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First Race Weekend

 
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MikeJinCO  



Joined: 08 Jun 2010
Posts: 794
Location: Maysville, Colorado

PostPosted: Thu Aug 22, 2019 9:46 am    Post subject: First Race Weekend Reply with quote

A quick review of first race wekend at High Plains Raceway 50 mi. east of Denver CO. My experience one driver school weekend and one track day in street 924 and one track day, about 10-12 laps in my home built 933 replica race car.

Friday-had to bed in brakes(Hawk HP+, couldn't get full set of either KFP of R4's). I had never been around this track before. Studied layout and utube a bit, with no experience utubes not much help as no overall perspective is available. Track has 15 turns including 2 downhills, one 10% climb turn and some Esses. I at least found my way around it a bit, No idea of lap times. Had 30 psi in tires(Nitto) and got them to 32 and found out with 944 brake system it really stops. Lap days are tough as I'm slow and folks in A Sedans(600hp Mustangs) Corvettes and Vipers are unbelievably fast-and scary.

Saturday started at back of pack(30+) as rookie and could barely keep up on the pace lap. Pushed as hard as I could but fastest lap of 3:14(good folks 2:10). I was terrible in most turns really rather discouraging in the morning. In the afternoon after talking with my now up to 4 volunteer instructors I learned to move hands on steering wheel in #6 while braking to get around the turn, got uphill 7 faster nd hairpin 8 better, The esses at 9 were better and actually hit the rev limiter(6000) on the up hill. Even 400 rpm faster on the straight. Took 11 seconds off the time. Tire pressures got up to 35(supposedly 34-36 the sweet spot). But oil temps too high.

Sunday: Morning only as afternoon canceled due to windstorm. i got many of the turns better, learned to downshift after braking and steer wheel shift in 6, better but still bad. I improved greatly in the esses sections and actually was able to follow people in turns to find out their lines better. Got another 11 seconds off. to get to 2:52. I got lapped 2 times by the good guys in 20 minutes rather than 2 times in 15 minutes.

Overall: The car seems to handle wonderfully, with my 968 30mm front sway bar with the Weltmeister 22mm rear and GAZ suspension (I not sure I would recognize a problem if I had one). Oil Temps are way too hot, I'm going to remove that Derale thermostat, it might be in backwards as they may have published the directions wrong. The brakes worked wonderfully, no noise, but tons of dust. My driving school instructor in a Spitfire(2:20 laps) knew my lap times before I did. The only criticism was "stay on the line", don't be a nice guy and get out of the way. I very much enjoyed the weekend. This last time out I was fast enough to follow people a bit and that really helped.

Hopefully I can get to the final race of the season at La Junta CO, an old ir force base flat track. I'm worried about the cam followers due to the oil temps, and I can't get enough camber on the driver rear.

Sorry about any spelling and grammar errors.
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Mike
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Fasteddie313  



Joined: 29 Sep 2013
Posts: 1756
Location: MI

PostPosted: Thu Aug 22, 2019 11:26 am    Post subject: Reply with quote

By your times it sounds like you made a huge improvement!
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KDJones2000  



Joined: 14 Sep 2010
Posts: 317
Location: Phoenix, AZ

PostPosted: Thu Aug 22, 2019 12:18 pm    Post subject: Reply with quote

Mike, this may help you get up to speed faster:

https://www.goodreads.com/book/show/227551.Going_Faster_
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CÚdric  



Joined: 27 Aug 2004
Posts: 1870
Location: Sweden

PostPosted: Thu Aug 22, 2019 4:21 pm    Post subject: Reply with quote

Great fun to read about your way into racing. It sure is a long way to get up to maximum speed, some get there quickly and some need more practice to get there. Great idea to get some instructions, that really helps. Maybe you can go to some events/practice days and get professional instructor help, that would probably get you up to speed even faster.


