Moving the Engine & ZF Forward

Put a fat friend in the passenger seat.

quote:

Originally posted by PanteraDoug:
Put a fat friend in the passenger seat.

When will YOU be in town?! ...Mark

That's presumptuous isn't it?

What is the weight distribution on a stock Pantera?

45/55????

The same as a 427 Cobra 40/60.

Racers would normally use ballast to balance the car to their liking.

The problem with loading the nose of the Pantera nose more is that there is only one size spindle.

It's actually very close in size to the original Mustang. I think there was some modelling from that car used.

Eventually the front spindle in the Mustang needed to be increase by the 70 model year.

How would a person ( I'm not smart enough) figure the weight distribution change by saving 200lbs in engine weight by using a aluminum engine block,cylinder heads, intake manifold? based on the current weight distribution being 40/60 as per Doug's ratio...Mark

I wondered the same thing today, but it was just an afterthought, because I was looking at getting an aluminum block for my new engine!

quote:

Originally posted by PanteraDoug:
Put a fat friend in the passenger seat.

I did that once and the problem was that the car didn't want to stop very well with the extra 250 pounds in the passenger seat. That really wasn't fun at close to 120 mph going into turn #3 at the Inde Motorsports Ranch.

Borrow a set of corner weights, or find a high-end alignment shop that has corner weights. I'm sure they wouldn't charge much to tell you what your weight distribution is at each corner. Heck, they'd tell you that for free if you paid them to corner weight and align your car.

Anyone on this board have their car corner weighted? Do you know the weight at each corner?

Jack...? Jack...? ...Jack? (think droll monotone teacher saying "Bueller?... Bueller?") This seems like just the kind of information you'd know, and something you've probably done to your car.

DeTomaso said Pantera wt distribution was 42%/58% frt/rear but it depends somewhat on whether you're speaking of a pre-L, an L model or a wide-body. A stone-stock pre-L was supposed to be 2932 lbs. My 'L' as driven with a 1/2 tank of gas was 3350 lbs before I started modding it. Never weighed a GT-5 or -5S. A Mangusta is 40:60.

With 30 years of modifications, our street-legal 'L' is now down to 2690 lbs as- driven with 1/2 tank of fuel; the as-modified wt balance is 43.5%/56.5% frt to rear. It will come down a bit more in back if I ever get my Fontana aluminum block finished. All-mechanical race scales are only about $250 a set if you decide to seriously start playing this game. You'll also need a set of adjustable spring-height shocks.
Our corner weights
680 lbs frt per corner stock
982 lbs per rear corner stock

590 lbs frt per corner modded
755 lbs rear per corner modded

quote:

Originally posted by Bosswrench:
DeTomaso said Pantera wt distribution was 42%/58% frt/rear but it depends somewhat on whether you're speaking of a pre-L, an L model or a wide-body. A stone-stock pre-L was supposed to be 2932 lbs. My 'L' as driven with a 1/2 tank of gas was 3350 lbs before I started modding it. Never weighed a GT-5 or -5S. A Mangusta is 40:60.

With 30 years of modifications, our street-legal 'L' is now down to 2690 lbs as- driven with 1/2 tank of fuel; the as-modified wt balance is 43.5%/56.5% frt to rear. It will come down a bit more in back if I ever get my Fontana aluminum block finished. All-mechanical race scales are only about $250 a set if you decide to seriously start playing this game. You'll also need a set of adjustable spring-height shocks.
Our corner weights
680 lbs frt per corner stock
982 lbs per rear corner stock

590 lbs frt per corner modded
755 lbs rear per corner modded

Hello "Boss"; Very Much Appreciate your "Real World Numbers"!

Based on your factual corner weights, there is NO WAY a stock DeTomaso Pantera had a 42%/58% Front to Rear weigh distribution!!!

Your weigh modifications REMOVED 604 lbs from the front & 330 lbs from the rear, yet ONLY changed the weight distribution percentile 1.5% in the front from the rear from the "CLAIMED" factory weight distribution???!!!

Was Alejandro standing on the front of the Pantera when the car was weighed at the factory??!!

Your weight modifications removed TWICE(604lbs)as much weight from the front than from the rear(302lbs) for a relatively insignificant weight distribution ratio change of 1.5%!!??

Based on those ratios & subsequent weight distribution changes, that BIG $$$$ Fontana aluminum block is going to change the weight distribution the equivalent of a couple of Cuban cigar stubs in the ash tray ...Mark

quote:

Originally posted by Bosswrench:
DeTomaso said Pantera wt distribution was 42%/58% frt/rear but it depends somewhat on whether you're speaking of a pre-L, an L model or a wide-body. A stone-stock pre-L was supposed to be 2932 lbs. My 'L' as driven with a 1/2 tank of gas was 3350 lbs before I started modding it. Never weighed a GT-5 or -5S. A Mangusta is 40:60.

