924Board.org

[dreamgts]

HI GUYS, After a lot of thought and advise given from members of this forum, all of which were considered, I have finally decided on what seems to be a decent setup for my 924 NA 1979 Euro Model. The car will not be street legal since It will be used for local sprint events/ possible hill climbs and a local once a year event were some classic powerful cars get togther and organise what we call the GRandPRIX De Malte. The latter race is a circuit race held on public rounds around our small city which is turned into a circuit for a few days and were most of the competitors drive classic race cars (30years+).
I have no restrictions regarding carpets ,ac, headlights. seats or what ever is classified as extra weight on the car, Im sure this will help too since weight can stop a train as they say. Future add ons to save weight would be a fibre hood/bonnet and doors and rear screen, I still have to look at the weight loss with these items though.

First of all bodywise the car will be given the D Prod look keeping the style as close as possible although I do intend to alter the front spoiler as we call it here. I have also chosen a paint body theme which in my opinion will compliment this look. I might even add on a rear wing to keep the rear wheels close to the ground for traction, this though has to be researched since aerodynamics I believe to be very important to keep the car as steady as possible. I still have to choose tyres but most probably i will go for either Firestone or Dunlop since these 2 seem to have loads of experience in race tyre development, comments here will be greatly appreciated.

I will be using the 924 na head which will have bigger valves . I intend to place 44mm intake valves and 37mm exhaust. A header from MSDA will also be added. I also intend to change the camshaft which I intend to buy from Integral, I still have to wait for Steve's recomendations on this though.

Fuel will be supplied by either twin 40 DCOE or twin 45 DCOE webers. Im a bit quizzed here but have to wait and see what information is aquired by pros in this field, most of them are members on this forum. Fuel pump type would be another consideration in this area since we dont want to starve the carbs do we, especially if we are on the tail of a 911SC

The lower end will be fully balanced while CR will be increased to 11:1 while lightweight conecting rods will be added. Obviously other stuff like special lifters and studs will automatically have to be replaced as well. I am also considering a stroker crank if this adds any advantage to the set up, although my sources tell me that this might not be needed.

As for wheels and rims, I still have see what can be fitted in sizes since the fenders will be added to the body, surely though rims might possibly be BBS or those 5 spoke type 917 lookalikes which I realy like.

In the future I might consider a good cooling system which was also recomended to me, yet this at this point will set the project back, although i would like to go 5 lug too i might at this point consider what was described as a 5 lug spacer instead of the full 5 lug conversion for now, i have to investigate the difference in $$$$ here in order to decide which way to go. I dont want to purcahse some expensive 4 lug wheels now and then decide to go 5 lug after some time, but I do have a budget to keep to.
I am concerned a bit also about the head design where threads here explain that the 924na head as one member put it , has the worst designed head since the side valve engine, so comments are welcome in this area as are in other areas. I havnt decided what ignition system to use yet either. I would go for COPS if This is the best set up for the car and if budget permits but that will have to wait a few months I guess. I am expecting 175BHp with this setup and with loads of weight removed Im sure I could do well. I would be very happy if this was achieved since this is a 924 NA and not a turbo version, since it is an NA I consider my goals to be acceptable for this type of engine. I know I could have opted for Turbo but NA and turbo in my opinion are 2 different engine setups.

I am quite happy with the feed back I got from fellow members on this forum thru other threads I posted and as one might note good advise was considered and taken. I am also glad that the project will start soon although some work has already been done to the car like lightening cleaning up. dismantling etc. most of my time though was spent on considering advise and doing research thru other threads posted and sourcing for parts which could be or could not be used. I learnt a lot in the few weeks Iv been a member here, most of you know what your talking about here.

Thanks
dreamgts ( or is it dreamDProd?)
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2 PORSCHE 924 (CURRENT PROJECTS)
2 CLASSIC CORTINAS (FINISHED)
1 CLASSIC FIAT(FINISHED)
1 CLASSIC FIAT 132 2000CC(JUST PURCHASED)
4 SUV'S
2 SEDANS
1 OPEL PANEL VAN
WIFES SUZUKI ALTO

[Nein37]

As far as wheels are concerned... 7X15 fuchs would be a very good choice, probably the most affordable AND lightest option.
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1981 931 CGT replica, OEM CGT intercooler, .8 BAR WG spring, GTS Headlights, Innovative Wide band A/F, A/C delete, 16" Fuchs, Weltmeister 200lb lowering springs, Bilstein HDs front, Koni Sport rears.

