Your car is "kind of" unique. Remember, HiBoost is NOT using FULL ECU tuning on your car. They have supplied you with an injector controller. As we discussed at our dyno day, you are running STOCK spark values, originally intended for a naturally aspirated car, not a turbocharged car. This is a risky way to operate, but since you have a J&S, you are OK. Running on the dyno in different gears will usually show different loads. The different loads have different spark values and that is part of the reason why you have bumpier graph lines when you compare them. "Most" ECUs will have smaller spark values as the load goes up, though.MrTea said:in regards to gearing, and feel free to ignore it if i should only be talking about smoothing. but in my atx (where there is never anything really near 1:1) the higher the gear, the "bumpier" the graph gets. this was even at the dyno day where a quick 2nd gear pull happened to be on with my final pull. seen it on a few dyno's now. this would mostly me do the fact, if what i'm reading is correct and it sounds that way, since it takes longer to go through the revs you see a bit more variance....more chance to show those small variances? the #'s tend to not vary that much, but the look of the graph does....am i understanding that part correctly?
A J&S Safeguard is a very sophisticated knock sensor. It keeps an eye on detonation and allows you to run more aggressive settings without worrying about your engine exploding. Very helpful for a turbo engine if you're not 100% trusting of your tuning.smokethebear said:What's J&S??
No idea. The shop only had it working for a few weeks. I was asking Walter about Dynocom earlier because the shop owner mentioned that he was involved with the company.FocusSportVP said:^^^^ Well, lets see how the different levels of smoothing apply to this Dynocom then, if they have that feature. Please post up.![]()
In said case, I'd say the J&S was more primary than tertiary. There was NO ECU tuning provided, only fuel injector control. We're talking stock spark tables with low boost and enough fuel and the J&S to keep it from letting go. Personally, I don't like the way the J&S is being utilized, but I'm biased and much prefer full ECU tuning.Oreo said:My understanding is that J&S is a secondary, or in his case, terciary electronic control mechanism specifically designed to prevent premature detonation. It's usually used with FI to prevent blowing your engine.
belacyrf said:Here's the skinny as I understand it.
Dynoing in 4th gear is the preferred method, as 4th gear is the closest to a 1:1 ratio. Now with that said here are the plusses and minus to each as far as I know..
4th gear
- Should also provide HIGHER HP numbers than running in a lower gear.
- Better engine VE due to going through the RPM's slower, which means the valves stay open longer.
- Less parasitic losses from gearing due to going through the RPM's slower
- More heat generated, great chance for engine damange with sustained load.
- More time to conduct the run (if your doing a dyno day, 4th just takes longer)
3rd gear
- Worse engine VE due to going through the RPM's quicker.
- Greater parasitic losses from gearing due to going through RPM quicker
- Better Gearing multiplication for torque (but could still be lower thanks to the losses mentioned above)
- Less Heat built up during shorter runs, less danger.
- Dyno runs can be done quicker
The end result is, it doesn't matter as long as it's the same for each subsequent run, and that it's documented when you share your dyno so others are aware of the conditions.
Since it would take longer to make a sweep in 4th gear vs. 3rd, you may show an increase from not wasting power to accelerate the engine as much. I forget which model dyno it is that can have sweep time set (i.e. 7 second pull versus 15 second pull), but the 15 second pull shows more power, theoretically because of less waste accelerating the crankshaft, rods and pistons, etc.OrangeSVT03 said:Ok... this is sorta off topic but its still a descent question..
So if you "normally" dyno in 3rd as I do, then you do a run in 4th on the same dyno and the same day... would you make more power due to the valves being open longer/ better V E???
So does that mean that if a turbo'd car for example has full ECU tuning, you dont think a J&S is necessary? Or would it still be a worthwhile precaution?FocusSportVP said:In said case, I'd say the J&S was more primary than tertiary. There was NO ECU tuning provided, only fuel injector control. We're talking stock spark tables with low boost and enough fuel and the J&S to keep it from letting go. Personally, I don't like the way the J&S is being utilized, but I'm biased and much prefer full ECU tuning.
Necessary? No, but that is my opinion and there are plenty who disagree with me on that. Its a great product and I don't think there are any negatives other than its not free.tallguy2.3 said:So does that mean that if a turbo'd car for example has full ECU tuning, you dont think a J&S is necessary? Or would it still be a worthwhile precaution?
Hey, Tea; how ya doin'... I had responded to your question (or statement):MrTea
one other question back on topic, and it might not batter much. but from my understanding, ideas on dyno's have changed alot, though software has made up for much of it. but though the "gearing" might be 1:1 on the tranny, there are still numerous gears that it goes through before hitting the axle. back in the day, there was pretty much a true 1:1 gear where it was almost a direct drive. so though there is a 1:1 gear, it's not making all effort from the engine go straight to the axle/wheel.
...thought on this?
...with that last post of mine but had failed to include the "final drive" ratio; in my case, a 3.73:1.MrTea
...in my atx (where there is never anything really near 1:1)
Bump and to answer this question I missed:thekrux said:man i love this comeback. i gotta remember to blame my friend next time i need an internet scapegoat. :lol:anyway what do the sae din eec stand for?
I believe it is European Economic Community...FocusSportVP said:EEC = I don't recall the exact wording but its a European standardization IIRC.