Other than instructions, when you get faster a really really good investment would be to use race chrono/Harrys lap timer and a hood GPS dongle (5hz or more) to do some logging. It can really help you understand what you do and where, and better still if an instructor could drive your car for some laps with the logger. Then you would have some great reference data to compare with, (and maybe sharing logs with other people in the race series). And also get some feedback on the setup of the car. A camera in the car is not a bad idea either, its very hard to remember everything you do in the car, and some things you do without even noticing them, so looking at
what you do afterwards can great aswell. I have been helping out as instructor a couple of times for friends and helping them with log analysis to get faster, its fun!

Being mentally prepared on what to do is also important, the book recommended above is no bad idea. And also to think through the next session before you get in the car, and think through what you do in the every corner and what you want to do differently next time your out on the track (ok, your tracks are really long compared to ours, so maybe focusing on some specific corners per session is a better idea)

How high where the oil temp? And where did you measure it?

I hope we can follow your future adventures in the car !

And yes, the Hp+ are really really dusty, but otherwise a great pad !
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peterld  



Joined: 10 Dec 2006
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Location: Noosa Heads QLD Australia

PostPosted: Thu Aug 22, 2019 4:44 pm    Post subject: Reply with quote

Well done Mike. Yeah it's a steep learning curve, but you're still smiling.......and that's what counts!
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MikeJinCO  



Joined: 08 Jun 2010
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Location: Maysville, Colorado

PostPosted: Fri Aug 23, 2019 10:31 am    Post subject: Reply with quote

Yes I'm still smiling. I learned a lot and still have to get more comfortable with the car, I really didn't push it terribly hard. Saturday i was about 4000rpm on the straight then up to 4400 Saturday afternoon and Sunday. Driving hard I probably could have gotten up to 4800, but I was also messing with braking points so that extra 400 might have gotten a little spooky. That will just take more seat time. Thanks for the suggestions and it is good to hear about the Harry's lap timer as I have looked at the sophisticated data loggers and can't handle the cost right now. The concentration that I had during driver school in April isn't there as some outside issues have arisen that make the racing just a diversion and it showed as I would take it easy on some corners.

Trying to get better at all the corners at the same time is quite difficult. They say to concentrate on really getting one corner right at a time and I was really working at #6 and #8 as they are two of the most difficult and It showed particularly at #8 as the esses at 9 and 10 improved dramatically. #6 still has too many things going on at once, but I sensed gradual improvement-at least in organization.

My oil temp coming out of the motor before the remote filter and cooler got pegged at 250F. The cooler is the same as RACR's.

Some specs: CR is about 10:1 931S2 pistons with valve pockets and .055 Cometic head gasket. Head mildly ported(smoothed edges) and port matched with Elgin 66-15 264 deg cam. MSDS header. Balanced with stock clutch and flywheel. 45mm Webers w 36mm venturi(probably too large for the NA head). Webers not tuned at all. Distributor at about 40 deg adv at 2500 rpm and up. 6000 rev limiter on MSD 6AL ignition.

Tranny is a 1978 4 Speed, 3.88 axle ratio. 5 speed won't fit due to fuel cell .

Suspension is GAZ Gold with 400lb front springs and 275 coil over in back with 23.5 TB, for a net of 400/280 or about the same as the 1980 cars. Weight iI don't know but guessing about 2200 as car is completely stripped. Tires 205/50/15 Nitto 01 on 7" cookies. Brakes are from an early 944 with 944 booster and MC and appropriate F-R brake line design.
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CÚdric  



Joined: 27 Aug 2004
Posts: 1870
Location: Sweden

PostPosted: Fri Aug 23, 2019 5:37 pm    Post subject: Reply with quote

Seems like a good setup, I would however really try to get that 5 speed in. The performance benefit is worth more than alot of engine tuning. We did that on a friends 924, and checking the logs from the track was really surprising, so much faster out of some corners.

That oil temp isnt a catartohpe, a stock one is about 120-130C (266F) in the sump, my turbo also creeps over 120C at the track. But with your fairly low tuned engine you should be able to keep it below that with an oil cooler.

