Reliablity Issue Compromised If Modded? - Page 4 - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat
GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat

Go Back   GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat > GM Technical Discussion and Questions > Performance, Brainstorming & Tuning

Performance, Brainstorming & Tuning Talk about modifications, or anything else associated with performance enhancements. Have a new idea for performance/reliability? Post it here. No idea is stupid! (please use Detailing and Appearance for cosmetic ideas)

LinkBack Thread Tools Search this Thread
Old 12-26-2006, 03:21 AM   #31
Senior Member
True Car Nut
Join Date: Jun 2004
Location: Glendale, AZ
Posts: 3,459
Thanks: 0
Thanked 1 Time in 1 Post
big_news_1 is on a distinguished road

To explain Mike'* comments a little more, normally aspirated motors are more susceptible to the effects of low air density. If you take a look at fighter planes from World War Two, you see the addition of various power-adders to planes as the war progresses. Aircraft developers started seeing the benefit of supercharging and turbocharging in order to make engines perform better at high altitude. A forced induction setup will not feel the effects of thin air as readily as an NA motor, for the simple reason that air is being compressed and blasted into the intake manifold. The L36, much like the earlier fighters of WWII, is normally aspirated, and is completely at the mercy of atmospheric conditions. Cool, dry air is more dense than warm, moist air. If you start tuning your car to the ragged edge for certain conditions, you'll notice it feeling weaker on days that have thinner air. That'* why Mike is saying he had to re-tune from season to season. Winter air is colder and almost always drier than summer air, and a maxed-out tune in the winter will often involve different fueling than a maxed-out tune in the summer. From the factory, our cars are designed to adapt to a plethora of different conditions and air densities, but when you start adding parts and modifying the PCM code, you affect the car'* ability to "roll with the punches."

I have certainly noticed the effects of seasonal change in my car. The temperature variation alone accounts for a lot of it. But I think Mike is right in saying that it'* more noticeable in a modified car than a stocker. It'* nothing to be worried about, either. I had my car dyno tuned in humid, 65 degree weather in Ohio, and then I promptly moved to Arizona where the word "humidity" is a foreign language and 65 degrees is enough to make you wear your winter parka. I simply babied the car in the heat of the desert summer, and I'm now enjoying the power that comes with the dry, cool air of the desert winter. You don't have to re-tune for the seasons, but you'll notice that changing conditions will have an effect on the butt dyno.

1997 SE w/SLE package
"White curse? I think it'* more like.... WHITE FURY!" - MyLittleBlackBird
big_news_1 is offline   Reply With Quote
Old 12-26-2006, 06:44 PM   #32
Senior Member
Certified GM nut
Join Date: May 2005
Location: Wickliffe, Ohio
Posts: 2,155
Thanks: 0
Thanked 0 Times in 0 Posts
McGrath is on a distinguished road

I would like to add something to this thread if I could. Here is a quote from Rogue
Originally Posted by Rogue
Anytime you raise valve lift and increase rpms you should put stronger springs in the car. ~130 dollars is pretty cheap insurance to protect against valve float or dropping a valve into your cylinder.
I myself would not feel comfortable if I put rockers in, kept stock springs even if I was not spining the motor faster.

McGrath is offline   Reply With Quote
Old 12-26-2006, 07:56 PM   #33
Junior Member
Posts like a Ricer Type-R
Join Date: Aug 2002
Posts: 11
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road

I agree 100% Ed. I'm in that boat. I've got valve float. And I'm fixing it soon. With springs.
willwren is offline   Reply With Quote

Similar Threads
Thread Thread Starter Forum Replies Last Post
1999+ Chevy Truck Reliablity Hans Lounge 6 06-19-2007 05:12 PM
Youngest Modded Bonne owner BonEvilSSEi Lounge 47 12-05-2005 03:16 PM
modded bonnevilles give me your lists!!! ly41181 General GM Chat 12 11-20-2002 10:57 PM

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 11:29 AM.