2004 Chevy Monte Carlo SS

L67 Throttle Body
Prepped Fall of 2010 - Planned install Spring 2011
*** Retired 2014 due to L26 Aluminum UIM Swap and an updated Throttle Body! ***

Project Background/Research - After doing some research into mods I wanted to perform, I saw that it was pretty common for people to buy a Stage 1 ZZP High Velocity Throttle Body.   The difference is the factory throttle body has a 65mm throat and the ZZP model has a 68mm throat.   On the Stage 2, they also remove the MAF "hump" (this requires some re-tuning to the PCM as it changes the MAF tables).

I found that the L67 (3800 SuperCharged) uses a very similiar throttle body as the stock L36.   The main differences are that the L67 has a 69mm throat and the exit port is circular (the L36 has 65mm throat and a more oval shape).   Otherwise, it should bolt right up with no problem.    The pic below on the left is an L67 and on the right is an L36.


Project Goal - My goal now was to attempt to modify a L67 throttle body to be similiar to the Stage 2 ZZP Thottle Body, by sacrificing some of my time to do it for less then it cost to buy.   I opted to look for a unit from a '97-'99 L67, as I understand those models have a MAF "bridge" (vertical metal piece infront of the MAF) and the later models have the MAF "hump" (it's easy to remove the MAF bridge, but others found that when trying to remove the "hump", you will grind a hole through the throttle body).   Pics below show one with the "hump" and the other with the "bridge".

My donor came from a 1997 L67 in a Buick Park Avenue Ultra sitting in a Pull-A-Part.    Please take note, I will discuss later on that since I have a '00 and up model MAF sensor and my donor throttle body is a '97-'99 generaction, the MAF opening on the top will need ported to accomodate my stock MAF sensor.

WARNING!!   Please Read - If you decide to do what I have done here, wear safety glasses/goggles!   I admit, I typically engage in tasks like this without them (typically my prescription glasses protect my eyes).   One night, I did get very tiny shard of aluminum under my eye lid.   Luckily, in the emergency room, the doc saw the shard and successfully removed it without a problem and luckily my stupidity did not cause any long standing problems.   I learned my lesson.   So please, learn from my mistake and wear proper safety gear.   I will not be held responsible for mis-haps by attempts to perform these tasks.

Before I continue, I want to give a special thanks to 95NASTA (I found him on http://www.pontiacbonnevilleclub.com).    I found one of his write-ups about this very idea I had and during the course of my project, I hit him up with some questions.   He was very helpful and it gave me the confidence to know I was going in the right direction, seeing how someone else did the same thing.

The proceeding links document my process of using a '97 L67 Throttle Body, porting the front MAF bridge and correcting the rear outlet mating surface for use this spring with my '04 L36.

-->L67 Throttle Body Project Description
Donor Throttle Body
MAF Bridge
JB Welding
Exit Flare
Polished Inside
Final Product

2004 Monte Carlo SS Page

fb-cam2.jpg (5620 bytes)