11 replies to this topic

[VICHRIS]

I had a camaro owner recently tell me that the 5.7 hemi doesnt run well at higher altitudes as compared with fomoco and GM engines. I would guess that most any engine doesn't run as well at higher altitudes as it does at sea level.

Funny thing was was that after a huge list of performance mods to his SS camaro (he was bragging that his SS with the mods he's done will outrun the ZL1) he admitted to me that he still only runs 14's and he probably admitted it because a couple of his buddies were there to call him on it.. I ran low 14's last summer with nothing more than a CAI. I've since added a predator 91 oct CAI tune and SRT headers. We live at about a mile high. I invited him to the track so we could see just how badly my hemi runs at Altitude.............

Was he just blowing smoke or is there some truth to what he mentioned about hemi's and altitude?

[ironchallenger]

sounds like a CT question to me......

[Jay6spdRT]

I would imagine all naturally aspirated engines are similarly affected by increased altitude, in a proportional fashion. However, the computer's of some cars may be able to compensate slightly better than other cars, in adjusting spark and AFR accordingly. Might be a MAF vs MAP issue. Chevy and Ford use MAF I believe, whereas Dodge uses a MAP sensor for airflow. Not sure if there's any 'real world' difference in the way a MAF equipped vehicle performs at 5000-6000 ft altitude vs a MAP equipped car.

[VICHRIS]

"sounds like a CT question to me......"



Well I posted it there too.....and at least I got an answer......just sayin.....I have no problem with them.....nor do I have a problem here.....sounds like you do.



Jay6spdRT.....thank you sir for an intellegent responds. Never thought of the MAP vs MAF airflow sensor.

I even tried googling this and came up with nothing.

[ironchallenger]

we all have a problem with CT



isnt that why we're here ?

[70Barracuda]

I had a camaro owner recently tell me that the 5.7 hemi doesnt run well at higher altitudes as compared with fomoco and GM engines. I would guess that most any engine doesn't run as well at higher altitudes as it does at sea level.

Funny thing was was that after a huge list of performance mods to his SS camaro (he was bragging that his SS with the mods he's done will outrun the ZL1) he admitted to me that he still only runs 14's and he probably admitted it because a couple of his buddies were there to call him on it.. I ran low 14's last summer with nothing more than a CAI. I've since added a predator 91 oct CAI tune and SRT headers. We live at about a mile high. I invited him to the track so we could see just how badly my hemi runs at Altitude.............

Was he just blowing smoke or is there some truth to what he mentioned about hemi's and altitude?

Sounds like typical Chevy bravado speak to me, probably operating off of some Chevy rumor. For what it's worth I've never heard of this and I'd be leaning to the blowing smoke theory. Jay probably has the reasoning down for what the guy might be basing things on.

If you want to see how your cars numbers compare to those of us that run closer to sea level go ahead and plug your numbers into a DA calculator http://www.dragtimes...-calculator.php That might give you an idea as to how your car is running compared to others with similar mods. (or basically stock).

If the Camaro guy is running low 14's with his mods and so are you basically stock then I'd say the altitude isn't causing you any more problems than it is him. By the way Challenger RT's frequently beat Camaro's at the drag strip, despite what car mags may say.

[Jay6spdRT]

Speedy is the guru on MAP vs MAF. He might have some input on this. I know that MAF has tuning advantages vs MAP - MAF measures CFM more accurately. As to whether that equals a MAF equipped engine losing less of a percentage of horse power at 5000 ft altitude vs a MAP equipped engine, I don't know.

[RT_6Speed]

Doesn't seem to

[HemiSam]

Highly recommend spanking the smack talker at the track. Go home. Make your woman squeal and then have her rub your belly after you've consumed enough pizza and beer to choke a goat. I'm simple that way...



HemiSam

[BACNBLK]

Highly recommend spanking the smack talker at the track. Go home. Make your woman squeal and then have her rub your belly after you've consumed enough pizza and beer to choke a goat. I'm simple that way...



HemiSam

That right there is good advise.

Joe

[Boatman]

It's just a idiots opinion and not a informed one at that. How the engine flows the air it gets determines more than the altitude. Like Slamming Sammie said go spank him and show him who his Daddy is.

[VICHRIS]

we all have a problem with CT

isnt that why we're here ?

I know alot of people do but I really don't......I just like options...... ....have way more issues with "Z" than CT

Highly recommend spanking the smack talker at the track. Go home. Make your woman squeal and then have her rub your belly after you've consumed enough pizza and beer to choke a goat. I'm simple that way...



HemiSam

...... sounds like "sound" advice