Yeah, I know #770 not a bracket racer, and is more a touring sporting VS sports, but the motor feels decent I wanted to see where I was in 0-60 times.

I gave it a shot today with one of those apps., did a few runs, and came up with an average of 8.2 seconds. Anyone know what the original 912E was? I've seen 11.5 to 9.5.

On the redline, I haven't spun the motor into the red, but shift JUST at the leading edge. I havent taken to the dyno yet, will probably do eventually, but want to go schmooze the guys a bit and get to know them before I feel comfortable putting the car in someones hands.

I'm surprised at how strong it feels and is still pulling strong even from 5000-5600RPM. Has enough torque at lower (under 2200) but engine wakes up from 2400-5500. I haven't spun the motor faster than that, but it pulls very fast to redline in first and second, third is a bit longer but then are close to 90 so I back off. I'm sure a pro can get more out of the motor, this is just the first setup, but I'm really surprised and happy at this point.

With the Heads being redone by Hoffman, a cam profile of 287 DUR. X .430" LIFT, solid lifters, swivel foot adjusters, balanced crank and KB pistons/etc, and Pertronix ignition, what or how can I figure a realistic NEW redline? I'd like to take it to 6K, but don't want to be stupid.

I'm asking because the motor feels like it wants to keep pulling.

What valve springs?

Talk to Lynn. Sounds like your motor was built right and definitely higher than stock redline.

No Idea, whatever Len Hoffman uses when he rebuilds heads. I'll have to ask him.

in what gear did you hit 60? 3rd?

Yep, it's what valve springs determines the Red line. I had Jake put HD ones in so I can spin upto 6500rpms without valve float.
Stock springs new are good to 5800-6000rpms then float as you can feel it and the engine has no more power.

"Redline" has little to do with springs. It has to do with connecting rod ratio. The point where down force turns into mass and causes self destruction. It's math. Every engine has a formula.

it has to do with valve springs if you dont have good ones...
Are you talking about piston speed though?

http://www.strokerengine.com/RodStroke.html


It is a function of the rotating mass. I did a custom engine for a BMW 2002. The stock connecting rod ratio is 1.6875. Drop the 1 and the decimal point, the optimal RPM range for this engine is 6875 RPM's. If you push the engine 0ver 7k on an extended run the crank speed combined with the swing of the crank exceed the ability of the piston to keep up. It becomes an opposite force and the rod fails at the wrist pin. I used a longer Audi connecting rod and a VW piston to bring the ration to 1.7.

Valve springs are not the source of the event. But they aid in allowing the engine to operate at the higher limits.

But it's more than that, Rick, what you're talking about is the theoretical max RPM for the rotating mass while red line is for the whole engine. If you're using weak stock springs that float at 6500 RPM's and they touch a piston you're just as done as if you'd had a wrist pin failure. The red line for the whole engine is limited by the weakest part, so in this example it's more like 6250 RPM's instead of 6875.