Stage 0 and Stage 2 ProMAX mods to 944 Turbo - long post
Discussion
I bought my 1989 944 Turbo earlier this year and noticed that it was running a bit rich and misfiring slightly at about 2000 rpm. I looked at the air filter and the HT leads and concluded that they had probably not been changed since the car was new!
A quick trawl of the web brought me to the ProMAX site and after a lengthy conversation with Andy I bought the ignition tune up kit comprising HT leads, distributor cap, rotor arm and spark plugs. I also bought the vacuum kit as some of the vacuum lines had seen better days. I also noticed that the car had been fitted with a stainless exhaust, a Hayward & Scott 3" system I believe although there are no markings on it to indicate the manufacturer.
Before fitting anything new I took the car to my nearest Dyno at the Mini Centre in Sleaford - very friendly - to get a baseline from which I could judge whether any of my modifications were actually making a difference. The original trace is below and as you can see there's definitely a hiccup at about 2000rpm. Peak torque is about 190 lb ft at 5000rpm with peak power of 187bhp arriving at just under 6000rpm. All readings are at the wheels.
Fitting both kits took about an hour and was very easy. The pictures below show the state of the air filter, HT leads and distributor cap as they came with the car - yuck.
Another trip to the Mini Centre and as you can see below there has been quite a nice improvement. Peak power remains about the same but is developed at 6000prm. The torque curve has filled out and is now almost flat from 3400rpm all the way to 6000prm. Also, the erratic behavior at 2000rpm has been replaced with a smooth curve. All in all a nice improvement for not much money and an hours DIY fitting.
On the road the lack of misfire and fatter torque curve were immediately apparent. The car was much nicer to drive, less jerky in traffic and with more overtaking oomph.
So that was "Stage 0" or bringing the car back to something like a factory standard state.
However, I wanted more and I was still convinced that the car was running quite rich. Another long conversation with Andy at ProMAX and I decided to go for the "Level 2" treatment as the best compromise between money spent and gains achieved. The Level 2 kit comprises: dual port waste gate, manual boost controller, new bypass valve, 3 bar fuel regulator and ProMAX Motorsport chip. Fitting of the Level 2 kit takes a day and is beyond my meagre DIY talent so I booked the car in to ProMAX for them to perform the upgrade.
Upon arrival at ProMAX I was impressed by their new premises. Andy, as friendly in person and on the phone, ran through the work to be carried out with me and then sent me on my way with the keys to the courtesy car. Things did not go entirely smoothly but that was only to be expected with an 18 year old car. The rich running was traced to a faulty MAF unit which was duly replaced with a reconditioned one and there was a small leak in one of the hard pipes in the induction system, once again replaced with a recon. When I came to collect Andy seemed very please with the car so I couldn't wait to drive it and to get it onto the rollers at the Mini Cantre.
Well I didn't need to go far to feel the difference
WOW is all that I can say. I drove the first hour with a fixed grin and am surprised that I wasn't stopped on suspicion of partaking of recreational chemicals! Once the rev counter reached 3000 warp drive was engaged and the scenery was just thrown at me. Overtaking had become a breeze in any gear and the biggest danger was hitting three figure speeds far, far too easily.
The rollers at just confirmed what my buttocks already knew - massive increases all round. At 3800rpm torque peaked at 233 lb ft (up from 156 lb ft originally, an increase of 77lb ft or 49%!!!). The torque then dropped off but stayed above 200 lb ft all the way to 6000rpm. Similarly, at 3800rpm power was up to 170bhp (from 114bhp originally, an increase of 56bhp or 49%!!!). Peak power of 233bhp came at 6000rpm. Once again all readings at the wheels.
There are two traces below both showing the original situation with no mods against the Level 2 kit. The first is in 4th gear and is valid to about 5000rpm. The chip is mapped to produce peak power and torque in 4th but the Dyno at the Mini Centre is only rated to 140mph and as the 944 has tall gearing, they lifted off at about 5000rmp - hence the odd trace above that point. The second trace is in 3rd gear just to show the top end.
In conclusion I should like to thank Andy at ProMAX and Steve at the Sleaford Mini Centre and to say that I am in no way connected with either establishment other than being a very satisfied customer
A quick trawl of the web brought me to the ProMAX site and after a lengthy conversation with Andy I bought the ignition tune up kit comprising HT leads, distributor cap, rotor arm and spark plugs. I also bought the vacuum kit as some of the vacuum lines had seen better days. I also noticed that the car had been fitted with a stainless exhaust, a Hayward & Scott 3" system I believe although there are no markings on it to indicate the manufacturer.
