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Gearhead_42

VPI Numbers you just can't get your head around

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We all have that one car you just can't believe is so few points... or so many, for that matter.  So what needs to be looked at in the new VPI tables?  And back it up, not just "he's faster, so I should get more points", but show the numbers as to why ...

 

Here's mine:

 

S13 Nissan 240SX: 350 points. 2 door coupe, 15" wheels stock, 155 horsepower, 2583 lbs, 15.8 gallons of fuel, 4 wheel independent suspension, no oil cooler stock.  Lots of aftermarket support.  Theoretical 202 horsepower engine swap: 435 points new total.

 

Second Gen Rx7:  275 points.   2 door coupe, 15" wheels stock, 148hp, 2560 lbs (official) 16.6 gallons of fuel, 4 wheel independent suspension, big oil cooler stock.  Lots of aftermarket support.  Theoretical 202 horse engine swap: 368 points new total.

 

I chose my car, but I chose it before VPI existed, so enquiring minds want to know :lol:  Second gen guys, strip all the weight out of both cars, are you telling me yours is 75 points slower?

Edited by Gearhead_42
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That weight number for 2nd gen is minus 10%.

 

I have no idea why the 2nd gen got lowered.

 

We have coilovdrs, aero, an engine swap, bushings + some other stuff and still have points to play with.

 

Why theoretical 202 horse engine?  That would require full porting, new duel injectors, header, intake and others to get to.

 

Our old engine with everything thrown at it made 146 rwhp...  another 50 hp would have been tough!!!

 

Also, the aftermarket has forgeeten about 2nd gen rx7s.  They are hard to get food non drifty road race parts for.  I would argue the 240 has the same or better parts available for road racing.

Edited by wvumtnbkr

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Recent results would suggest the second gen RX7 is a comfortably competitive platform right now.  GMS and Sahlens have been doing quite nicely with them.

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@wvumtnbkr Yeah, not trying to pull you guys down, just wondering at the lack of parity given such close numbers. I used the Chumpcar tabulated weights for both cars, and the 202 number was just what I ised for my swap math. Could have used 185 or whatever, the gap is maintained...

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16 minutes ago, Gearhead_42 said:

@wvumtnbkr Yeah, not trying to pull you guys down, just wondering at the lack of parity given such close numbers. I used the Chumpcar tabulated weights for both cars, and the 202 number was just what I ised for my swap math. Could have used 185 or whatever, the gap is maintained...

I think you have a point, but I also think that the difference between 275 and 350 points is pretty small potatoes. If it were 500 vs. 575, that is a big deal.

 

The RX-7 is a theoretically difficult car to put a value on because of the stock engine. This gas guzzling, torqueless, probably overrated at 148 hp rotary is "eh, could be pretty good" at 275 points, but if you swap it for a conventional engine it is suddenly "wow, this is a great car at 275 + _____ points".

 

Put your information into a formal document for VPI change request and send to Phil... I'm sure there are a ton of cases like this where the points are "pretty reasonable" but could be changed a little.

Edited by enginerd
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Not all values are fresh.  There are A LOT of cars on the table and I do not have the time or sanity to review all at once.  If a value seems perplexing to someone, they should email it to us for review.

 

That being said, a few cars have artificially low values on purpose.  We are trying to encourage their use.  The most common example is the Camaro and Mustang.

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Swap a k24 and trans into a second gen rx7.  Prep both cars with similar components.  Have a few skilled drivers run hot laps.  Be data geeks and figure out if the point delta makes sense on regards to chassis.

 

 

I'll drive 😁

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54 minutes ago, Hi_Im_Will said:

Recent results would suggest the second gen RX7 is a comfortably competitive platform right now.  GMS and Sahlens have been doing quite nicely with them.

Thanks!

 

Sahlens with every rotary trick and $ecu.  Us with Chevy minivan engines.

 

Surprisingly, they pull us on the straights....

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3 hours ago, Gearhead_42 said:

We all have that one car you just can't believe is so few points... or so many, for that matter.  So what needs to be looked at in the new VPI tables?  And back it up, not just "he's faster, so I should get more points", but show the numbers as to why ...

How about pictures?

150 points:

255px-1st-Toyota-MR2.jpg

 

Or 150 points:

18s14vshle521jpg.jpg

 

I couldn't find any reviews that actually tested a Chevette on a track ... but I did find an article that claimed it made 23 whp with the automatic. :lol:

 

Best quote:

"As far as speed, you have to pick your battles. If your Chevette is an automatic, don’t pick any."

Edited by mender
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2 hours ago, wvumtnbkr said:

Thanks!

 

Sahlens with every rotary trick and $ecu.  Us with Chevy minivan engines.

 

Surprisingly, they pull us on the straights....

I talked with them about wind tunnel testing recently. No expense spared. Fresh tires every couple hours is nice if you can afford it as well.

I guess WRL instituted a rule that only allows 5 total tires and one impact wrench over the wall at a time. They are trying to curb some spending. At Mid-Ohio the Sahlens cars would drive to the garage change tires then return to pit lane to fuel.

We pitted and garaged next to them last weekend. They were super nice guys and if you have the money you might as well spend it.

Edited by Kentite

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Looking at some lap times for Sahlen’s. The picked up about 2.5 seconds from 2016 to 2017 at PIRC. Same drivers, same cars that I though were maxed out already. 

