Class I 944 versus SP1
11-26-2006 | 11:19 PM
#1
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From: Tenafly, NJ
Class I 944 versus SP1
Anyone any idea how these cars would compare with the same driver? I'm having a sp1 car build now and I've seen a class I car lap Brainerd in 2:03 which is pretty amazing for a 150bhp car, or is it. What kind of mods do class I cars typically run?
11-27-2006 | 12:22 AM
#3
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From: Ontario, Canada
I ran an SP1 car at Daytona and did a 2:26.2, while the fastest I class car did a 2:23.1 as shown on the PCA results, track records shows here:
http://www.pca.org/clubrace/track_re...ck-Records.htm
http://www.pca.org/clubrace/track_re...ck-Records.htm
only 12 days to my name so far in a 996.
11-27-2006 | 10:37 AM
#5
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From: Phoenix, Az
Well the big difference between a I car and SP1 car are as follows
Weight: I Stock = 2800 or so without driver , SP1 = 2600 with driver or about 2400-2450 no driver. Save 300+ lbs. This weight savings comes from stripped interior & all non-essential items (A/C, heat etc) - Speed advantage SP1, Cost = even (costs only time to strip a 944 SP1 since no FG or lexan allowed)
Wheels/Tires: I-stock 8 or 9" wide wheels any diameter and tire, SP1=15x7 Cookie cutters or Phone dials with Toyo 225/50 R15. This means any fast I-stock car will have sticker tires and much larger tire bill. ALL SP1 cars will be on the same tire that lasts for 1/2 season competitivly and costs less to buy. Plus with tread they can be used in the rain so no need for seperate rain tires.
Seed advantage I Stock, cost = SP1
Suspension
I-stock allows rear coil over and any shock. This means you can run some really nice fancy racing dampers. Plust you can run spherical bearings. SP1 has strict limits on shocks (off the shelf Koni yellows "Street" shocks at $650 a set only) and limited spring rates. No rear coilovers and non metalic bushings. So the SP1 suspension costs far less to max our 100%, but is not s fast st I-stock.
Speed advantge I-stock, Cost = SP1
Engine.
Both I-stock and SP1 have similar engine rules. SP1 does allow chips, but these are worth 2-3 hp. In the end I figure the hp levels to be quite similar 130-134 rwhp is good for a 944 spec.
Engine = equal.
So overall the I-stock car has a more developed suspension and wheel/tire package. The SP1 car has less overall weight and has a much cheap tires and suspension. On the west coast there are very few I-stock cars and a well driven SP1 car and run with G, H and even some F cars depending on the track.
Weight: I Stock = 2800 or so without driver , SP1 = 2600 with driver or about 2400-2450 no driver. Save 300+ lbs. This weight savings comes from stripped interior & all non-essential items (A/C, heat etc) - Speed advantage SP1, Cost = even (costs only time to strip a 944 SP1 since no FG or lexan allowed)
Wheels/Tires: I-stock 8 or 9" wide wheels any diameter and tire, SP1=15x7 Cookie cutters or Phone dials with Toyo 225/50 R15. This means any fast I-stock car will have sticker tires and much larger tire bill. ALL SP1 cars will be on the same tire that lasts for 1/2 season competitivly and costs less to buy. Plus with tread they can be used in the rain so no need for seperate rain tires.
Seed advantage I Stock, cost = SP1
Suspension
I-stock allows rear coil over and any shock. This means you can run some really nice fancy racing dampers. Plust you can run spherical bearings. SP1 has strict limits on shocks (off the shelf Koni yellows "Street" shocks at $650 a set only) and limited spring rates. No rear coilovers and non metalic bushings. So the SP1 suspension costs far less to max our 100%, but is not s fast st I-stock.
Speed advantge I-stock, Cost = SP1
Engine.
Both I-stock and SP1 have similar engine rules. SP1 does allow chips, but these are worth 2-3 hp. In the end I figure the hp levels to be quite similar 130-134 rwhp is good for a 944 spec.
Engine = equal.
So overall the I-stock car has a more developed suspension and wheel/tire package. The SP1 car has less overall weight and has a much cheap tires and suspension. On the west coast there are very few I-stock cars and a well driven SP1 car and run with G, H and even some F cars depending on the track.
11-27-2006 | 11:35 AM
#7
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From: Phoenix, Az
Originally Posted by bnewport
The 88 944s have more power no? Does SP1 penalize those cars accordingly?