With 30 years of modifications, our street-legal 'L' is now down to 2690 lbs as- driven with 1/2 tank of fuel; the as-modified wt balance is 43.5%/56.5% frt to rear. It will come down a bit more in back if I ever get my Fontana aluminum block finished. All-mechanical race scales are only about $250 a set if you decide to seriously start playing this game. You'll also need a set of adjustable spring-height shocks.
Our corner weights
680 lbs frt per corner stock
982 lbs per rear corner stock

590 lbs frt per corner modded
755 lbs rear per corner modded

You are using an aluminum radiator, carbon fiber front and rear lid... and this is with a driver and passenger?

Your left and right loading are exactly equal?

More times than not, the professional drivers are the size of jockeys?

If this is more than a mental exercise, if a reader out there is seeking better "grip" in corners, dial-in about 5 or 6 degrees of positive front caster, replace the rubber or poly suspension bushings with heim joints (spherical rod ends) and stiffen up the chassis where the upper rear control arms attach. Install good shocks, stiffer springs and the Euro-sized rear anti-sway bar. Set the ride height properly, dial-in the 4 corner weighting, and dial in the suspension settings (toe & camber). These are things that should be done before something as radical as moving the engine is performed.

Back to the mental exercise ... I do not believe the Pantera's "approximately" 40/60 weight distribution is ideal, but I would also point out there is no proof that 50/50 weight distribution is ideal. I think 50/50 is a goal for people who are working with front engine cars where the weight distribution tends to be 60/40. There are a lot of racing cars having a rearward weight bias. I'm thinking of F1 & Rally Racing. In general I believe the most important goal is to put all the weight between the axles, as close to the middle of the car as you can squeeze it together, for a low polar moment of inertia. In that regard the Pantera is already in good shape.

The distance the weight is moved plays very strongly into the effectiveness of the move in altering the weight distribution. Moving the engine & trans a few inches forward will not make a big difference at all. They are already in the middle of the car. Moving the A/C condenser forward would possibly be more helpful, because although it doesn't weigh much the weight is being moved a significantly greater distance. Relocating the fuel tank to the front is generally what Pantera racers do, to put some weight on the nose. This also moves that weight a significant distance forward.

If you want to move the engine & trans don't move them forward, move them downward. Lower the CG. Install a "flipped" ZF, a small diameter flywheel, a small diameter multi-plate clutch and a dry sump lubrication system. Then drop the engine/trans assembly several inches.

Here are my numbers with the 4.6L '99 Cobra engine. When I started the project Wilkinson said it would shave about 175 lbs of the weight. The car #1549 was basically stock but had an alu manifold, Hall headers and a Holly. It weighed 3090 (measured on a truck scale) w 1/2 tank of gas. A lot of other things were done besides the engine some of which probably added weight.

The cars sure must have been heavier than they said they were. After all, back in the 70-80's car scales were not as readily available as they are now...

I weighed my PB in at 1376Kg (3033Lbs), with 3/4 filled fuel tank, but this was without trunk insert, no spare wheel, and the really heavy iron inlet manifold changed for an alloy Edelbrock one, and some other little changes. Weight distribution then was 42,3/57,7%

In its current condition it should be with as much fuel, down to 1330Kg (2932Lbs). Need to weigh the car back once on its wheels again.

I have a set of Intercomp car scales for the fun of weighing

It's my understanding the Gp4 factory race cars were about 2,700 pounds.

This actually puts them in the "vicinity" of the GT40 MkII's and 427 Cobras.

To me this is interesting because doing a test drive on a 427 Cobra s/c and a Gp4 Pantera in the same day ON THE STREET, no stop watches or timing devices going (this was way before digital) I was actually leaning to the Pantera as being faster?

It was an iron head car too, not the fancy aluminum race heads that appeared in the '80s from Ford.

I don't have my notes in front of me but the A3 heads save about 100 pounds over the iron heads.

I think that brings the engine weight down to just about 400#'s?

In my case though, I'm quite sure the Weber setup puts a few pounds back on vs. the single Holley?

A carbon fibered car probably would save 100#'s over the Gp4 aluminum skin configuration?

I had a portable truck scale that I used to tune the suspension balance with. Sold that. I'll go find another one. I'm not a jockey but I don't wear a helmet and I drive naked, so that helps.

Did you know it isn't against the law to drive naked? The people in the tour buses take lots of pictures, wave and yell things in foreign languages. It all sounds like Swedish to me?

I think they just want me to take the anti-sub belt off?

quote:

Originally posted by PanteraDoug:

I think they just want me to take the anti-sub belt off?

Now there's a mental image I didn't need this morning...

www.youtube.com/watch?v=ZLE60Aspsu4

quote:

Hello "Boss"; Very Much Appreciate your "Real World Numbers"!

Based on your factual corner weights, there is NO WAY a stock DeTomaso Pantera had a 42%/58% Front to Rear weigh distribution!!!

