[Stan]

...Poughkeepsie NY. About 2000 miles are on the lump plus the Stage 2 exhaust. I'll try to post results depending upon how they provide the data. Output plus A/F Ratios.

The dyno is a new Mustang over at Visions of Speed... http://www.visionsofspeed.net/

If you want to observe just drop me a PM....we're going to do it at about 6 PM Thursday. Mustangs tend to give lower numbers than Dynojets, but the main thing is that a given dyno is repeatable so that you can find more when there is more. The Mustang is a loading dyno which is the best kind on which to tune.

 

[James A]

Definately post the results!

 

[Ara]

I wish it was a dynojet as I am familiar with them. Anyone have a conversion for mustang->dynojet?

 

[Stan]

>>>I wish it was a dynojet as I am familiar with them. Anyone have a conversion for mustang->dynojet?<<<

There isn't one, it's not really possible to convert, exactly. And some folks setup their dynos differently and play with the correction factors. The main thing is repeatability so that gains can be found. More = better most of the time.

Personally I greatly prefer dynos such as the Mustang or the dynapak that can load a car...so that you can stay at one RPM and tune out a trouble spot for example. You can't do that with the Dynojet stuff. With those you just accelerate a heavy roller which cannot hold the car at any RPM.

 

[Ara]

Stan, I understand what you are saying. I think you missed my point. I was just stating my comfort with Dynojet results in comparisons. There are enough of them out there with conscientious operators and I have seen so many runs / results that I can get a good feel for how much power a car has by comparing to results of other cars.

Ara

PS what are you tuning?

 

[Stan]

>>>Stan, I understand what you are saying. I think you missed my point. I was just stating my comfort with Dynojet results in comparisons. There are enough of them out there with conscientious operators and I have seen so many runs / results that I can get a good feel for how much power a car has by comparing to results of other cars.<<<

Good points...there is no question that there are lots of dynojets out there, and lots of run data to compare. I like it when there is accompanying data such as AFRs and exact mod lists.

The place that I am going to is supposed to have some Celica GT-S data as well as modded and highly modded GT-S info so that can at least be compared.

>>>PS what are you tuning?<<<

Nothing, just getting a baseline. I'll have some 2zzge gurus on the net look over the resulting AFR data. They seem to know the motor pretty well by now and may be able to make suggestions or comments about what they have found works well for this motor and how this motor compares to the "base" Celica GT-S version. So that may give some food for thought. I know that some of them really like what Lotus did with the briefly higher rev limit for use during acceleration as well as how it stays in Lift as long as revs stay over 5800 once you enter Lift at 6200. So it's much easier to stay on the big cam going through the gears, something at which the Celicas, especially the earlier ones, had trouble doing. It seems like the Celica guys like to run a particular brand of plug-and-play engine management (Apexi)and often gain about 15-20 RWHP from this. I don't think this can be asily installed on our cars as we have a different harness and engine mgt. But likely our box can be retuned as it is EFI Technologies based. This Celica increase I mentioned is coming mostly from fuel and spark as opposed to hard parts swaps. The Elise is supposed to be 5-10 HP stronger than the Celica's 2ZZ so maybe there is that much less of a software gain for us. Some of the Celica guys disconnect the flapper valve thing in the airbox - I think we may have one of those too.

 

[Stan]

Here's an Elise Dynojet overlaid with Celica GT-S results....

 

[James A]

Thank you, so we have about a 13% drive train loss, high but certainly within a reasonable range.

 

[adamant]

Stan, yes please post your results, we are all eagerly awaiting the outcome
I guess I need to Dynojet mine when it arrives and is run in. I am hedging toward the 12lb exhaust that Shinoo is promoting. but I want to see some dyno info on that one too

 

[Stan]

I'll be able to post some results and stuff tomorrow...I just have some print out sheets. I've got some data....and some interesting results....gotta figure out how to scan this stuff.

One thing I found out is that the motor does *not* like to get heat soaked. It back off the timing a bunch and you lose about 10% oompth. I run into that in autocross where you have to wait in line with a hot motor with the hood closed. We did a run with lots of heat soak to get a sense of this factor. Interestingly, in that case the motor had peak torque and HP at the same RPM, 8000! The Stage 2 exhaust sounded very mean and nasty BTW.

 

[gotapex]

Interestingly, in that case the motor had peak torque and HP at the same RPM, 8000!

I didn't even know this was possible since HP = Torque * RPM / 5252. Bizarre.

Looking forward to those charts.