In our experience the hp levels of the 88 motors run 130-134 hp. I had run a 88 motor in my 944 spec car at the same weight and the car was no faster than with the 84 block/87 head motor I run now. All cars run to the same min weight and can use the 88 pistons in any year chassis. The most hp I have seen in a SP1 car is 138 rwhp. My car has 134.2 and fastest car/driver in Az has 135.0. This past weekend I got 2nd place to that car for the 5 straight race, 4 out of 5 times under 1 second at the line. Oh and they last time over the scales we were within 5lbs of each other with driver. I think I need to work on my driving at little more.
FWIW you can shave the head to reach 10.5 max compression ratio. I do not advise it however as fresh stock build head will make solid hp.
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11-27-2006 | 07:10 PM
#8
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From: Tenafly, NJ
Have you seen much variance in lap times versus time of year? I talked with a local class I guy and he's seen variances between 1:58 and 2:03 depending on the time of the year. Maybe in AZ, it's more constant.
11-27-2006 | 08:10 PM
#9
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From: Phoenix, Az
Originally Posted by bnewport
Have you seen much variance in lap times versus time of year? I talked with a local class I guy and he's seen variances between 1:58 and 2:03 depending on the time of the year. Maybe in AZ, it's more constant.
not 5 seconds, but definitely a variance. We even see it from the am to afternoon run sessions.
11-27-2006 | 09:49 PM
#10
Three Wheelin'
Joined: Dec 2001
Posts: 1,561
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From: Hailey, Idaho
It is absoutly amazing how fast the I class PCA cars have gotten since I left PCA the last time. . I know an I car can run 8"and 9"s but the SP1's have almost a 400 pound advantage. I ran at Putnam in SP2, and figured that I would blow the I's away. WRONG!!!!
I did only run 3 sessions due to getting sent home with a shiny new 13/13, but I doubt that I would have equaled the I's times, even if I had made the weekend. The main thing is that comparing different cars with different drivers is like comparing apples to oranges.
2:23's at Daytona with an I car is incredible, because the ITS SCCA Mazda RX7's just barely go below 2:20. It had to have an incredable driver, or nitrous. One thing about Daytona, horsepower rules, above all. I'm sure not calling the guy a cheater, I didn't even look up who it was.
Bill Seifert
1987 944S Race Car
I did only run 3 sessions due to getting sent home with a shiny new 13/13, but I doubt that I would have equaled the I's times, even if I had made the weekend. The main thing is that comparing different cars with different drivers is like comparing apples to oranges.
2:23's at Daytona with an I car is incredible, because the ITS SCCA Mazda RX7's just barely go below 2:20. It had to have an incredable driver, or nitrous. One thing about Daytona, horsepower rules, above all. I'm sure not calling the guy a cheater, I didn't even look up who it was.
Bill Seifert
1987 944S Race Car
11-27-2006 | 10:22 PM
#11
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From: Ontario, Canada
2:23's at Daytona with an I car is incredible, because the ITS SCCA Mazda RX7's just barely go below 2:20. It had to have an incredible driver, or nitrous. One thing about Daytona, horsepower rules, above all. I'm sure not calling the guy a cheater, I didn't even look up who it was.
Bill Seifert
1987 944S Race Car[/QUOTE]
No name calling here either, but that car blew by me in my SP1 car on the banking. It intrigued me that it had a stock car like rear air dam that must have been six inches high and was vertical. I can't imagine the drag that must induce.
Having said that he was a good driver with a well sorted car, including $$$$Moton's$$$$. I will be at Sebring in February for the PCA race and we'll see how the cars and drivers stack up there.
Bill
Bill Seifert
1987 944S Race Car[/QUOTE]
No name calling here either, but that car blew by me in my SP1 car on the banking. It intrigued me that it had a stock car like rear air dam that must have been six inches high and was vertical. I can't imagine the drag that must induce.
Having said that he was a good driver with a well sorted car, including $$$$Moton's$$$$. I will be at Sebring in February for the PCA race and we'll see how the cars and drivers stack up there.
Bill
11-28-2006 | 05:59 PM
#12
Three Wheelin'
Joined: Dec 2001
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From: Hailey, Idaho
comatb
Lord, that must be a heck of a tow for you, and to do it twice in 4 months. I know when I went to Mosport, it was a long way,(Don't remember how long.) and I live 700 miles from Daytona, so it's gotta be 1,500 miles for you. My car won't be together by Feb, but I am planning on Barber in March. It's really a neat track. My biggest problem now, is that a gutted 944S really has no class in PCA. It would either be a SP3 car or GT4 R or S, any one of which I'll get blown away.