Before fitting anything new I took the car to my nearest Dyno at the Mini Centre in Sleaford - very friendly - to get a baseline from which I could judge whether any of my modifications were actually making a difference. The original trace is below and as you can see there's definitely a hiccup at about 2000rpm. Peak torque is about 190 lb ft at 5000rpm with peak power of 187bhp arriving at just under 6000rpm. All readings are at the wheels.
Fitting both kits took about an hour and was very easy. The pictures below show the state of the air filter, HT leads and distributor cap as they came with the car - yuck.
Another trip to the Mini Centre and as you can see below there has been quite a nice improvement. Peak power remains about the same but is developed at 6000prm. The torque curve has filled out and is now almost flat from 3400rpm all the way to 6000prm. Also, the erratic behavior at 2000rpm has been replaced with a smooth curve. All in all a nice improvement for not much money and an hours DIY fitting.
On the road the lack of misfire and fatter torque curve were immediately apparent. The car was much nicer to drive, less jerky in traffic and with more overtaking oomph.
So that was "Stage 0" or bringing the car back to something like a factory standard state.
However, I wanted more and I was still convinced that the car was running quite rich. Another long conversation with Andy at ProMAX and I decided to go for the "Level 2" treatment as the best compromise between money spent and gains achieved. The Level 2 kit comprises: dual port waste gate, manual boost controller, new bypass valve, 3 bar fuel regulator and ProMAX Motorsport chip. Fitting of the Level 2 kit takes a day and is beyond my meagre DIY talent so I booked the car in to ProMAX for them to perform the upgrade.
Upon arrival at ProMAX I was impressed by their new premises. Andy, as friendly in person and on the phone, ran through the work to be carried out with me and then sent me on my way with the keys to the courtesy car. Things did not go entirely smoothly but that was only to be expected with an 18 year old car. The rich running was traced to a faulty MAF unit which was duly replaced with a reconditioned one and there was a small leak in one of the hard pipes in the induction system, once again replaced with a recon. When I came to collect Andy seemed very please with the car so I couldn't wait to drive it and to get it onto the rollers at the Mini Cantre.
Well I didn't need to go far to feel the difference
WOW is all that I can say. I drove the first hour with a fixed grin and am surprised that I wasn't stopped on suspicion of partaking of recreational chemicals! Once the rev counter reached 3000 warp drive was engaged and the scenery was just thrown at me. Overtaking had become a breeze in any gear and the biggest danger was hitting three figure speeds far, far too easily. The rollers at just confirmed what my buttocks already knew - massive increases all round. At 3800rpm torque peaked at 233 lb ft (up from 156 lb ft originally, an increase of 77lb ft or 49%!!!). The torque then dropped off but stayed above 200 lb ft all the way to 6000rpm. Similarly, at 3800rpm power was up to 170bhp (from 114bhp originally, an increase of 56bhp or 49%!!!). Peak power of 233bhp came at 6000rpm. Once again all readings at the wheels.
There are two traces below both showing the original situation with no mods against the Level 2 kit. The first is in 4th gear and is valid to about 5000rpm. The chip is mapped to produce peak power and torque in 4th but the Dyno at the Mini Centre is only rated to 140mph and as the 944 has tall gearing, they lifted off at about 5000rmp - hence the odd trace above that point. The second trace is in 3rd gear just to show the top end.
In conclusion I should like to thank Andy at ProMAX and Steve at the Sleaford Mini Centre and to say that I am in no way connected with either establishment other than being a very satisfied customer
I'm not sure what the wheels are. I bought them for £40 off eBay and had them refurbished in black with a shadow silver rim. They're split rims and I suspect that they're Speedline 2308 sc.
And this is a picture of the Speedline 2308 sc
The thing that makes me dubious is that on my wheels the spokes flare more as they approach the rim and the valve is set partially into the centre part between two spokes...
And this is a picture of the Speedline 2308 sc
The thing that makes me dubious is that on my wheels the spokes flare more as they approach the rim and the valve is set partially into the centre part between two spokes...
Exactly why I went for the 951! Can't wait to get mine up to speed. Last time I went up against an S2 it blew me into the weeds. Thanks for posting that info.
At them moment I am concentrating on getting it up to TUV passing specification. Looks like it needs the new cat fitted. Lucky for me it came with the car.
At them moment I am concentrating on getting it up to TUV passing specification. Looks like it needs the new cat fitted. Lucky for me it came with the car.
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