blown 944

You certainly are!!!!

Having felt over 30 psi myself, I fully understand the tire issue.

Curious about your tune using mixed fuel, particularly timing. I would like to compare to what I have run with E85.

Could you PM me specs if you would like to keep it offline?

lee101315

I have had a few dsms, I had an 1G AWD with a 20G turbo, and I still have a 2g GST with a big 16G turbo.

Heres the plus side of dsms. For close 2,000 bucks, you can buy a 16g or 20g turbo, dsm link, a full exhaust, and larger injectors. 350WHP is no problem.

The problem is stopping and handling, which will clearly not match the cheap but substantial power increases.

DanaT

Agreed. The 951 handles better, stops better, looks better, and just feels like a better car.

It just seems that they engines are hard to extract power from on a reasonable budget. Of course I guess that is part of Porsche ownership.

The DSM doesnt handle that poorly though.

-Dana

Lorax

It didn't take a whole lot for me to get to 350rwhp

A vitesse kit... that's about all. I was still using stock exhaust with cat delete then as well. I was running 20-21psi on pump gas.

blown 944

Sorry I missed your reply,
Yes I am running a holset. I have tried a few different ones. Honestly, I like them, however even the smaller h1c doesn't spool anywhere near what you are talking about. They are also really only good for high boost IMO they come alive big time after 18 psi. I should say though that I am still running the T4 hotside albeit the smallest .48 twin entry. There may be better spoolup with the T3 and some may flow enough I just haven't tried them yet. If you have read any of my recent threads you know I have been trying to lower the spoolup through various methods while retaining the big compressor wheels.

So far the twinscroll piping has felt the best other than the blocked entry valve (which I haven't fully done)

For an off the shelf turbo though, it seems to me that the gt30 or 35 is hard to beat (read "want" just don't want to pay )

I am finding it hard to get the same spoolup as the DSMs regardless. Partly b/c of turbo location and partly due to the 8v flow characteristics. I have recently looked at logs of a particular DSM here at altitude and even with the larger wheel it has quicker spool.

As far as me working on it ...well ... do you have a backup...JK. There should be some very interesting things happening locally for tuning (not from me myself, but I am involved) to help you along. Especially if you commit to E85.

944obscene

The problem with the 8v head is the spool up. It doesn't help that the exhaust headers we use, put feet of piping between the head and the turbo. I'm sure "light-up" and spool would improve with a short runner design. But that would be at the expense of high-end flow. So you kill your low and mid-range a little bit. And keep in mind that the k26 and k27 are journal bearing turbo's from the 80's. THAT is old school.

Although, I'd take the engineering behind the 951 over the 4g any day. Ceramic coated exhuast ports, sodium filled valves. You can have your "stronger feel". From my personal experience, I've pulled a number of cars with higher peak power numbers, simply because the 951 makes torque. I'm convinced that is a determining factor. And I feel my car does great as soon as the turbo lights. It just pulls.

With a #8 hot housing and a 27 compressor, you should be able to make great power. There are plenty of powerful 951's, but the masses seem to run aroun 300-350whp. Not shabby. And look at the torque behind the numbers.

DanaT

Yes. Agreed the 951 makes decent torque.

What I feel a big differnce is "thrust". The motorcycle world is using this now. Although a a 1000cc sportbike and a 1300-1400cc (Think Haybusa or ZX14) just have a ton more thrust and feel much faster even though they are not much faster (relative). The motorcycle magazines are "measuring" this but I dont know how. I am not even sure if "thrust" is the correct term. I think what they are measuring is some sort of combination of hp and torque.

-Dana

DanaT

Here is what sportbike mag is defining as thrust:

"You're on the right track in thinking a higher dyno number doesn't mean a quicker bike, but horsepower does not multiply through the drivetrain. Manufacturers list horsepower as measured at the crankshaft, and this number is typically 15 percent higher than what we measure at the rear wheel with our SuperFlow dynamometer. The clutch, gearbox and final drive all add friction, reducing horsepower at the wheel.

