has anyone dyno'd an le5 comparing 87 and 93?

 

Have you actually monitored your cars reaction to using different type of fuel with a scan gauge of some sort instead of how it "feels"? Bet you'd see the difference there.

 

I don't have a scan gauge. And I don't use 87

 

You said your car acts the same with 87 so you have used it before. Just because a car doesn't "feel" different doesn't mean it isn't acting different.

 

That's what was in it when I bought it and continued to use it until I was told 93 is better.

 

according to a couple people on hptuners, average 1/4 mile time for a bone stock 2.4 running 87 octane is 17.2

 

who ever told you that dont know ****. If you run a 17.2 give up driving. The auto 2.4 run high 15s and the 5 speeds run mid to low 15s.

look up car and driver fastest cars for under 20g cobalts 2.4 come in sec place.

 

I think he was trying to show how it would run using 87, not 93 with a good driver as your numbers require.

Personally, I watch kr all the time on my torque app, stock 2.4. On my 20 mile each way commute to work, i see up to 3 deg kr running 93. I ran 89 for a tank just to see the difference and saw up to 6 deg on the same commute until the tank was empty. Both fuels saw 0 kr doing hard pulls up to 6500 rpm, all kr was at part throttle settings. Wish I was watching timing advance for those pulls, would be nice to see how many more deg 93 allowed, cant be much as the butt dyno didnt seem much different. Next time.

 

I have my car up on the lift cutting the rotors. I noticed the down pipe has one cat in it. I just worked on an '08 Cobalt with a 2.2L and it had 2 cats. Is one federal and one california emissions? or did they add the second cat in '08?

also, the exhaust seems pretty unrestricted after the manifold to the tail pipe with the exception of the converter and resonator. Is the exhaust really that bad in these?

 

Only restriction is by the rear axle.


The difference in high and low octane WOT timing for a stock LE5 is 6-7*

 

I sucked at the drag strip.
I ran my car with just k&n sri with 93 and oem tires, the car was able to get 15.6 on the 1/4 mile
A better driver got 15.4 on my car
Now I can only get 14.4-14.6 on 1/4 mile.... The car have been able to keep up with tuned lnf from rolls. So the car have the power but I don't know how to use correctly or even launch the car

I don't think 87 will affect that much to get a 17sec on the quarter .

 

14.4-14.6 boosted right?

 

Catback being the same as lsj, no its not bad. The gains are in header/dp. Catback will hardly see any gains unless going above 300whp, as seen on the lsj cars.

 

My 08 2.4 had two cats. I'm in Canada, so it must be across the board.

 

Yes

 

I'm going to keep the stock cat back then. I don't want my Daily driver loud. I have my Corvette with Flowmaster 44s when I want to be obnoxious

 

Not on 87 octane it isnt lol the low octane table is set for 12* of ignition timing across the mid range and 17* of timing at the high end at WOT, you aint getting out of the 16's with that.

 

Qwank with a cat back and a K&N Short Ram I ran 14.9 at NED. as it was already said a header/dp would do you better for gains, and a tune would help. There are N/A 2.4s in the mid 14's. i was hoping to be the fastest 2.4 N/A on the board, but its not going to happen. not spending the $$ on a tune, my 1-2 syncro is starting to let me down, and with 190K miles, not sure i want to spend that kind of money.

i would fill it up on 93 and run this next tank very low. fill it up again, diconnect the battery for 10 minutes and let it relearn. should wake the car up a little bit. give it a few days, but it will feel better

 

Build a turbo kit. That'll help.

 

yeah I have an 1/8 of a tank left of 87 so I decided to wait until it's gone to fill with 93 so it wasn't mixed.



I have a 90% complete supercharger kit. So I'm going that route

 

running 93 and keeping the RPMs up definitely helped a lot. or maybe it was because I took the bong out of the right front fender the other day

 

Ive ran a 2.2 eco cavi 5spd with exhaust in my auto 2.4 and even with an exhaust leak and untuned I just slowly kept pulling away. Was about 2 cars by 80 if I remember right.

 

Haven't gone WOT and using regular gas. Lawlz.

 

this was months ago a few days after I bought the car, and I was comparing normal driving LE5 to normal driving L61. the powerband is definitely different in both engines.

 

Show it some love
Plugs, filters all the way around, maybe some tb cleaner, **** lik that. My 05 l61 winds out first and second like a chamo haha


And ive played highway games with 2 friends that got cavies, and for both of them te difference was the 5 speed up top vs my 4speed. But no real difference in power, all stock