Is that a reasonable jump for “pro” team? We picked up 3 seconds,  but our car and driver’s saw much improvement over the last year.

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Sahlens did a 2:03 in 2015 with Charcoal. 

 

Troy did a 2:00 flat in 2015.

 

We went from a 2:10 in 2015 to a 2:04 in 2017 (swapped).

 

RBank and CYR did 2:09s.

 

The race winner did a fast lap of 2:03....  The dreaded 400sx.

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38 minutes ago, Kentite said:

Looking at some lap times for Sahlen’s. The picked up about 2.5 seconds from 2016 to 2017 at PIRC. Same drivers, same cars that I though were maxed out already. 

Is that a reasonable jump for “pro” team? We picked up 3 seconds,  but our car and driver’s saw much improvement over the last year.

 

Improved pavement?  Dunno, just guessing here.  My 240SX was good for a 2:10 and a 2:11 this year with two of my talented amateur drivers... the rest were around the 2:13-2:14 mark. Might have been able to improve in second stints if we'd made it that far :lol:

Edited by Gearhead_42

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Out of curiosity, why did the 2nd generation MR2 value go down?

 

These 2 Toyota vehicles now have the same value. I don't know Toyota's well, so I might be missing something obvious. 

 

280px-Toyota_MR2_(SW20)_ca_1995_at_Snett

 

and

 

220px-'81_Toyota_Tercel_Coupe.jpg



 

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15 minutes ago, wvumtnbkr said:

Sahlens did a 2:03 in 2015 with Charcoal. 

 

Troy did a 2:00 flat in 2015.

 

We went from a 2:10 in 2015 to a 2:04 in 2017 (swapped).

 

RBank and CYR did 2:09s.

 

The race winner did a fast lap of 2:03....  The dreaded 400sx.

Didn’t realize they were that fast in 2015. Amazing how many cars have eclipsed the time of the much hated 400sx at PIRC the last two races there.

Since you know a thing or two about second gen RX7’s how much power can one expect out of the stock engine? Never owned a rotary, but I’m always tempted by them.

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7 minutes ago, Kentite said:

Didn’t realize they were that fast in 2015. Amazing how many cars have eclipsed the time of the much hated 400sx at PIRC the last two races there.

Since you know a thing or two about second gen RX7’s how much power can one expect out of the stock engine? Never owned a rotary, but I’m always tempted by them.

Stock engine?  Do you mean stock ports, stock intakes?  I think 175 is tough but doable.

 

start porting, and the question becomes how often do you want to rebuild it?  How long will the trans last?  How much fuel do you wanna use?

 

Ours (with stock ports, stock intake manifolds) had a header, all accessories removed, some fuel pressure tuning, some MAP trickeration and a decent cold air intake put down a whopping 146 RWHP.

 

In order to make much more than that, either MORE fuel pressure or more injector would be needed.  These are both unrestricted now.  ECUs are unrestricted.  Porting is not restricted.  200 should be fairly easy with those restrictions removed.

 

I just like torque!  I also like spending $200 for an engine that every junkyard has 42 of them in stock.  Instead of $600.00 in seals just to revive a tired engine.

 

 

To clarify, I am NOT saying Sahlens is doing anything wrong.  Hell, they probably have legal room to make more HP.  It just costs money and time to make that HP.

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Other cars that make you go "Hmmm".  Our 1994 Volvo 940 has a base value of 450 points.  Stock turbo add 100, so we're 550 without doing anything else.  I sent a letter to Phil, but we're way behind getting into a non-EC class at this point that it doesn't matter. 

 

Whereas my autocross car, 2003 Nissan 350z is 570 points.  After we blew the Volvo motor at Pitt, I suggested we just build the 350z.  Probably won't happen though.

 

I ran 2:10's at Pitt in 2015 and 2:04 this year, but we've done a number of car improvements in that time.

Edited by CoachMK21
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3 minutes ago, Snorman said:

Correct me if I'm wrong, but isn't fuel consumption a huge issue with the rotaries? 

S. 

Can be.  With 146 RWHP we were using about 7 to 7.5 GPH.  Stock tank is 16.5.

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11 minutes ago, wvumtnbkr said:

Stock engine?  Do you mean stock ports, stock intakes?  I think 175 is tough but doable.

 

start porting, and the question becomes how often do you want to rebuild it?  How long will the trans last?  How much fuel do you wanna use?

 

Ours (with stock ports, stock intake manifolds) had a header, all accessories removed, some fuel pressure tuning, some MAP trickeration and a decent cold air intake put down a whopping 146 RWHP.

 

In order to make much more than that, either MORE fuel pressure or more injector would be needed.  These are both unrestricted now.  ECUs are unrestricted.  Porting is not restricted.  200 should be fairly easy with those restrictions removed.

 

I just like torque!  I also like spending $200 for an engine that every junkyard has 42 of them in stock.  Instead of $600.00 in seals just to revive a tired engine.

 

 

To clarify, I am NOT saying Sahlens is doing anything wrong.  Hell, they probably have legal room to make more HP.  It just costs money and time to make that HP.

I talked to them at length on Friday and don’t think they are doing anything wrong either. We talked about how much time they spend building the cars the limit of the rules. Which I guess with an entire garage of specialists and relatively unlimited budget isn’t an insurmountable task.

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