944 S Track Day Project

[Marcussuper7]

Hello all,

I have just purchased a 1987 944S with the intension of converting it to a track day tool. I collected the car last weekend and felt a liitle dissapointed with the performance. I know the car is nearly 22 and has done 103K but it feels a little underpowered. The car seems to have loads of torque it drives very nicely at low rpm and pulls well. As the revs rise there seems to be no gain in power as you would expect?

I am looking for any advice as to what could be causing this are there any simple checks that could be made or any common faults I should look for?

I will be posting my progress of the track conversion shortly.

Thanks

Marcus

 

[Peter Empson]

Hi Marcus and welcome!
That sounds a little odd, most people complain about the lack of torque low down, and there should be a noticeable step at about 4k. I'd simply start by giving it a good service to make sure you know where you're starting from. If it's still down on power then it will probably benefit from a top end rebuild (odds on it'll need a head gasket anyway). Once you've stripped the weight out of it it will feel a lot more sprightly, I'd also think about fitting the Lux box (I think the 'problem' with the 944S is that it's too long geared), this should increase acceleration and be more suitable for track use (these boxes can be a little delicate, but if you avoid standing starts then you should be fine).

 

[333pg333]

Get it diagnosed by someone who knows these cars. I'd echo Peter in saying reducing weight will give a decent improvement and if you can afford it definitely get a gearbox with a shorter ratio or even fit a crown wheel and pinion from another one that will give the same result.....or sell the car and get a turbo...oops, did I say that out loud?[&:]

 

[Diver944]

Is it definately an S? Over the years I have seen a few 8v Luxes badged up as a 16v S []

Easiest way to tell is to post us a picture of the cam cover - the 16v is about 8 inches across and normally painted beige, the 8v is about 4 inches across and bare metal.

 

[Marcussuper7]

Thanks Guys,

It is definately an S It has the larger beige 16v cam cover.

It is a little odd, there is no signs that the head gasket needs doing. The car just doesnt get any extra power at 4000rpm. It still pulls ok just no more than at 3000rpm. I am going to start stripping it this weekend but if i am still unhappy with the performance then I may have the cylinder head ported and polished. Good Idea?

The Car also has Boxster 16" wheels on it which isnt helping. I think the tyres are 225 55 16. Too big? What is the optimum tyre size for the 944?

Also which crown and pinion should I be looking for? and where from?

 

[Diver944]

ORIGINAL: Marcussuper7

I may have the cylinder head ported and polished. Good Idea?

I think you need to find out if there is a problem first before trying to modify the flow. A simple Dyno test could give you an indicator if it is down on power, an S should be achieving 190bhp at 6000rpm when it left the factory but quite a few seem to be down on that figure nowadays. I have heard of a theory that the valve stems are so long that minor wear can cause quite a drop. Call Barry Hart at www.hartech.org.uk who has written about this before, he has also mentioned bad timing can rob a lot of power with this variant of engine.

Standard wheels were 7x15" wearing 195/65VR15 though you could have the larger 16" versions as an option. If your tyres are 225/55/16 then the rolling radius is only 1cm taller and could not make much of a noticeable difference. When they do wear out you should replace them with 225/50/16 which are virtually identical in circumference to the originals

 

[xenon]

Done a compression test?

 

[barks944]

You probably wont gain much from a port and polish from what Ive read. A dyno run would be where I would start. I got one free the other day and it took 10 mins so I't cant be that expensive to get done.

 

[Peter Empson]

If you're anywhere near me (Aylesbury) you're welcome to come out in my car to see if it feels different from yours (mine is down on power, but still feels pretty potent for what it is). I echo the comments about getting it on a dyno, the most I've paid is £60 for a run, but pay cash and time it right and it'll probably be less.

The headgasket may be fine now, but my experience is that after a few trackdays (cycles of high temps) it will probably start to weep if it's original, I'd fix it when it happens unless you need to take the head off for another reason, but it's worth budgeting for anyway. I too doubt there's much to be gained from a port and polish (did it years ago on my 8v Lux and it wasn't hugely beneficial from memory). I think the main loses in the 16v heads come from wear to the valves/mating surfaces.

If they're genuine wheels then they're fine, if they're replicas then they will be heavier which can dent the performance a little.

I wouldn't rush with the gearbox unless it's faulty, try it a few times and see how you get on, you may decide you want an LSD for example, so best to try to do everything at once I reckon. A used Lux box which has the closer ratios (but no LSD - they're rare in most 944's anyway) can be had for as little as £100 and would be worth trying if you want to experiment.

 

[944 man]

ORIGINAL: Marcussuper7

Hello all,

I have just purchased a 1987 944S with the intension of converting it to a track day tool. I collected the car last weekend and felt a liitle dissapointed with the performance. I know the car is nearly 22 and has done 103K but it feels a little underpowered. The car seems to have loads of torque it drives very nicely at low rpm and pulls well. As the revs rise there seems to be no gain in power as you would expect?

I am looking for any advice as to what could be causing this are there any simple checks that could be made or any common faults I should look for?

I will be posting my progress of the track conversion shortly.

Thanks

Marcus

944Ss are always a disappointment. You really have to ring their neck to make decent progress. Even Porsche admitted that they were overpiced and failed to deliver...

 

[Peter Empson]

ORIGINAL: 944 man

944Ss are always a disappointment. You really have to ring their neck to make decent progress. Even Porsche admitted that they were overpiced and failed to deliver...

I would have to disagree with this, I have used all variants of the naturally aspirated 944 engines for a decent number of miles so I can speak from experience and do not see it that way. A different approach to driving is necessary, but I would never call it dissapointing when driven correctly, in fact it's more of an event than the Lux thanks to the way the power chimes in.

I also think the 944S is a great candidate for a track car, it's apparent lack of torque (which I feel is really a gearing issue as mentioned previously) will not be a trouble as you wont be out of the power band anyway (except on possibly some of the mikey mouse corners at the Bedford GT track).

Just my 2 pence worth...

 

[944 man]

Personally I like the 944S but I realise that it might not come across that way. You really do need to thrap them though, which most people fail to appreciate: this leads to the disappointment.

Simon

 

[Fen]

I've not driven one, but it sounds a lot like the 8v vs 16v Golf GTI. My preference being the 16v.

 

[bigbadtez]

If i was you i'd have it hooked up diagnostic machine.If there's something wrong with the electronic side of the engine then this will show. You may have blocked injectors or a dodgy MAP sensor.Its costly to do it from start to finish by elimination but at least if you plug her in you'll save time and cash pin pointing the problem

 

[Marcussuper7]

Thanks again for your views.

I live in Southampton does any one know of somewhere affordable I can have it plugged in and diagnosed?

 

[Peter Empson]

I don't know the area that well, but it's be worth speaking to John Mitchell (http://www.jmgarage.com/) in Christchurch as he knows 944's and has a very good reputation.
I hope it's something simple like an incorrectly adjusted throttle cable []