, it was way too easy for things to get way out of control. Forget altogether Driving in the rain.

Maybe Shafiroff could build you something about half that power to start with, then upgrade it as you get comfortable with it.

Good Luck!

Ty

Silver69Camaro 08-02-2007 07:59 AM

Quote:

Originally Posted by tyoneal
I had a BBC that made 650 hp. I thought biggest is best. It wasn't worth a crap on the street, because unless you did nothing more than concentrate on what you were doing, it was way too easy for things to get way out of control. Forget altogether Driving in the rain.

You know, that's a good point. My last motor was a 412" small block with all the goodies..ran mid 11's with a crappy 60-ft (high 1.8's). Now I have a bone-stock LS1 motor...and I like the drivability much better. The 412" motor was fun in some ways, but it was WAY to easy to lose control of the car. Now, I can put my foot in it pretty hard, still go fast, and maintain some control. Less tire smoke, more foward motion.

I'll admit it's not as fun for car shows when people ask "What'll do in the 1/4?", but who cares...it's all about driving the thing.

QSPres 08-02-2007 10:18 AM

If you're not going to put sticky tires on it, a 8.5" 10 bolt, TH350 and steel driveshaft will be fine... Spend all the money on the rebuilds though, you'll need it.

If you're going to drag it, I'd probably only change the trans to a TH400.

Steve Chryssos 08-02-2007 11:10 AM

Good artice for determining wheel torque. Put yer thinkin cap on before reading.

http://www.mustangsandmore.com/ubb/D...orqueVsHP.html

customcam 08-03-2007 01:29 AM

Steve can u translate that page for us :D

Steve Chryssos 08-03-2007 03:10 PM

The bottom line is that your complete engine/drivetrain combination boils down to "Wheel Torque" And wheel torque can be determined mathematically thru the following:
-Engine Power Band
-Coupling Device (converter or clutch) Multiplication Factor where applicable.
-Transmission Gear Ratios
-Rear End Gear Ratio
-and Tire Diameter.

For example, double overdrive is of little use if it takes your engine out of its power band. Gearing your engine to take advantage of double overdrive might render 1st gear useless. A drag car is usually more concerned with taking advantage of 1st gear, while a touring car is more concerned with making the most of overdrive.

We cannot and should not take this conversation further without first getting answers to the basic questions:

Quote:

Manual or Auto? What will you use for rear tires? Will you also run slicks in addition to street tires? What is target vehicle weight? What are your intended uses for the car? Assign percentages for the car's life at the track vs street? What are cam specs? Carb or EFI? What is the altitude where you live (very important on carbureted monster big blocks.)

drphibes 08-03-2007 04:08 PM

Thanks for the replies. Steve you are going to make sure I get an answer! Thanks :thumbsup:

Proposed specs:

Transmission: Auto
Target Vehicle Weight: 3400# max
Vehicle Usage: 90% Street 10% Track - Both drag and road.
Induction: Carb
Altitude: Sea Level
Rear End Gears: 3.72
Tires: Rear 345/30R18 Michelin Pilot Sports PS2 Street, Comparable size slick for track.
Engine Power Band: 4000 -5500 Max TQ at 4800

Probably TH400 trans, but don't know what gearing would be right now. That's what I am trying to decide. Which transmission, what gearing options I would have for it.

Thanks again.:bow:

Robert


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