18 replies to this topic

[dgs]

Did the drivers of the March 83C, 84C, 85C, etc & Lola T800, T900, etc, Indycars, use  different chassis on road circuits compared to oval circuits ?

 

For instance did they have different wheelbases ?

 

 

[B Squared]

I quickly looked at my CART rulebooks from this timeframe and all I see is minimum and maximum dimensions diagramed in the pages. I don't recall different chassis' for select races other than when Penske and Truesports were using stock-block engines for certain road courses and back to the turbo Cosworths for most of the races. But, again, I don't remember radically different dimensions for the different disciplines. I'll look more in depth at the rulebooks when time allows in the next few days to see if this is correct.

[Henri Greuter]

I quickly looked at my CART rulebooks from this timeframe and all I see is minimum and maximum dimensions diagramed in the pages. I don't recall different chassis' for select races other than when Penske and Truesports were using stock-block engines for certain road courses and back to the turbo Cosworths for most of the races. But, again, I don't remember radically different dimensions for the different disciplines. I'll look more in depth at the rulebooks when time allows in the next few days to see if this is correct.

 

I recall something about that the Lola T9100 (1991 car) initially was designed that at Indy it used an asymmetric suspenison setup to have a little left side weight bias. But eventually that was forbidden so it never happened.

 

In general there was a bit of difference in primarily bodywork parts and of course the wings. I know that the 1994 Penske required other rear center fusilage bodywork because of the higher engine. That car also used a slightly lower rollhoop than elsewhere, also in an attempt to reduce resistance a bit. Penske may have done that with other cars too but I am not aware of it. But knowing what I know about team Penske: if it was permitted before and after 94, good chance they did it in other years too.

 

What I always have felt the funniest was with the 1986 March 86C. Initially that car was supposed to run at the Speedway without the `shoespoon` air defectors in front of the rear wheels. They were given a try at Indy after all and all of a sudden every team with 86C's used them! There were at least two different types or turbo lay-out existing for them but I am not sure it one of them was a 1987 development of if both systems were  available in '86 already.

 

Henri

[Bloggsworth]

The Lotus 34 (1964) certainly had different length suspension components left and right to offset the weight to the left, but there was no provision on the monocoque for different wheelbases - I suppose, had Lotus wanted to, they could have canted the suspension components forward and/or backward.

[Sisyphus]

The 1963 Lotus 29 also had offset suspension and winning 1965 Lotus 38 plus many of the other rear engine Indy cars of the period. 

 

But I believe the offset suspension was in use on the Roadsters before Lotus came--please correct me if I'm wrong.  It tends to be a little more obvious on the narrow bodied Lotus.

 

At some point, I presume offset suspension was out lawed but I don't know when or why that was.

[B Squared]

I would think that the only way to change the wheelbase on the cars dgs mentioned would be different lengths of the casting that transitions from the back of the engine to the front of the gearbox and I can't recall seeing different lengths to choose from with this casting for the same marque in the same model year.

[Obster]

I seem to recall from the On Track/NSSN days-pre internet-that the early Marches had both oval and roadcourse sidepods. Also, that some teams-Teddy Mayer's(?) -found that the roadcourse pods worked better on the ovals than the oval pods did-something like that.

Many years ago, guys!

[PeterElleray]

Brian,

 

You would typically do it with the sweep of the front wishbones to move the front wheels back or forwards. This was something that became more complicated when CART introduced footbox dimensional regs although off the top of my head i do not think they had a 'drivers feet behind front axle' rule as in Europe.

 

When i worked for Lola in 88/89 there was a speedway kit which provided subtly different left/right side wishbones etc to give a small degree of asymmetry and offset - but very subtle. Also gave positive camber on the left wheels for the ovals and staggered castor .

 

All that in addition to offset corner weighting the car  and different wing angles side to side.

 

Quite a few of those adjustments could be done on the standard parts but the wishbones were definately special - also the wheel hub and bearing package ran different seals left/right.

 

Fascinating stuff to someone brought up on European road racing at the time.

 

Do you have a 1987 or 1988 CART or USAC rule book, could i PM you for a few dimensions i need?

[B Squared]

Thanks for your answer Peter. I looked at my rule books, and I can't believe this, I've got 1981, '83 through '86 and '89 through '91. If I can help in any way, I'll be glad to, but I have no idea why I didn't get 1982, '87 and '88.

[JacnGille]

I seem to recall from the On Track/NSSN days-pre internet-that the early Marches had both oval and roadcourse sidepods. Also, that some teams-Teddy Mayer's(?) -found that the roadcourse pods worked better on the ovals than the oval pods did-something like that.

Many years ago, guys!

I remember something along these lines too.

[Marc Sproule]

the 83cs definitely had droopy sidepods, quite noticeable in pan shots on the ovals.

 

eventually ..'84?...a rule change mandated a static test with a weight being hung on the sidepod to measure deflection.

[PeterElleray]

Thanks for your answer Peter. I looked at my rule books, and I can't believe this, I've got 1981, '83 through '86 and '89 through '91. If I can help in any way, I'll be glad to, but I have no idea why I didn't get 1982, '87 and '88.

Brian - 1989 would be fine, i'll PM you if that's ok?

 

Many Thanks

 

Peter

[B Squared]

Brian - 1989 would be fine, i'll PM you if that's ok?
 
Many Thanks
 
Peter

Absolutely

[PeterElleray]

Brian - PM sent, thanks again.

 

Peter

[D-Type]

Try asking the same question on http://www.trackforu...104-s-Nostalgia there are some on there with encyclopedic knowledge of Indianapolis and Indycar

[PeterElleray]

Good forum.

[dgs]

Were the chassis numbers of March 83C, 84C, 85C & Lola T800, T900 cars recorded at races they competed in ?, 

[Henri Greuter]

I have been told that the CART registers in which chassis numbers on each CART event was kept ended up in the hands of Indycar and were discarded since Indy had been part of another championship as well that was deemed of more historical importance related with the speedway than the CART series. So when room within the building had to be made, the CART stuff went out as trash.....

(this was some 1979 CART/USAC pains still being felt by some......)

 

 

For Indy I have tried to compile a record based on the yearbooks and theinfo I found on internet but it is incomplete and not 100% correct.

 

 

Henri

[Eaglenindy]

Beginning in the 80's with the Marches and Lola's continuing upto and ending about 10 years ago, factories, larger teams and fab shops like Howerton's commonly made alternate suspensions.   It began after the switch from front rocker arms to wishbone or A arms.  Wheelbases and tracks were commonly changed by A arms. 

 

Teams like Penske had optimized  short WB suspensions built for tighter tracks ad long WB's for more flowing circuits.   Same on ovals, but on higher speed tracks like Indy, MIS and Fontana, narrower track widths were made to tuck in the tires and create a smaller hole for the car to punch through the air.

 

Note, this was done with the front suspension to change WB only as the rears could only be  for changed track widths.

 Hope that helps