alex

I get your point- its just that almost every time someone brings the issue up, they get shot down immediately. We need to let people experiment and tweak their cars.

Mongo

The problem is in reality, there are people that don't intend to spend lots of money with this experimentation. This results in threads likes this being created and shot down.

Improving upon a Porsche IS NOT EASY, whether it's a 912, 944, 993 or a 997 Turbo. There are constraints on all cars that limit factors of modification. The guys that built these cars are engineers, not just someone that got hired to design and build cars right out of high school.

944CS

You must not be reading the same books as I am. You should read this one:
http://www.amazon.com/Bosch-Fuel-Inj...d_i=0837603005
If i recall correctly, this book states the AFM is restrictive by .5 MILLIBAR. Milli means 10 to the minus 3 power. That is .0441 psi. You lose aprrox. twice that much air pressure just going 1000 feet above sea level.
If the motronic is so praised, why aren't there magic chips out there you ask? How much hp do you expect to gain with a tune when the engine in question has 9.5:1 compression, 8 valves, and a cam with no overlap? The Motronic will do everything you need it to do. Its not the Motronics fault that the stock engine limits volumetric efficiency and the capacity to produce a high bmep.
My disclaimer was put in to say that I am not saying it is the best, thus my use of the words "I am not saying the Motronic is THE BEST". Where did you get the idea that it's easier to make power out of a Turbo with CIS than it is with Bosch LH?
To build the motor I am talking about was over 20 grand in parts/outsourced machine work alone. Earlier in this thread I said it would cost over $20 grand, I never said anything about it being cheap, or easy. If it was easy, everyone could do it. Yes, it is daily driven. It does not idle like a stock car however, that is something you cannot get around with a car that A. makes power at as high an rpm as this car does and B. does not have variable valve timing. It runs on east coast 93 octane.

I hope I was clear with everything. I am not trying to be an ***, it's just some of the things you are saying are completely, just, wrong. But I do not blame you for being skeptical.

DDP, would love to know the CR and projected life span of that motor. Also, is it running above 10K?

Tifo, I understand where you are coming from. But I don't think this car will ever be dynoed so it can prove to everyone here it really is a 200+ hp 8 valve n/a. If you watch this video, you can see the acceleration comparison with a mostly stock 944:
http://www.youtube.com/watch?v=T1ujPOL0jUk

Mongo

944CS, I can understand your defense on Bosch L-Jetronic. I have a book called Tuning and Modify Bosch Fuel Injection that follows the same guidelines as that book. However, it's slightly compressed down into a $23 book found in Borders.

What measuresments are you talking about up there? Are those for the 944? If you look at the intake pipe that it's going into, you can see that the amount of air flowing into that small square opening does not provide effective volume in the boot. (I think it's 3" for the factory intake boot) With an MAF, there is no restriction from a barn door.

You can do amazing things to a 944 engine for $20k. I would go that route if I was very much in love with the car. However, I would rather put that money into a house or a Boxster that has 200+ HP already

944CS

I don't understand what you mean, that hole supports well over 200 hp. Especially on an N/A car, you want to keep things as small as will be sufficient to keep your air velocity up - this is true not just for the head.

alex

Valid point. I would counter with the fact that 944s are based on nearly 30 year old technology, so there is room to upgrade- just not cheaply.

Mongo

If opportunity knocked and I had a budget dedicated to the 944, I'd take that ITB setup I'm making and use TEC-3 engine management to get that sucker to really sing.

944CS

you'll need AT LEAST a cam with longer duration to make it start to open its mouth

cie_lab

+1

talking VERY high RPMs. I wish I knew all the details, but there are certainly formula-type motors in the 2.5 litre range cranking out 500hp+...in the 10,000 RPM range!

If you can keep your motor from Porsche disintegrating, you could probably do it.

But remember, there's a whole lotta gears between 0 and 10,000 RPM.

V2Rocket

If you made anything that rotates as light as possible you could make more power but you'd lose torque. Such a car would be destined for track duty.

Mongo

Why make anything in that motor lightweight? You have almost a 2500cc engine with a 100mm bore and almost an 80mm stroke. You will not get far up the rev range with those specs. In fact making something lightweight with that bore and trying to squeeze 8500+ RPM out of it is asking for catastrophic failure.

944CS

see post #80...I will tell you that is not 7000, or even 8000 rpm....that motor has been together going on a year, numerous track days on it, daily driven. Mongo you need to get out of rennlist world, its much nicer out here.

944CS

here is a copy of an emial Jon Milledge wrote me about 3 years ago. I asked him if he could make me a head/cam combo that made 200 hp with stock compression ratio. I had a low mileage engine that I did not want to rip into.
Chris,

You need to lower your expectations. The best stock type engine I have
ever built made 196bhp with 11.3/1 compression, 1mm overbore, flowing 5
different stock 85/2 on cylinder heads to find the best one with just
the right core shift in the casting, hours and hours of dyno time
developing headers, a digital programable ignition system and much
more. I tried many different camshafts, mine and most of my
competitors. This engine used a 1988 engine as a core.

What can you achieve? I would first want to know why you want to
retain the stock compression ratio. This engine is not knock sensitive
and can safely run over 10.5/1 compression ratio on 92-93 pump octane
gasoline with no problems. This is also prime in improving fuel
mileage and power. With a proper valve job and compression increase,
a camshaft change, a K&N air filter in the stock box, and an exhaust
system upgrade, you can make 175 bhp.

Jon

Mongo

Okay, for one thing, I'm not sure if you're being sarcastic or rude.... I have not seen the youtube video seeing that my work blocks that website. Maybe you can tell me what that motor is redlining at?

I said what I had said up there because I have seen people that hot-rod engines to large bore and high rpm machines only to realize they put money into something that blew up in hours or within 10,000-20,000 miles after the break-in period when they are wound up to the max.

Get out of the Rennlist world? Sure why not! Seeing that only the good people here respond with real information to my threads on here, while the other 95% that respond to them spam it up with misinformation and hijacks.....then again I am in the 944 FORUM.

Mongo

Did you do it? How much was he going to charge? Was it really worth putting 200 HP in a car where the performance would then compromise the reliability of the drivetrain...namely the R&P?

Milledge sells an ITB setup for almost $3,000 and has NO DYNO SHEET on his website with that setup on a stock NA motor. See this is where the argument starts on whether or not exceeding your car's market value 100%-200% is really worth it...especially if you're driving it on the street. Insurance companies will not care if that thing gets wrecked and will still give you low-bluebook if you don't bust your *** giving them receipts for everything to get at least some of your money back.

Racing? sure why not! At least you can stretch your car's performance to the limit.....now reliability yet comes into question....