Dyno load + boost creep question
 

I'd like to make a couple of runs on the dyno with my FC in the coming weeks and have one pretty important question...

Like many forum members, I do have some boost creep to deal with on my car, even with a ported wastegate (which obviously wasn't ported enough). In third gear on the road the car makes a solid 12 psi which is perfect for the fuel/ECU I'm using (720 secondaries, Rtek 1.7 ECU).

My question is, will a dynojet put more/less load on the car during a pull or is it very consistent with the load of road-driving. I'm just concerned that increased load from a dyno may cause additional boost creep and I defintely don't want to overboost the motor during a pull.

My boost gauge does have a warning feature so I assume I can set it to maybe 13 psi and tell the operator to back off during a pull if the warning comes on.

I think some dyno shops(maybe all) allow you to do the pull while they run the dyno....

Mainly, I'm curious as to other forum members experience w/ boost creep on the dyno. Is it the same as, better than or worse than it is on the street. I always thought those big heavy rollers would present more load.

bumpity

I'd asssume to see around 230-250 rwhp with 12-13psi on my mods - seem like the right ballpark? Mods are in my sig.

Inertia type dynos seems to load the car less than the street. Eddy current, Mustang type dynos apply a more 'realistic' load...

What are you using to control your boost right now?

If you are using something what happens if you connect the compressor straight to your wastegate acctuator? How much boost?

James

DynoJet typically loads the car less.
Just run the car in 3rd - it should be fine.
Some will argue you NEED to do it in 4th gear, since that is 1:1 ratio and claim this has the least friction through the drivetrain.
They are right and wrong - it doesn't matter.
Just remember to keep your runs consistent in the same gear, and then you can do direct comparisons of the graphs.
If you do change gear, note that - the numbers will be different.

I like to do runs in 3rd gear, cause the car is under load for a less amount of time.
Trying to get the car to cool down in between runs is a pain in the ass sometimes.
4th gear pulls just take too long and heats the car up unnecessarily.


-Ted

Thanks Ted...