However, the torque of the engine can be multiplied through the gearbox and translated to a driving force, sometimes called thrust, at the rear tire's contact patch. Check out the thrust chart included in this issue's literbike comparison test, and you'll see that thrust is higher in the lower gears than the higher gears, even though each bike's torque and horsepower are unchanged. This is how a bike with relatively low power and short gearing can be quicker than a bike with more power and taller gearing. There is no free lunch, though. Changing final gearing, for example, will give more thrust at lower speeds but less at higher speeds as the engine runs out of revs earlier."

I believe that the "thrust" of the 951 is what makes it feel really fast but also what hurts it off the line. It has pretty tall gearing.

-Dana

944obscene

Well the gearing is not friendly for low-speed driving in the 951. The 951 will pull strong in every gear, even in stock form. From probably 2nd to 5th. The car doesn't do well in 1st or maybe a little bit of 2nd due to "lighting" and spooling issues. I can tell you that the gears make the car "seem" slower than it actually is. So the "thrust" feeling would be more present in your mitsu.

The 951 is geared to take advantage of its torque. Thus the long gears seem to last forever, but its moving quick. So maybe its not a question of the motor's power potential or mid-range feel, but more of a question of which car will actually be faster down the back stretch or up top, where power is going to matter. And power under the curve is a big deal. Sure a B16 can push 400whp in some EK coupe Honda, but how wide is that powerband? In a real race between that and another car with less peak power, but more overall power and torque (say a 944 turbo), the Civic is going to spend a lot of time in last place.

TurboTommy

"Thrust" they use is just another way of saying "torque to the ground" which will manifest itself into acceleration; there's nothing else to it.
And yes, of course, this will be more in the lower gears as opposed to the higher gears; basic engineering. It almost sounds like this magazine is talking to the basic entry level bike enthusiast.

I think our cars feel fast (they are fast) because they got a good area under the curve, are not that heavy, and actually have very good gearing. 5th gear can easily rev past its' 6,000rpm stock power peak, and all gears are spread evenly down below that. (That's actually shorter gearing than most manufacturers, and that's what you want)

lee101315

I drive fast. I am not that jerkoff speeding around in town, or cutting through traffic recklessly, no. But a night when I want to open the car up on a free highway, or drive through a mountain pass, I need a car like the 951. I hated driving the Eclipse faster than 120. If you ever had to slam on the brakes at that speed in that car, you'll know what I am talking about.

For safe high speed crusing, Ill take my 951 out.

If you want to burn rubber and run a fast 1/4 time on a budget, modify the eclipse. Just dont crash

DanaT

I think what they are really trying to quanify is the instaneous dv/dt (or acceleration). The torque of the big bikes just makes the acceleration mind numbing and compared to a smaller engine, you feel the instaneous acceleration.

I can't compare the "thrust" of the 951 to the Eclipse. The 951 has a hell of a lot more (the eclispe is stock 210hp). The 951 feels twice as fast.

That said, I hope the eclipse isnt that scary over 120mph. If it is, I will be adding some H&R springs (TUV approved). It cant be as bad as an Alpa 147 or a Ford Focus. The reason for buying the Eclipse was that I am shipping a car to Europe and the 951 would need half the parts put back to stock (everything from non-TUV approved wheels, brakes, suspension, engine modifications, etc) or get it approved for road use. The stock car is much easier and the Eclipse turbo was never sold in Europe so they just classify it and look over to see if they see any obnvious changes. Also, driving a 951 in the snow sucks (it might not be as bad with winter tires) but for all-weather, general daily driving the Eclipse should work.

-Dana

lee101315

I never said it was a horrible car. It just sucks to drive after I drive the 951

The DareDevil

Dude, I bought an '01 Jetta 2.slow for the winter. I mean, the Jetta sucks regardless of what car I drive before it... But after driving the 951... Shoot me...