[Joes924Racer]

ahhh wheel choices fuches are nice though for you you could even go with cookie cutters which are nice im sre you know that theres a set for sale here on the board or there was i have not been to that post in a couple of days.. now I want to see the d-prod kit up close so if you can give us pics of the install and stuff. Why not besides tons of advice and info available we all like pictures too. Good-luck
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1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

[daniel]

What rods were you planning to use??

Thanks
_________________
Over the top of skyline, total brake failure.... hit the wall at over 200 kp/h at the dipper, so anyone who has to brake for the esses is a pussy.
1977.5 Race Car, CAMS Group S Spec
1989 944 Cabriolet

[!tom]

You're planning on having 175 hp, and sticking with the stock solid 4-lug rotors in the front on a race track?

In my opinion, an increase in hp dictates the necessity of an increase in braking capacity. An appropriate way to do this is to swap in the vented disks from the 924 turbo, which came from the factory in the same HP ballpark as you are targeting. This is also known as the 5-lug swap.

A bonus is that the rear disks don't need constant adjusting like the drums do, as the drums don't have auto-adjusters.
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78 924 NA
5-lug

[Joes924Racer]

and they grab a hell of alot better ..some say there isnt much diff. though not so on a properly set up 4 wheel disc set up compared to the drums there is a difference.
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1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

[dreamgts]

Hi guys, I did not say that I WONT BE making a brake update, I just said its on hold for the moment in other words, You are right though a 4 to 5 lug conversion is absolutely needed. Its just the second last on the list right now, last are wheels.I want to concentrate on the engine and body right now Fuchs are nice, I found a set of seconds in the USA, they are very expensive to ship though since Im located in Europe. I do like them too though. Any have experience with tyre grip, I was also considering 16in wheels, any advise on this. Maybe 16 are better than 15in? Wheels are last since I need to try out sizes against the fenders. I will be posting some pics when started, at the moment I am taking some pics and saving on disc for future uploading, but nothing dramatic for now.

dreamgts
_________________
2 PORSCHE 924 (CURRENT PROJECTS)
2 CLASSIC CORTINAS (FINISHED)
1 CLASSIC FIAT(FINISHED)
1 CLASSIC FIAT 132 2000CC(JUST PURCHASED)
4 SUV'S
2 SEDANS
1 OPEL PANEL VAN
WIFES SUZUKI ALTO

[924RACR]

16's are just dead weight, unless you're planning on going to 944 Turbo brakes... but why would you need that much brake on such a car? Stick with the 15's, you'll get better gearing outta them.
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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[dreamgts]

[ideola]

Regarding your question on the head and intake, most of the problem is in the head, and if you go with carbs, you'll be getting rid of any problem with intake restrictions. Here is a good discussion on carb sizing (scroll down to get to the good stuff). I can't comment experientially regarding your intended use, but it looks like either the 40s or the 45s would be suitable, with perhaps a slight preference toward the 45 for a track-only car. Remember, the NA intake port is only 36mm...(not to be confused with valve sizing...). Might be good to get Vince Ponz and Chrenan to chime in here...
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erstwhile owner of just about every 924 variant ever made

[dreamgts]

[dreamgts]

Seen that discussion Dan both Chrenan and Vince run 45's. bassgt mentions some sort of tapered manifold which would be good to investigate on. Think I'll go back to work and do some serious investigating.

dreamgts
_________________
2 PORSCHE 924 (CURRENT PROJECTS)
2 CLASSIC CORTINAS (FINISHED)
1 CLASSIC FIAT(FINISHED)
1 CLASSIC FIAT 132 2000CC(JUST PURCHASED)
4 SUV'S
2 SEDANS
1 OPEL PANEL VAN
WIFES SUZUKI ALTO

[Fifty50Plus]

As Vaughan said, go with the 15s. And, don't worry so much about wheel spin. I have two race cars with more than 175 horsepower and run on 15 inch rims and street tires. I've not spun the wheels on anything but dirt.
Chuck
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1979 924 NA race car H-Prod SCCA
1982 924 NA race car - Sold
1981 924 Turbo sold
1982 924 Turbo sold
1972 911 E race car - traded for Cayenne Diesel
1975 914 1.8 Building for H-Prod SCCA

[ideola]

[dreamgts]