MSefi.com read only forum (Jan.15,2018)

i am going to be swapping out my 347 for a stroked windsor, and need to seat the rings immediately after cam breakin. i generally do this with wot applications to medium rpms and decelerate to idle and repeat many times while increasing rpms about 100 or so till i hit redline.

the power curve of the two engines will be completely different, so basically i need a tuned engine without tuning it.

the best way i can think of to do this is to build both engines in an engine simulator and find the % difference in ve and apply that to the fuel map.

What do you think, will that work?

any chance you could start it with a carburetor first to get it broken in?

no 4 bbl intake, no 2 bbl carb. the fuel supply also will be troublesome

I don't think it will work very well to just adjust VE % based on simulated environment. My opinion is that anytime things are modelled and theorhetical, the real world always always throws curve balls. A new build at WOT is playing for keeps.

For my new build... I spent a half day figuring out EXACTLY where my distributor rotor should be positioned based on comparable motors, sensor placement, and other variables. First crank of the starter, a ball of flame shot out the top, dyno guy said it's a bit too retarded, adjusted it a whisker, then fired it up.

Take my opinion for what it's worth, but if you spent a meaningful amount of $ on a new build take it to a dyno shop for break in with a carb. For several reasons....

- small expense compared to how much a new build costs.
- good dyno shop will have a shop carb to use for break in, and if you need an intake also to break in with carb they might have one, otherwise buy a cheap stock intake for break in with carb.
- most dyno operators are cool guys and willing to share knowledge which is good value in itself.
- get true power numbers for your motor.
- get an exact optimum timing number for your WOT pull, and if you have time, get optimum timing numbers for different levels of vacuum, and or RPM.
- dyno operators do 1-2 motors every single day and can diagnose a problem before you know there is even problem.

i think my last dyno day was $225, more fun than an amusement park, a cheap insurance policy, and more info than a semester at college.

at the very least.... if you decide to break in with MS.... build up your tune where you are certain that when you go WOT, things are in order. don't go WOT based on a theorhetical simulation.

Great post, TheMonkey. I agree whole-heartedly.

When I took my Corvette to the chassis dyno expecting to just get a tune, I left with MUCH more. They had barely even used Megasquirt, but were able to find and diagnose several problems just based on having an extensive knowledge of EFI systems.

They also were able to diagnose that my engine had never been spin balanced........ oops. Out it came. When they tore it down, there were 2 rod bearings ready to spin, and several main bearings trashed.

Had I not taken it to the chassis dyno that day, I'd have found this all out on the side of the road the hard way.

Take it to a dyno, be it engine or chassis and have them break it in, you'll be glad you did.