441 cid dyno results

[Paul Workman]

For easier viewing...



IMMMMMMMpressive!!

Excluding inertia and drivetrain losses, that would put it comfortably north of 660 hp at the crank...an enviable figure for any NA, street driven Corvette!

I couldn't help but notice, there is quite a bump in torque between the two runs - or so it seems ( a little hard to see the graph), resulting in a pretty good lift in HP across the spectrum. Can you shed some light on what made the difference in the runs? Were they done on the same day, or is one an overlay from a previous test?

P.

[ALZR1]

Paul the torque/HP difference between the two runs is the cool down time I would think.
Wow Kevin very impressive out of An automatic N/A Z.
Good Job Pete,you know those 247 are starting to look really good.



AL.

[FU]

Nice Kevin . And with an automatic too !

[kcl98]

Thanks Frank.

[XfireZ51]

Originally Posted by ALZR1

Paul the torque/HP difference between the two runs is the cool down time I would think.
Wow Kevin very impressive out of An automatic N/A Z.
Good Job Pete,you know those 247 are starting to look really good.



AL.

Al,

I'm assuming the 247 is the intake cam duration?

[ALZR1]

Originally Posted by XfireZ51

Al,

I'm assuming the 247 is the intake cam duration?

Yes Sir.
Back to Kevin good job.
AL.

[Pete]

Originally Posted by XfireZ51

Al,

I'm assuming the 247 is the intake cam duration?

Thanks Al
For the non believers exhaust cams are basicly Stage I.
This car starts and drives like grandmas Oldsmobile
Kevin drives this car to and from work 30 miles each way in traffic.

Pete

[Paul Workman]

Originally Posted by Pete

Thanks Al
For the non believers exhaust cams are basicly Stage I.
This car starts and drives like grandmas Oldsmobile
Kevin drives this car to and from work 30 miles each way in traffic.

Pete

In support of your post, or more correctly, your point that a big inch LT5 making huge power does NOT suffer for street manners and low end torque or drivability...Excellent job, Pete.

See link

P.

[XfireZ51]

Originally Posted by Pete

Thanks Al
For the non believers exhaust cams are basicly Stage I.
This car starts and drives like grandmas Oldsmobile
Kevin drives this car to and from work 30 miles each way in traffic.

Pete

Pete,

I think we have gotten a number of data points lately that suggest exhaust isn't the issue. In fact, on a stock block, intake cam may not be the constraint. We've got some pretty good numbers for stock cam stock displacement motors putting out between 430-450rwhp. I had a converstaion with FU at BG and he stated that the LT-5 was actually overcammed. I'm beginning to believe that's pretty accurate. The motor appears to have been "throttled" from the factory. Just look at the performance bump you get by simply porting the top end. This baby just needs to breathe more.

[kcl98]

Originally Posted by Paul Workman

For easier viewing...

IMMMMMMMpressive!!

Excluding inertia and drivetrain losses, that would put it comfortably north of 660 hp at the crank...an enviable figure for any NA, street driven Corvette!

I couldn't help but notice, there is quite a bump in torque between the two runs - or so it seems ( a little hard to see the graph), resulting in a pretty good lift in HP across the spectrum. Can you shed some light on what made the difference in the runs? Were they done on the same day, or is one an overlay from a previous test?

P.

Paul - Al is correct - the difference in the two runs is simply cool down time - amazing. Also a testament to how vulnerable the cars are to heat soak - at least the big inch ones. I think this helps explain why the car was able to "pop" a 10.44 @ 133 after running a pair of 10.5-10.6 @ 131.5 - the cool down really does matter that much - and these dyno results prove it.

Kev