gas mileage after cam install
Thread Starter
Le Mans Master
Joined: Aug 2005
Posts: 7,201
Likes: 0
From: DP(oh you know where) IL
St. Jude Donor '06
gas mileage after cam install
Just wondering what you guys are getting as far as gas mileage after your cam install. I'm looking for mild cam with headers and intake mods. Cams in the 228/228 to 234/236 range. Also, not what your DIC says, but what your actual mpg is. Thanks in advance
Drifting
Joined: Dec 2005
Posts: 1,720
Likes: 3
From: East Hampton CT
City mpg isn't accurate since conditions can vary so much. Highway mpg for me has been pretty consistent before and after my cam, I might have even picked up a few mpg with my 228/232. DIC shows 30-32 on flat ground or slight inclines. I average around 21-25mpg per TANK but I have at least 50% city (% of time, not miles) out of each tank so I consider that great. As a comparison, my wife's Pontiac Vibe 4cyl auto gets approx 28mpg under the same conditions with me driving.
FYI, towing a trailer with two cruiser motorcycles behind it avg'd 22.5mpg down and 24+ mpg back from CT to Fla. Gut feel, I would have been 32mpg+ without the trailer.
If you're worried about economy, don't...your mileage usually will increase with a better breathing engine (assuming a good tune).
FYI, towing a trailer with two cruiser motorcycles behind it avg'd 22.5mpg down and 24+ mpg back from CT to Fla. Gut feel, I would have been 32mpg+ without the trailer.
If you're worried about economy, don't...your mileage usually will increase with a better breathing engine (assuming a good tune).
Race Director
Joined: Jun 2004
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From: Schaumburg IL
CI 7-8-9-11 Veteran
St. Jude Donor '06-'10, '13
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Thread Starter
Le Mans Master
Joined: Aug 2005
Posts: 7,201
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From: DP(oh you know where) IL
St. Jude Donor '06
Thanks guys, i was just wondering because I am getting 13mpg around town with some highway. Could it be a dirty maf sensor and/or bad front o2s? The car runs great, but there is a strong gas smell at startup
Melting Slicks
Joined: Aug 1999
Posts: 3,452
Likes: 3
From: Spring, TX
I went with the somewhat mild cam in my sig. My milage actually improved due to the tune leaning out the air/fuel mixture. It idles at 850rpm and has a little lope in it with the 112 LSA. With the cam, intake, and exhaust the car went from 297 RWHP to 357 RWHP.
Drifting
Joined: Dec 2005
Posts: 1,720
Likes: 3
From: East Hampton CT
Sounds like you have a rich startup condition at best, which never helps fuel economy. Also, how long do you let it warm up? I let mine idle on avg for 30sec to a min and then start driving but I don't rev it up until the engine and oil are up to temp.
Thread Starter
Le Mans Master
Joined: Aug 2005
Posts: 7,201
Likes: 0
From: DP(oh you know where) IL
St. Jude Donor '06
Did the car EVER get good economy after the cam? If not, you need more tuning. If it has gotten worse, then I would definitely recommend cleaning your air filter, cleaning MAF, and checking for 02 codes and operation. Some tuners turn off the 02 codes that cams and headers can cause, so datalogging is your best bet to make sure they're functioning properly.
Sounds like you have a rich startup condition at best, which never helps fuel economy. Also, how long do you let it warm up? I let mine idle on avg for 30sec to a min and then start driving but I don't rev it up until the engine and oil are up to temp.
Sounds like you have a rich startup condition at best, which never helps fuel economy. Also, how long do you let it warm up? I let mine idle on avg for 30sec to a min and then start driving but I don't rev it up until the engine and oil are up to temp.
the bad gas mileage started as soon as i installed the cam. I used to get 17-18mpg around town with some highway. I thought the tune would help it. I let it sit for a min at most when i first start up. basically when the rpms settle down to 900 and then the idle will drop to 875 after a couple min. I also take it easy until the oil temps warm up for the springs.The car just hit 50k miles
Drifting
Joined: Dec 2005
Posts: 1,720
Likes: 3
From: East Hampton CT
Assuming this isn't because of a heavy foot because of the fun from the cam, I'd suggest checking the tune out further. Keep in mind that low rpm and throttle transitions are often the longest thing to tune and are critical for economy. Lots of tuners can put down a solid AFR and good hp/tq....but drivability and economy is harder to come by. Unless the tuner uses an eddy current load type dyno, they'll need to do a good amount of street tuning for optimal performance/economy. Even with the eddy current a good "check" on the street is important.
I have been developing my tuning hobby (I don't get paid so I call it a hobby) and I usually log my car and truck an average of a few times a month to either tweak settings or just monitor performance. It took me a while to nail down the various elements of a solid, consistent tune.
I have been developing my tuning hobby (I don't get paid so I call it a hobby) and I usually log my car and truck an average of a few times a month to either tweak settings or just monitor performance. It took me a while to nail down the various elements of a solid, consistent tune.
Former Vendor
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From: Tampa FL
St. Jude Donor '07-'08-'09-'10-'11-'12'-'13-'14-'15
Burning Brakes
Joined: Aug 2006
Posts: 956
Likes: 12
From: Eastern PA
I changed from the 2.73 to 3:42s, 2900 stall, new tranny, Trickflows 215s and a Comp Cam 232/238 114 LSA plus a host of other crap and mileage went from 30-31 on the hwy to 25-28 mpg dependent on hills and stuff. City driving- varies really I range anywhere between 15-18 mpg in the city. At soon to be $4.00 a gallon, I figured I will start selling plasma + sperm and possibly a kidney to keep my baby rolling.
Burning Brakes
Joined: Sep 2007
Posts: 832
Likes: 0
From: PSL FL
At soon to be $4.00 a gallon, I figured I will start selling plasma + sperm and possibly a kidney to keep my baby rolling.
[/QUOTE]
I am with you, "F"ing government needs to step in and fix the prices on fuel.
[/QUOTE]I am with you, "F"ing government needs to step in and fix the prices on fuel.
Drifting
Joined: Apr 2007
Posts: 1,337
Likes: 67
From: Las Vegas
My engine builder is installing a 248/258 668/656 on a 110 lsa in my LS7 based 440" stroker. Good thing this isn't going into my DD. Gas mileage will suck. I sure do love that lumpy/choppy idle though. 