By the way, about that class I car, I thought that class I cars had to run the stock rear spoiler. Also, do you have the .83 fifth gear in your car? If you don't, get one, because any track where you need 5th gear, is better with the .83. My N/A 944 went from 122 mph on the banking at Daytona, to 143mph just by going from a .73 5th to a .83. Wacked 6 seconds off my lap time. The itty bitty N/A motor will not push a 944 through the air with the .73 5th gear. It just kinda quits pulling at about 120 or so mph.
Bill
Lord, that must be a heck of a tow for you, and to do it twice in 4 months. I know when I went to Mosport, it was a long way,(Don't remember how long.) and I live 700 miles from Daytona, so it's gotta be 1,500 miles for you. My car won't be together by Feb, but I am planning on Barber in March. It's really a neat track. My biggest problem now, is that a gutted 944S really has no class in PCA. It would either be a SP3 car or GT4 R or S, any one of which I'll get blown away.
By the way, about that class I car, I thought that class I cars had to run the stock rear spoiler. Also, do you have the .83 fifth gear in your car? If you don't, get one, because any track where you need 5th gear, is better with the .83. My N/A 944 went from 122 mph on the banking at Daytona, to 143mph just by going from a .73 5th to a .83. Wacked 6 seconds off my lap time. The itty bitty N/A motor will not push a 944 through the air with the .73 5th gear. It just kinda quits pulling at about 120 or so mph.
Bill
11-28-2006 | 11:33 PM
#14
Drifting
Joined: Jun 2001
Posts: 2,084
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From: new york
Agree with Bill. A PCA I stock class car could not run a tall rear spoiler (however, it can be 6 inches taller than max stock height). I guess motons in front would be okay. But, no coilovers in the rear for torsion bar cars - an exception being those vehicles that came with rear "helper springs", e.g., 968 M030 suspension.
Other than superior driving skill, (which, to be sure, can account for a lot), not sure that I understand how an "I" stock car with pretty much a full interior, no chip and stock gear ratios at mandatory factory stock weight - sans driver, can be faster than a stripped out, lightened, chipped, gear modified, etc., SP-1 car.
Other than superior driving skill, (which, to be sure, can account for a lot), not sure that I understand how an "I" stock car with pretty much a full interior, no chip and stock gear ratios at mandatory factory stock weight - sans driver, can be faster than a stripped out, lightened, chipped, gear modified, etc., SP-1 car.
11-29-2006 | 09:54 AM
#15
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From: Phoenix, Az
Remember however the SP1 car is limited to 225/50 R15 toyos on 15x7 wheels. Even still the SP1 car should win any drag race vs an I stock car and they should be at least close in cornering. I-stock car should be more grip and better suspension, but that should be offset by the heigher weight. I'd figure in long sweeping corners the I-car might have the edge, but in quick transitions the lower weight of the SP1 (944 spec) should overcome the smaller tire.
Hard for me to say for sure since there just are not well build I-stock cars on the west coast. What I will say is that lap times for 944 spec cars have dropped by 2-3 seconds for a 1:15 to 1:40 laps and on 2minut plus laps they have dropped by 3-4 seconds since the series started. This has not been from better prep so much as drivers improvement. At PIR in 2002 a high 1:15 would get you Pole. Now with same cars, but improved drivers a it takes at least a low 1:13 and one driver last weekend cranked out multiple 1:12 laps in near ideal conditions. At Willow springs initial lap times were 1:40 or so, but now this next weekend with POC I'd expect best laps in the sub 1:36 range. Again car development is limited to optimized chassis settings the biggest change is driver development.
Hard for me to say for sure since there just are not well build I-stock cars on the west coast. What I will say is that lap times for 944 spec cars have dropped by 2-3 seconds for a 1:15 to 1:40 laps and on 2minut plus laps they have dropped by 3-4 seconds since the series started. This has not been from better prep so much as drivers improvement. At PIR in 2002 a high 1:15 would get you Pole. Now with same cars, but improved drivers a it takes at least a low 1:13 and one driver last weekend cranked out multiple 1:12 laps in near ideal conditions. At Willow springs initial lap times were 1:40 or so, but now this next weekend with POC I'd expect best laps in the sub 1:36 range. Again car development is limited to optimized chassis settings the biggest change is driver development.