MAF drop after head swap????
Thread Starter
TECH Resident
iTrader: (1)
Joined: Dec 2001
Posts: 933
Likes: 0
From: Overland Park, KS, USA
MAF drop after head swap???? Before my 5.3L TEA head install, I was running approx. 41 lbs at 6400 rpm w/ just the cam. I thought I would see a gain w/ the head and LT setup...but now after getting the AF pretty close I am seeing mid to low 30's at the same RPM. Why is this? Is it because of the lower volume heads?
Any thoughts here are mucho appreciated.
<small>[ April 05, 2003, 11:45 PM: Message edited by: BLUEBYU ]</small>
Any thoughts here are mucho appreciated.
<small>[ April 05, 2003, 11:45 PM: Message edited by: BLUEBYU ]</small>
Re: MAF drop after head swap???? My heads and cam car showed a 16% increase in airflow through the MAF. Stock, the MAF flow was 263gms/sec. After heads and cam the MAF reports 305gms/sec. You should definitely see an increase in reported air moving across the sensor at the top of the gear shift. Perhaps check for airleaks?
Good luck,
Richard <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Good luck,
Richard <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Thread Starter
TECH Resident
iTrader: (1)
Joined: Dec 2001
Posts: 933
Likes: 0
From: Overland Park, KS, USA
Re: MAF drop after head swap???? I did not change the MAFS in any way. It is a Granitelli. If it is unmetered air the car would not run/respond like it is now. I think it is due to the head volume change...5.7L to 5.3L. I also may have been running rich prior to the head swap and did not realize it. My O2's were in the range of .93 and injector duty was around 75% at high rpm WOT. This would demand more air than if it were leaned out. I now have RMS "mail order" programming for a H/C setup and am showing O2's around .8 and injector duty about 65%. I am getting a fresh dyno tune w/Edit Monday by Raging Motorsports (btw, the new dyno rocks!!!) to eliminate my MAFT tuning of 6% lean. Am I on the right track here?
<small>[ April 06, 2003, 01:17 PM: Message edited by: BLUEBYU ]</small>
<small>[ April 06, 2003, 01:17 PM: Message edited by: BLUEBYU ]</small>
TECH Apprentice
Joined: Jun 2002
Posts: 355
Likes: 0
From: Earth
Re: MAF drop after head swap???? I have suspicions that the GMS, without a screen, does not deliver the correct readings.
That being said, I think getting LS1 edit tuning is the way to go. Please keep this thread updated with your results.
That being said, I think getting LS1 edit tuning is the way to go. Please keep this thread updated with your results.
Thread Starter
TECH Resident
iTrader: (1)
Joined: Dec 2001
Posts: 933
Likes: 0
From: Overland Park, KS, USA
Re: MAF drop after head swap???? Did you go with 5.7L heads? I would know if I had any air leaks....it wouldn't run as good as it is now. The car is strong and runs like a champ! No codes...no KR. Anybody else?
TIA
TIA
Trending Topics
TECH Apprentice
Joined: Jun 2002
Posts: 355
Likes: 0
From: Earth
Re: MAF drop after head swap???? Do you have a screen in the MAF? A friends car I tuned showed a max of 320 gm/s with -8 trims and after installing the stock maf the meter now reports 355 gm/s with the trims responding downward to -2.
Sounds like you must have un-metered air getting to the engine, especially if you are making more power than before.
Sounds like you must have un-metered air getting to the engine, especially if you are making more power than before.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
