NZ951

You are using the too cars to prove 318WHP in the 3.6, Im using them both to prove it wont be.

Krokodil

No I am not.

I am using the physical acceleration of one car with known Tq (independent of car or engine type) to show how much Tq is required to accelerate a car of lesser mass at the same rate. This is a simple physics problem (with many assumptions on drag, shift points, etc.). Newtons 2nd Law is just that, a law.

I do not see how you have proved anything. You have only made a claim. Please explain your proof?

Nor have I proved anything for that matter. I have only calcuated what would be the required Tq match acceleration (and backed into HP). We really wont know anything until he puts the car on the dyno. My estimate is ~310 RWHP and ~ 265 RW lb-ft (the Tq is what is used for the calc and Hp will vary base on peak RPM that is currently unknown).

This all started with me taking a good natured poke at a buddy. I guess I now know why you are hidng behind the rock wall icon.

Cheers,

NZ951

Yes agreed, your logic because of all those factors like drag prove you are inaccurate. Yes, all I did was make a claim, with proof, once again, evidenced in the comments made by the OP. Clearly you think you are the big tool on campus, and dont like being proved wrong, which is fine, good luck

Im not hiding, im right here... not going anywhere

Krokodil

You have not proved jack squat. Neither of us has. I am only doing math and you are guessing based on some assumption/expectation of performance (from experience?).

I happy to be proven wrong. Really. And the dyno may or may not do this. The math is what it is.

Tool? Interesting that you have started name calling. I was just trying to have a debate.

Cheers,

Flat6 Innovations

The biggest difference this combo has proven to make in my experience has been added torque and torque / throttle response from a lower RPM. These engines respond very well to added stroke, but not as much as the same displacement increases that are created by larger bores.

Of course, there are no rules and every engine assumes the character of it's designer and builder and thats what makes it fun.

jrgordonsenior

Hope you're right Jake. I only want 280-285 whp but loads of torque. It felt really good off the corners on it's test day, I'll post the dyno results when completed in 2 weeks.....

NZ951

So true... "Horsepower sells cars, torque wins races"

My track car, the AE86 in the avatar only makes 175WHP (from a 1.6 though), but have to rev it to 9,500 to get much out of it!

Flat6 Innovations

Road Racing is about getting off the corners more than anything else. Many times I have upped torque, or moved torque around within the RPM range and have gone faster, even when some of those changes made less peak HP. Throttle response is key to getting off the corners which always increases trap speeds on the straights following those corners. Having a super responsive, predictable engine is what separates the men for them boys.

If I see a peak HP gain, I also demand that that gain increase the average power under the curve all the way up to peak, else I don't consider a change to be a success. I also want to see a torque increase across the board.

Too many people over rate HP and don't understand that it is merely a formula that uses TORQUE and RPM to be calculated. Without TORQUE, HP Can't exist.

If I hand someone a dyno graph and I see their eyes wander to the peak HP number, I immediately shake my head and know that I am wasting my time dealing with them.

I think you will see positive benefits on the track from this, because these cars are heavy and their gearing also demands torque. Just remember, the 3.6 cranks are the weakest of the bunch. I hope you had it magna fluxed :-) (I even magna flux brand new Porsche cranks!)

jrgordonsenior

Yes crank was magna fluxed, knife edged, and polished.

BTW my plan for restricting in the unlikey event I do have 300or more rwhp is to use a Boxster 2.5 throttle body which as you know steps or tunnels inward. I've never measured and compared the inner diameters so I don't know how much of a restriction it is actually is, but significant I'm sure.....

NZ951

You would ideally want the flattest curve possible and limiting RPM would enable you to stay under the power limit? (and extend engine life )

logray

Awwwww man, where are the pics! I hope it's not too late!!!!

jrgordonsenior

Dyno'd this weekend at 302 rwhp with 285 lbs. of torque so my geeky Cayman friend was correct (or damn close). i restricted the intake with duct tape until we got it down to 292 rwhp which is where it will stay for the year. I won't have the torque numbers for the lower, restricted settings for a few days as his printer went down at the end of the day but I don't think it was significantly less.....

This was on a Dyno Dynamics 4500, on a Dyno Jet it would be higher....

NZ951

16WHP and 20lbs of torque off. Could be worse lol

Good strong numbers you got there!

Krokodil

If you are taking a shot a me, have at it, but the calculations were correct.

The Dyno at the track was about 5% off of Dynojet used as the baseline (we tested my car too so we have the reference). So, if adjusted for testing delta the math was nearly dead on (302*1.05=317).

There were a couple of other cars that we know about what they should make (other 3.8s) and they came in right where they should (340 unrestricted, so 340*1.05= 357 and equal to my engine)

We jokingly estimated 310 just to throw in some fudge factor for assumptions, etc. Considering the power bands are a bit different and RPM used were estimate I am very surprised it was that close.

JR, is that 285 right? If so, and the 302 is right, is says the engine is making peak HP at 5560 RPM, which seems low. Please take a look at the chart again and verify the axis.

In the end we made the necessary adjustments to HP and weight of various cars and had some great racing. On Sunday, positions 1,2,3 in GT3 (where we run) came across the line nose to tail (maybe closer) after 15 laps. Other than one questionable pass attempt/alleged door close in T1 the racing was quite pleasant ;-) We can look at the video from my rear facing camera and discuss.

Cheers,

logray

Those are some pretty impressive numbers, but I bet mine are going to be higher!