Logging systems can be very very expensive, however the basics (phone+high speed GPS dongle) is alot of bang for the buck. You can also make a nice fixture for the phone on the dash if you want to keep track of the timing, and predicted lap timing in real time. Its a very common setup here among the club racers/track day people.
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MikeJinCO  



Joined: 08 Jun 2010
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Location: Maysville, Colorado

PostPosted: Fri Aug 23, 2019 9:02 pm    Post subject: Reply with quote

The 5 speed might fit, howeer I'd have to take out the fuel cell to install and remove it at a minimum as no room to pull it back with the cell en place(and ATL 8 gallon). The advantage I see is primarily the 4.11 ratio as that would change things a lot. Also with the number of shifts I missed the 944Only short shift linkage would really help. I already have a winter list of projects that is pretty large. I will add on the smart phone lap timer.
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924RACR  



Joined: 29 Jul 2001
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Location: Royal Oak, MI, USA

PostPosted: Fri Aug 23, 2019 9:22 pm    Post subject: Reply with quote

Yeah, for only the track car - hard to justify the effort to change the cell to swap in the 5-speed. But for competitive use, yeah, hard to stand it without.

We were running 250F oil temp peak this past weekend we had the #77 ITB car out (until it popped the headgasket again), not ideal temps but those are typically the highest it sees, and usually tops out at around 230 or so. Measuring in the same place, too.

Of course, as you run the motor higher in the revs, that'll creep up a bit. We're running right to 6000rpm shift point (redline isn't worth it).

I'm very much not a fan of Hawk brakes - KFPs are much better, the golds last forever and never eat rotors like the Hawks.
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MikeJinCO  



Joined: 08 Jun 2010
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Location: Maysville, Colorado

PostPosted: Sat Aug 24, 2019 10:19 am    Post subject: Reply with quote

Removing the cell is not that bad for me as I cut out the back deck and built a 1" sq tube frame all around the inside rear including boxing in and welding the tranny carrier in place. So I have an aluminum deck held in with Dzus fastners and it really is just remove the deck, an electrical ground wire an fuel line, then 2 bolt on clamps hold the cell in. Then the 5 speed fits, I just can't install it with the cell in place. This one is a like to, but not my highest priority.

When I called multiple sources, I couldn't get the front brakes in either KFP or Porterfield R4, the rears were available from both. Hopefully the HP+ won't eat rotors like the other Hawks do, Cedric says they don't.

I'm going to remove the oil thermostat and see what happens as I can easily get to the oil cooler to blank it off if the weather is cold. If it is still hot I'll have to upgrade my gage from the 250 to the 400. I have the cowcatcher Dp front end on that was used in '80-81. The oil cooler is in the hole in front. I do need add a rock screen there.
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CÚdric  



Joined: 27 Aug 2004
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PostPosted: Sun Aug 25, 2019 6:38 am    Post subject: Reply with quote

Could be a good idea to seal of the air passages around the oil cooler, dependingon how it is installed. To get maximum flow through it.

Ia haven't had the need (yet) for a more agressive pad than the hp+ when i had my na or the turbo. So i don't know those pads. But i haven't had especially high wear rate on the discs, they have lasted a long time, and are fairly cheap to buy new anyway. My only issue has been massive amounts of dust, but that's more an esthetical issue
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924RACR  



Joined: 29 Jul 2001
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PostPosted: Mon Aug 26, 2019 12:51 am    Post subject: Reply with quote

MikeJinCO wrote:
When I called multiple sources, I couldn't get the front brakes in either KFP or Porterfield R4, the rears were available from both.


That doesn't make sense, presumably they don't realize they're a 944 brake?

I source mine from Averill Racing... though I have heard the gold compound is being replaced/phased out...
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Fifty50Plus  



Joined: 28 Feb 2008
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PostPosted: Mon Aug 26, 2019 2:06 am    Post subject: Reply with quote

I get my R4s directly from Porterfield.
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MikeJinCO  



Joined: 08 Jun 2010
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Location: Maysville, Colorado

PostPosted: Mon Aug 26, 2019 10:02 am    Post subject: Reply with quote

I believe i talked to Averill and definitely talked to Porterfield. I'll see how long these Hawk's last. So far they are be better than my braking/driving ability. I did not get them hot enough to produce any fading yet.
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