max octane for stock engine?
08-13-2011, 08:05 AM
#11
Thread Starter
ok so car is back it was mapped for a 50/50 mix of 93 octane and VP Racing 110 which is 107 octane.
It ended up at 222HP (dyno dynamics), previously on another dyno dynamics on 93 on it made the same 222HP!
But that same map with93/110 mix made 208HP for the first run on this new dyno.
So the original tune for 93: (stock ecu vs aem):
[attachment=7562:dyno-small.jpg]
The baseline with 93/107 mix:
[attachment=7560:carter-dyno1 (Large).jpg]
final tuned with 93/107 mix:
[attachment=7561:carter-dyno2 (Large).jpg]
I'm not realy sure why the baseline looks so whacked compared to the original pump gas tune?
Would the higher octane make it run rich? its very hot and humid here atm..
The tuner said he added a lot of timing, driving it around the car feels good, it seems very smooth in low rpms' and doesn't backfire and burble on the overrun like it used to
It ended up at 222HP (dyno dynamics), previously on another dyno dynamics on 93 on it made the same 222HP!
But that same map with93/110 mix made 208HP for the first run on this new dyno.
So the original tune for 93: (stock ecu vs aem):
[attachment=7562:dyno-small.jpg]
The baseline with 93/107 mix:
[attachment=7560:carter-dyno1 (Large).jpg]
final tuned with 93/107 mix:
[attachment=7561:carter-dyno2 (Large).jpg]
I'm not realy sure why the baseline looks so whacked compared to the original pump gas tune?
Would the higher octane make it run rich? its very hot and humid here atm..
The tuner said he added a lot of timing, driving it around the car feels good, it seems very smooth in low rpms' and doesn't backfire and burble on the overrun like it used to
08-18-2011, 02:52 AM
#13
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The leaded gas is gonna kill ur cat and O2 sensors! When the leaded fuel burns it creates a very thin film in the engine and also on the cat and O2 sensors not letting them do their jobs which if u want to keep ur car street legal is going to create emissions issues.
08-18-2011, 10:56 PM
#16
Registered User
higher octane = more complex molecules
What does this mean? The more complex the molecule, the harder it is to break down during combustion. To counter the slower burn rate of the fuel, you have to increase cylinder pressure. You accomplish this by ether boosting, increasing compression and/or advancing timing.
So it doesn't really "allow" you to run more timing. You HAVE to run more timing. If you didn't, you'd never reach MBT.
08-19-2011, 04:19 AM
#17
Thread Starter
Originally Posted by Mike21' timestamp='1313181409' post='20873065
higher octane = higher resistance to pinging.
It'll allow you to run more advanced timing.
It'll allow you to run more advanced timing.
higher octane = more complex molecules
What does this mean? The more complex the molecule, the harder it is to break down during combustion. To counter the slower burn rate of the fuel, you have to increase cylinder pressure. You accomplish this by ether boosting, increasing compression and/or advancing timing.
So it doesn't really "allow" you to run more timing. You HAVE to run more timing. If you didn't, you'd never reach MBT.
So is this what happenned with my dyno's? the 93 octane tune was maxxed out and made 222HP.
Then with the 110Mix that tune was rich and made 208 initially.
Then he added a bunch of timing and pulling it back to 222HP again? or was there some dyno error?
My gut tells me it did pickup at least a bit because its running heavy wheels, a bit extra weight and its hot and humid here and the car still feels strong.
I guess what I need to do is take it to a dynojet and swap out ECU's and fuels
08-19-2011, 04:34 AM
#18
Banned
with no tuning leaded gas will probably loose power, the fuel is different and will require different amounts of fuel to maintain proper afr.
I wouldnt run leaded gas unless you have to, but these motors can benefit from higher octane fuel
I wouldnt run leaded gas unless you have to, but these motors can benefit from higher octane fuel
08-19-2011, 08:30 AM
#19
According to documentation from Hondata and others, the engine will make more power on higher octane unleaded, but the gains are minimal and extremely cost prohibitive in the long run.