Your weigh modifications REMOVED 604 lbs from the front & 330 lbs from the rear, yet ONLY changed the weight distribution percentile 1.5% in the front from the rear from the "CLAIMED" factory weight distribution???!!!

Was Alejandro standing on the front of the Pantera when the car was weighed at the factory??!!

Your weight modifications removed TWICE(604lbs)as much weight from the front than from the rear(302lbs) for a relatively insignificant weight distribution ratio change of 1.5%!!??

Based on those ratios & subsequent weight distribution changes, that BIG $$$$ Fontana aluminum block is going to change the weight distribution the equivalent of a couple of Cuban cigar stubs in the ash tray ...Mark

Mark,

Please explain your math? From Bosses numbers, I get 41/59 weight distribution (rounded). I also get a total weight removed of 634lbs. 180 from the front and 454 from the rear for a new weight distribution of 44/56...

Scott

The worst thing I saw was guys weighing a vehicle *without* disconnecting the sway bar then adding corner weights. The sway bar adjustment is as important to the whole thing as the corner weights. If you weigh it without starting with it disconnected you have an arbitrary number.

quote:

Originally posted by ZR1 Pantera:

quote:

Hello "Boss"; Very Much Appreciate your "Real World Numbers"!

Based on your factual corner weights, there is NO WAY a stock DeTomaso Pantera had a 42%/58% Front to Rear weigh distribution!!!

Your weigh modifications REMOVED 604 lbs from the front & 330 lbs from the rear, yet ONLY changed the weight distribution percentile 1.5% in the front from the rear from the "CLAIMED" factory weight distribution???!!!

Was Alejandro standing on the front of the Pantera when the car was weighed at the factory??!!

Your weight modifications removed TWICE(604lbs)as much weight from the front than from the rear(302lbs) for a relatively insignificant weight distribution ratio change of 1.5%!!??

Based on those ratios & subsequent weight distribution changes, that BIG $$$$ Fontana aluminum block is going to change the weight distribution the equivalent of a couple of Cuban cigar stubs in the ash tray ...Mark

Mark,

Please explain your math? From Bosses numbers, I get 41/59 weight distribution (rounded). I also get a total weight removed of 634lbs. 180 from the front and 454 from the rear for a new weight distribution of 44/56...

Scott

Hello Scott; Always willing to explain & ALWAYS willing to be corrected!

Here is Bosses post & numbers...

"DeTomaso said Pantera wt distribution was 42%/58% frt/rear but it depends somewhat on whether you're speaking of a pre-L, an L model or a wide-body. A stone-stock pre-L was supposed to be 2932 lbs. My 'L' as driven with a 1/2 tank of gas was 3350 lbs before I started modding it. Never weighed a GT-5 or -5S. A Mangusta is 40:60.

With 30 years of modifications, our street-legal 'L' is now down to 2690 lbs as- driven with 1/2 tank of fuel; the as-modified wt balance is 43.5%/56.5% frt to rear. It will come down a bit more in back if I ever get my Fontana aluminum block finished. All-mechanical race scales are only about $250 a set if you decide to seriously start playing this game. You'll also need a set of adjustable spring-height shocks.
Our corner weights
680 lbs frt per corner stock
982 lbs per rear corner stock

590 lbs frt per corner modded
755 lbs rear per corner modded

"If", I am interpreting Bosses numbers correctly, the frontend mods removed a total of 180lbs.

The rearend mods removed a total of 454lbs.

WOW!!!...My initial numbers are Waaaaaaaaaaay OFF!!!

I BLAME Obama!!!

Thanks Scott for the correction! ...Would you like me to do your taxes for you?! ...Mark

quote:

Would you like me to do your taxes for you?! ...Mark

Depends on who's math you are going to use!!!

LOL

There's a little more to it than the numbers I posted. I've chosen to ADD weight in several areas for handling, comfort & performance/insurance.
My front 245-50 x15" tires on 8" Campys are each 4 lbs heavier than the 225-50s on 7" Campys I used before. The rear 295-50 x15s on 10" Campys are each 8 lbs heavier than the old 275-55x 15s on 8" Campys.
The Aviaid 10-qt oil pan is 4 lbs heavier than the OEM Boss-351 pan that came on the car.
The Revson front spoiler is 4 lbs and my poly splitter is another 3 lbs so that's all added weight on the nose. There's a few more piddly little things added as well.
So there's a LOT more aluminum, mag & even titanium, and a corresponding drop in iron content in the car today. Not much left to lighten up of any significance except aluminum rear uprights that I need to make as I simply can't afford the $3000 cost of bolt-ons.

quote:

except aluminum rear uprights that I need to make as I simply can't afford the $3000 cost of bolt-ons.

You have to admit that they are really pretty to look at though?

...do the aluminum billet control arms wind up lighter or heavier than the original stock units?