924Board.org

[Joe bar]

Hi there , i´m joe bar , i live in louvain ( in the neigberhoud of brussels ( belgium, europe )) , my intrests are bikes and old or special cars ( those i can afford )and i speek very louzy english .
I bought an old neglected 924 of 1984 with lots of electric problems and a bad painting .
So i started looking for a new cable three , i found one after 2 weeks of searching and geuss what , the person who had the cable three also had lost of stuff of a turbo lying around , so 200 bucks later i drove home with a new cable three, a turbo , the airbox of a turbo the entire exhaust of a turbo and the injector of a turbo .
So here´s my qeustion , will the engine hold it and what adjustments schould i make ? ( or schould i just buy a 924 turbo and #### off with my naive dreams of getting more horsepower out of the 924 n/a )

Grtz ,

joe bar.

[81turbo]

The turbo has a very different set up than the n/a.

A lot more work was done than just bolting on the turbo and exhaust.

The 931 engine has a completely different head design, fuel system, pistons, clutch, transmission, torque tube, brakes (option 1980 standard 1981+) and intake the list goes on and on.

The only real similarity is the bottom end.

I wouldn't try bolting it up!

[Joe bar]

Myeah i know the combustion chamber´s design is totally different and the compression is also lower with a turbo , but i would think about letting the turbo run on 0.6 bar so it would give me about 45 hp´s more and wouldn´t blow the engine .. ( i think )
So i´d like o hear some opinions on that ...

[81turbo]

The turbo engine is basically a whole different design with the exception of the block and crank. The US Turbo cars run .45bar stock IIRC.

Save yourself the trouble and buy a turbo.

Did it ever occur to you that if it were that easy everyone would have a 924 n/a turbo?

Adding HP to the n/a is not easy. If 45hp were sitting there just waiting to be swapped on, you wouldn't be the first person to do it.

[Joe bar]

[morghen]

I guess the euro could handle some boost...but i dont think 0.6 would be acceptable...adding a turbo that wont blow off the engine(low boost) wouldnt give you more power than a NA engine with ported head a valve job and a 10:1 CR
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Supercharger and EFI kits
https://www.the924.com

[Neil924]

Welcome Joe Bar. It would be chaeper and easier to buy a turbo. More reliable also.

Good luck

[My924gtc]

Joe welcome to the board.

I for one disagree with these gentlemen and I say get to work on everything else on your car.

Get the suspension and brakes rebuilt and tuned.

Get the paint and body work (if needed) and the interior back to snuff.

Get everything as nice as can be and then worry about the engine.

By the time you have all that sorted out there will likely be everything you could ever want to make your NA into a much more agressive car with better than 931 performance.

The reliability of your car is dependent upon the quality and condition of the long block. Rebuild it to stock and run moderate boost, or throw some money at it to make it a little more tolerant of boost and crank it up, but do not just abandon it for a 931.

If you buy a 931 expect to rebuild it the same way. ALL THESE CARS NEED COMPLETE REBUILDS so rebuild what you got.
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MJ
'81 924 2.0L T
'82 924 2.3L SC/EFI <---online fall '06

Sponsor of the 944 Cup and Super Cup
Sponsor of the "2006 Battle in the Badlands"

[Khal]

G'day Joe Bar, welcome.

I have a 924 Turbo. It is very different to the NA. Many things are different, not just the engine.

Click here to see some previous threads on adding a turbo to an NA.

Sorry, but my opinion is the same as some of the others: Don't bother, just go and buy a 924 Turbo.
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'80 924 Turbo

[CBass]

You can make a 924 NA fast if you have enough money. There will be a lot of custom work involved, as you can't simply use 924 Turbo parts on a NA 924.

A supercharger is an easier option, a few members have put together custom setups already.

Sell your parts and get to work on a supercharger, and you'll have better results.

As for how much boost the engine can tolerate, I'm running 11:1 compression with the heron head. I wouldn't worry too much about running 0.6 bar of boost on 9.3:1 compression, as long as you run it on the best pump gas available, run a little rich and have the ignition set up properly. An EFI conversion would almost be a must at this point.
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'81 931 in various states of assembly

[timstar92404]

924 turbos are very rare though at least here.... you can't just go out and buy one....you might have to look for years to find one.

I've seen 2 listed for sale in the past few years and one claimed to have a dead battery thats why it was not running and the other said it had electrical problems. even 924 na is rare.
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78 924 sold.
85.5 944

[CBass]

Tim, want me to list the 924 Turbos I am aware of in the area?

My brother bought one in town, '81 Turbo with a ton of work put into it. I got most of one as a parts car a few years back.

Lizard bought two from Kenodog, who himself still owns one, which is for sale. There's also another 931 owner in teh lower mainland, I can't remember his exact handle... I know of a guy who was breaking two of them in the lower mainland as well a few years back.
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'81 931 in various states of assembly

[leadfoot]

Welcome
Get a leak down test done first on your engine as this will tell you how the cylinders are sealing. Use this to base your next move.
Don't let anyone say it's not worthwile in doing modifications to your car, i.e adding a turbo or improving the engine as it will not only a) teach you alot about your car and b) make it a better car.
Running X amount of boost is only proportional to the amount of prepartory work you do first. If your engine is in bad condition then no amount of boost will do any good, it will just make things worse.
Likewise with a well prepped engine who says it can't handle 1 bar boost.
No one on this board has yet to come forward with a 924 they've strapped a turbo too and said X amount of boost killed my engine and this is the limit.
There are many factors not inducive to boost that come into play like... quality of fuel, turbo efficiency, air/fuel ratios and timing, all have to be taken into account when you make the step from N/A to turbo application, plus your skills in manufacturing parts, tuning and probably the most important finances.
My personal believe is that these cars respond well to boost even in small amounts. They also respond well to electrical circuits being of high quality too.
If you can use the otherwise wasted exhaust gas into something more productive, kudos to you... I'm not saying it's going to be easy, but base it on your desired final outcome, if you want reliable street machine, then engine refresh small turbo low boost and you'll be fine.
If you want a gut wrenching stonker pushing out over 300hp then the turbo model would be a better a better starting point.
Leadfoot
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1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

[Khal]

[morghen]

well with these coments i am thinking about not going for higher CR but to put two head gaskets and a turbo on my NA among refreshing the engine and porting the head...

I'm not looking for more than 200 HP(180 would be just fine) from this car SO: with a ported head, big bore TB, freeflow exhaust, big intercooler, high performance ignition system(NGK), and high flow injectors i think that would be doable(maby some pistons ).....then again for that money i'm going to do a trip in germany this summer and buy me a 931 engine from some salvage yard mount it on the NA and kick ass with it on the streets or the track.

Its simple....its not worth it to mod the NA engine for turbo....the money and time you spend will be more than buying a 931 engine...whats worth to do for the NA is port the head add a big bore TB a KNN filter and a free flow exhaust....also lighten it...you could get around 150 HP with the right sparks and ignition timing(plus good gas) and if you lighten the car....man that would be a fast ride ! all this for UNDER 1000EUR

i think for a turbo setup from the NA you will spend over 3000EUR
_________________
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https://www.the924.com