i'm doing a lt1 cam swap along with an manifold (7525) swap soon on my L05. there might be clearance issues with my EGR valve on the new manifold and my throttle body. so i was curious about what was the least duration needed to safely delete the EGR system. i searched but could not find it. btw, i will have EGR deleted on a new chip if i choose this route.

the cam is from a F-body LT1, duration 205*/207*

im thinking i should be able to squeeze by, but wanted to ask here first. there was one post on another forum stating anything greater than 204* on the intake was good enough self-EGR, and a few guys have already said i should be fine, but wanted to double-check and make sure that was correct. thanks guys!

-Blake

 

enuf duration to delete the EGR...huh?

If you have a chip with the EGR turned off then don't worry about it.

 

with enough duration in a cam, there really isnt a need for EGR, but i cant seem to find out what is enough.

arent there mileage issues from cams without enough duration without an EGR system?

 

no

 

No, just power isues.

Buy the way, the LT1 cam has a large lobe center angle that cancels some of the overlap effect.

 

so i should be fine with an egr delete? sorry, im still kinda new to some of this stuff...

:hail:

 

Usually when you delete the EGR you want to up the LSA to compensate for no forced EGR; by creating a natural EGR effect. Usually helps to increase driveability and gas mileage too.

 

Yeap, you will be fine as long as you remove it from the chip as well.

 

if you want natural egr effect, reuse the stock timign set. The factory has 5 degrees of retard built into the timing set to produce a natural egr effect since some exaust gasses are left in the CC. In reality, though, reusing a crap stock timing set can create cam timing issues but i always thaught it was interesting that GM actually did this.