What can I expect in a Dyno Tune?

[T0nyGTSt]

I always wondered whether this whole process should be checklisted like the SEVs/RAWs compliancing.

ie.

replace fuel filler neck - check

recplace tyres - check

Because what happens at a dyno tune at one workshop will not match another.

I wonder about a few things.

Like do you run with or without silencer?

Do you run 1.5bar high boost and is that fine for the whole boost range? ie. is that relevant if you run only 0.5 bar for everyday? Or is there one run for high and one for low?

Do you test for cold start? Idle performance with aircon?

I wonder if a checklist for the typical car here is warranted?

Typical being PowerFC, maybe mix in a z32, fuel pump, big turbo, EBC etc.

T.

[B33st]

would like to know too

[Steve]

Well I can tell you what I like to see.

First, change your plugs, even if they are only a few thousand kays old. If the car is out of tune, it is possible they are covered in carbosn and crap. Cost less than $20 a set. Make sure you have the right plugs before you take the car in.

Idle and cold start - if there are any issues you cannot sort yourself, let them know. If it is cold start,they may need the car overnight, so they can see what is happening when the car is cold.

Light throttle. Seems pretty obvious, but is often overlooked. It doesnt take a heap of time to check the AF ratios at 60, 80, 100, 120 kmh. This can save you a fortune in fuel, as the car can be tuned pretty close to stoich.

Next start tuning power. Usually they will do a prelimnary power run and check AF ratios and timing. Usually, tuning starts at lower boost, then increases as everything is checked safe at that level. Finally, it is worth while getting the tuner to do a final run at lower boost, after the high boost has been sorted, just to check that everything is still ok down low.

Perhaps some people like to do it different, but I have found that there arent alot of places that do their tuning as above, esp the part throttle/cruise work.

Spending a little more time on the dyno to make sure everything is set up right can make a hell of a difference to how the car handles on the road. It is always a good idea to let the dyno operator know you are just after a safe tune, which will ensure they dont push too hard, or tune right on the edge. Tuning too close to the edge can cause problems when you get a poor batch of fuel, change in weather, fouled plugs etc. so IMHO isnt realy worth the worry.

Remeber too, that dynos are a good way to make sure your car is running well, and a guide to guage what difference mods have made to power delivery. If you are after big numbers, just buy a 454 and throw a couple of T88s on it:p

[T0nyGTSt]

I would imagine that a final light road tune after the dyno tune would be good to follow up on the results?

T.

[Steve]

Well, as test on the road can be a good thing. Stuff like making sure the clutch takes up nice and smooth. I have a twin plate unsprung clutch, and adding a bit of fuel in just the right place makes a world of difference to the take up. Generally most of it can be done on a dyno by an experienced tuner. To get someone to do a full road tune (I did it once, took 2 days) is a very costly exercise, and debatable whether it is worth the extra.

The biggest difference IMHO is getting an experienced tuner, who takes the time needed to do the job right instead of rushing to try and make a quick buck.