Nuked

iTrader: (9)

I have run 28psi spike tapering too 21psi at redline. Normally I run 26psi to 21at redline daily. I did run it at the 28psi setting for quite awhile due to a faulty gauge. No knock and 4* timing at peak boost. This is on everything stock other then flash, exhaust and intake filter. If I had a good fmic, I would def run 28daily and push the timing some more. pretty sure it would take it fine. From what I have seen, the best power comes from higher boost with conservative timing and a nice afr (11.2-11.5).

SQ

Dnealy

iTrader: (1)

Go back and read david's post today. It was on 93 octane, no meth and no c16. The car he was tuning had just got a complete build and the pump gas number where something rediculus like 533 or something.

l2r99gst

iTrader: (2)

I think TTP was referring more to the stock turbo'd car, not the 35R. Running that psi on pump gas on the 35R car makes sense. On the stock turbo car, it doesn't. All you have to do is look at a compressor map to understand that.


Eric

l2r99gst

iTrader: (2)

Honestly, that doesn't tell us anything. A car can run for a while without a perfect tune. I think we all know that here. How much mileage is that? What do the tod bearings look like? How about turbo shaft play? What is the difference in power numbers from 25 psi to 30 psi?

Hell, I have been running 22psi with cams for over a year now on a stock VIII pump. I guess that means that I should never install the IX pump I have?

Believe me, I'm not trying to be an *** here. All I am saying is that running that kind of boost on a stock turbo is pretty pointless, especially on pump gas. The outlet temps at the turbo would be ridiculous and the amount of timing that would have to be pulled compared to a lower boost level would rob power. Sure, a bigger FMIC would help a bit, but running a turbo that far out of it's efficiency just doesn't make much sense. And as I mentioned before, that 30-32 psi would be there for a blink of an eye. That boost curve would look just silly, tapering faster than I don't know what. Of course, that is the stock turbo is screaming to the tuner to let him know that it doesn't like that, but anyway.

The original car with the HTA35R, race motor, etc....now that is a whole different story and that makes sense.


Eric

mifesto

iTrader: (58)

i run 23 psi and tapers to 22. i have full boltons including fmic (no turbo upgrade or meth inj)

MalibuJack

iTrader: (5)

Its interesting, Every so often I raise the boost, and keep raising it, I've always ran conservative timing and had really good results on pump gas. Only when I would try to tell people about this 2 years ago, it was dismissed.

Cylinder pressure is the name of the game, it produces torque when it builds, but its always a balance between boost and timing as you have so many factors to take into account.

So far my experience has been to run higher boost and lower timing, as that netted more gains than higher timing with lower boost (which was how I used to tune my stock evo 8 turbo because it was just out of its efficiency range to run more boost)

I am really curious about actual hard numbers and differences between a standard "Buschur Spec" GT35r and the HTA35r I've seen amazing numbers, but I want to be certain that it is as big a gain as we're all hoping as I'm already producing the numbers I want on pump 93 octane, I can only imagine what I will get with E85 when I finally finish my move.

Nuked

iTrader: (9)

And lets not forget that with the 9, adjusting the MIVEC settings can affect the cylinder pressures and VE of the engine.

SQ

saiyanzzrage

iTrader: (11)

69

SixOneNine

iTrader: (19)

21-22

l2r99gst

iTrader: (2)

Exactly my point. I've known for years that running more boost and less timing will produce the best power, given that your turbo will be efficient at that boost level. We've had threads asking this questions years ago on the DSMLink boards and time and time again, bigger turbos performed much better at higher boost levels and lower timing compared to moderate boost and more timing, even on pump gas. I even remember a couple of threads in this forum over the last couple years asking this and we both stated this.

It's the point that DB stated about running 30-32 psi on the stock turbo on pump gas that I am disagreeing with.


Eric

EVO8LTW

iTrader: (41)

I wouldn't go down the road of turning up the boost and turning down the timing without monitoring EGTs along the way. Also, "zero knock" in an isolated WOT 3rd gear pull or two, especially on a non-load-bearing dyno, doesn't mean that the tune is "safe" for all conditions, especially long pulls in 4th and 5th gear on a warm summer day.

In any case, pushing a tune to the edge of the knock limit is silly IMO. If you really want more power, then do it right and make the appropriate modifications for the power level you want. If what you want is bragging rights for the internet, then go to it by doing a special tune for one day on the dyno or at the strip, but don't try to run the same boost/tune on a daily basis under all conditions.

EvoBroMA

EGTs and heat soak are the biggest concern to someone who is pushing crazy amounts of boost. its just overworking the turbo. and pointless when you can get the similar and more consistent power at lower boost, and more timing. If you keep on pushing hot air, you're gonna melt something.


at the same time though, many of us could run this daily because we don't push our cars that hard, and the gains in the mid-range are completely worth it.

jcsbanks

Now the temperatures are getting lower (<10C), I've turned up my AVC-R target to 1.80kg/cm^2 (up to 5000 RPM - 1.70 at 6000, 1.40 at 7500) with peaks up to 1.90. 99 RON, 30 degrees MIVEC advance, knock sums 3 or less, 11.5 AFR, 3 or 4 degrees ignition timing at 4000 RPM. It will take this with repeated throttle use in any gear - inlet manifold air temp stays under 25C because there is lots of airflow through the (stock) intercooler at speed.

In our summers (20-27C) I leave the midrange target at 1.7 up to 6000 RPM because I have to start pulling timing excessively. As long as the car is moving at speed the inlet manifold temps won't go over 35-40C.

dudical26

iTrader: (17)

I have noticed the same thing, the cold weather has REALLY allowed me to run more boost. It run 25psi more easily in this weather than it would run 23 just a couple months ago.

TouringBubble

iTrader: (2)

I see higher boost in cooler weather, but also more knock. I tuned the car for 25 psi in 90º+ weather and was running knock free. When the cold air came i started to get some big knock counts.