 

[Stan]

>>>I didn't even know this was possible since HP = Torque * RPM / 5252. Bizarre. <<<

Nah, not bizarre at all. With the same scales, charts should cross at 5252. But that doesn't mean the *peaks* happen at those revs. In this case both torque and HP peaked at 8000 Rs when heat soaked but with those peaks being at different numerical amounts from one another.

 

[zvezdah1]

Stan,
Please explain to a clueless non racer, what is heat soak??
Thanks
Chris

 

[Stan]

>>>Please explain to a clueless non racer, what is heat soak?? <<<

Heat soak is when everything around the engine gets very hot, hotter than when under normal on-the-roll conditions. If you run your Elise a bit and then stop and pop the engin/trunk lid you'll feel a blast of heat near the exhaust side of the motor. If you leave the car parked with the lid down things get heat soaked as the engine compartment air flow is reduced at that time and the heat soaks into areas of the things in there that don't normally get quite as hot. So for example things like the water temp rises above the steady state condition, air temp sensor warms up, etc. Turbo cars can experience a greater degree of heat soak, such as when the intercooler gets hot and needs time to cool down. Until it does, the air can't be cooled as well. Another example is when you are in heavy traffic and you can watch the temp gage go well over 200...when you get moving again you can watch it come right down to the 180s again. Suppose your intake manifold area gets extra hot...this will warm up the air entering the motor and encourages detonation which leads to the knock sensor being triggered and then the ECU pulling out some spark timing. When dynoing a car heat soak tends to be an issue since the car can effectively be going over 100 MPH under load but it's just siting there. They use fans but this it not as good as real airflow over the car. For example the side air vents are active when your drive the Elise but inactive when your dyno the car. For the heat soak run we did, the car sat about 5 minute or so after a dyno run with the engine cover closed.

 

[zvezdah1]

thks stan
Chris

 

[Evl]

Stan,
Please explain to a clueless non racer, what is heat soak??
Thanks
Chris

Just to add to stan's reply, for kicks sometime, after you park your car, turn the key back to the on position so that the gauges are on, but the engine isn't running, and watch the water temp. It will go up, not down.

There are a lot of parts of the engine that are hotter than water temp, and without water flowing though the engine and radiator, this heat will even itself out though the rest of the engine.

When I autox, I usually open the hood between runs to allow convection to cool things off more rapidly. This combined with running the electric fan for a minute or two to cool off the water in the radiator, gets the underhood temps down quite a bit when it is time for the next run.

 

[gotapex]

>>>I didn't even know this was possible since HP = Torque * RPM / 5252. Bizarre. <<<

Nah, not bizarre at all. With the same scales, charts should cross at 5252. But that doesn't mean the *peaks* happen at those revs. In this case both torque and HP peaked at 8000 Rs when heat soaked but with those peaks being at different numerical amounts from one another.

Ah, gotcha. Thanks. That's a pretty high torque peak, don't think I've seen that on a non-bike. Really looking forward to the charts.

 

[Randy Chase]

Interesting point about heat soak. To also add to it, colder air is better for power. When everything gets hot, the intake also gets hot and you are sucking hot air. Not good for power.

I wonder about spraying some specific parts of the engine with a water sprayer while waiting to take your runs. Some competitors in certain cars lay bags of ice on the intercooler or intake bits.

 

[YELOTUS]

Stan...good to see dyno testing>>>

will be doing the same at a Mustang Dyno (Eddie current set up)...I don't think heat soak will be a REAL big issue if fan set up sufficient...when doing any blown engine heat soak is a killer...on my Audi TT with a MTM set up (turbo pushing 21 psi with dual intercoolers) I do my best runs on 1st or 2nd attemps otherwise I am toast...3rd on see a ~25% drop in output...ICs etc just can not keep up with heat soak..even with misting the ICs

Great you will track results and will be interesting to see comparison between the two Mustang setups...

 

[Ruediger]

---
There are a lot of parts of the engine that are hotter than water temp, and without water flowing though the engine and radiator, this heat will even itself out though the rest of the engine.

When I autox, I usually open the hood between runs to allow convection to cool things off more rapidly. This combined with running the electric fan for a minute or two to cool off the water in the radiator, gets the underhood temps down quite a bit when it is time for the next run.

There are some Rover-Elises in Europe which got an additional electric water pump to circulate cooling water after engine shut down as long as the water -T -sensor keeps the fan working This also helps to avoid the famous HGF of that engine.
Many other cars have such feature, also the Toyota Elise ?