What kind of gains have been had on a stock 2016 ZO6 with just a tune only?
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What kind of gains have been had on a stock 2016 ZO6 with just a tune only?
horsepower and torque gains
mo powa
Ludicrous speed may happen.
You may turn plaid.
mo tarrrqq
Your killing me. :)Quote:
Originally Posted by typhoon186
Looking for quantifiable numbers.:pray:
We picked up quite a bit with minimal mods and tuning.
Pink = Stock Everything plus a Halltech CAI (10.80's @ 128)
Blue = Blackheart LT's, 93oct pump, Tune and Halltech CAI
Red = Blackheart LT's, 93oct pump, Tune, Halltech CAI and E68 (Flex Fuel) (10.22@135)
Later on we put a upper/lower pulleys on and he's been 9.72@143 in that trim. Had to put it back on gas only and was using MS109 on this pass due to fuel system not keeping up. This is a manual C7Z.
Attachment 64866
James
What boost where you at with the final combo?
Also, what was the final HP with the pullies
Power was 714.6whp. Boost on the dyno (in KY) was around 16psi however track passes at MIR was 19psi at top of 3rd and 4th gears (sea level and higher barometer plus ram effect of CAI).
Whats crazy is I had to manually hold throttle back through the middle peak tq areas and ramp the throttle back in after peak tq to keep rail pressure from tanking.
Was low fuel pressure tanking also or just high pressure on the E68 @ 700whp?
Injectors are too small and the weakest link is the low pressure side.Quote:
Originally Posted by Terry Burger
The injectors will drain the rails so the HPFP tries to keep up and ends up draining the low side. If you add a second low side pump kit you will be ok unless you make more power and the rails will still lose pressure as the injectors try to work between SOI and spark.
This will happen on E10 also if you make enough power.
That's why everyone uses meth.
Some say they are fine dropping from 2300+ down to 1000 or 900 psi as long as AFR is good, which I don't agree with.
Some say low side is ok dropping from 70 to 40 which I don't agree with.
Some say it's ok to command 12.5 and get 13 which I don't agree with.
The right way is to be able to obtain the results you command. Fuel, spark, and air. If someone lets a car roll with anything less they are doing a disservice to their customers and are half assing their work.
On injection pressure on the BMWs at least I'm comfortable down to around 800psi. But the injectors will technically work as low as 70psi I think. They have a huge IPW range as you can imagine to allow fuel pressures of 70-3000psi so relatively speaking they flow a ton. Enough for 700whp via 6 of them on straight E85 if your high pressure holds up. At the low pressure you run out of injection window though of course. Where we run in to problems first is with the low pressure. So we've made several upgrades to that side. Once resolved it raises the fueling ceiling a bit until the high pressure starts falling despite sufficient low pressure. Once it drops below 700-800psi when demanding 2000psi or whatever then we normally consider it at its limit. There is no good high pressure upgrade for that platform so at that point we have to resort to adding on port injection to supplement the factory direct injection.
Anyway if the situation is low pressure is holding well but high pressure is dropping. Then, it's simply a high pressure pump volume issue. So I get that. I was curious if this platform hits the low pressure limit first and it sounds like it does.
In terms of stretching the fuel system by running leaner with E85 I run the BMWs leaner in most cases. Like in the 13s at peak TQ and high 12s at peak HP. But that is a different platform so I'll defer to what you guys have found works well on the DI LT4.
sounds very similar.
Quote:
Originally Posted by Terry Burger
This was not the case with the one we recently tuned. This was not on E68 fuel either. The extra upper pulley combined with the 10% lower gave enough airflow increase to max the high side pump out through the middle RPM range (Peak TQ). The reason this is possible is two things. First the high side pump is mechanical not constant, so it can only pump so much volume per stroke. Second at lower RPM the duration potential the injector can spray significantly increases.Quote:
Originally Posted by Higgs Boson
Now what most are going to think is how come the low side pump didn't run out first? The answer is the total volume of fuel flow capacity at peak TQ wasn't exceeded. Remember the in tank pump is PWM electric so it's just flowing what it can anytime regardless of RPM. And while the high side pump couldn't keep up at 4500rpm, it still wasn't at a point that outflows the low side electric pump.
I want to also note that to verify this as peak TQ rolled over and cylinder airmass and cylinder fueling demands diminished the rail pressure came back up. It's plain as day with the rail pressure looking as if it's the inverse of torque. And we got to a point that the low side was starting to fall some in the upper RPM.
Sounds like that is indeed the case, you just found the limit and rode it to redline. ;-)Quote:
Originally Posted by LSxpwrdZ
What fuel?
So low pressure was solid but high pressure crashed? Makes sense. What was ethanol percentage and AFR?Quote:
Originally Posted by LSxpwrdZ
Yes we did. Made many many dyno pulls manipulating ETC Limit vs RPM to control boost/airflow to maintain fueling. Fuel was MS109. It may have had 10-15% ethanol left in the tank.Quote:
Originally Posted by Higgs Boson
Fuel was MS109 but we didn't drain the tank so ethanol was still reading 10-15% IIRC. On something like Q16 I could see headroom a little higher. MS109 has a mid 13 stoich value meaning it's gonna require more volume than something with a mid 14 stoich point. The fastest pass at the track was at Lambda 0.87. Couldn't run it any richer cause it wasn't there lol.Quote:
Originally Posted by Terry Burger
That's good info, thanks for sharing it man.Quote:
Originally Posted by LSxpwrdZ
If you don't mind, where did you end up with the ETC Limit in the 1000 to 3000 range? It's something I always wanted to do but don't have the time to try it. 30%? 50? 70?
I ended up with 50% in the table but logging showed various TPS positions depending on which PID you're looking at.