checked out a modded thirdgen, I have questions
#1
Senior Member
Thread Starter
Join Date: Dec 2003
Location: Ontario, Canada
Posts: 758
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1988 Pontiac Trans Am
Engine: 5.0L Fuel Injection
Transmission: Automatic 4speed /w OVerdrive
checked out a modded thirdgen, I have questions
Ok. The girlfriend and I went and checked out a TransAm with a 350 and 5 speed. I figured this was a weird combo seeing how the 350 and 5 speed were never options offered together so I had to go see. We get there and I check the VIN and sure enough this thing was an LG4 before. Guy was running it with the stock LG4's carb on this 350 H.O. from GM Performance. Question I have is ... will the stock carb from a 305 LG4 be enough to supply enough fuel and air to this engine, or will the engine lean out.
#2
Member
![](https://www.thirdgen.org/forums/images/ranks/tgo10.gif)
Join Date: Jan 2008
Location: Houston, Texas
Posts: 293
Likes: 0
Received 2 Likes
on
2 Posts
Car: 84' Z28-White/T-Tops
Engine: H code LG4 305
Transmission: TH700R4
Axle/Gears: Stock 3.23
Re: checked out a modded thirdgen, I have questions
It's a perfectly fine carb for the 350 but the secondary's rods may need changed to fine tune it.
#3
Moderator
![](https://www.thirdgen.org/forums/images/ranks/tgo10.gif)
iTrader: (14)
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 43,169
Likes: 0
Received 36 Likes
on
34 Posts
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
The engine won't "lean out", but some stock LG4 q-jets had the secondary air valve travel limited. Check out this tech article linked from the thirdgen.org homepage https://www.thirdgen.org/quadrajet
I know the article says "computer controlled q-jet", but the AV mod applies to either CC or non-CC. since you're in Canada, I'm assuming this is a non-CC q-jet.
I know the article says "computer controlled q-jet", but the AV mod applies to either CC or non-CC. since you're in Canada, I'm assuming this is a non-CC q-jet.
#4
Senior Member
Thread Starter
Join Date: Dec 2003
Location: Ontario, Canada
Posts: 758
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1988 Pontiac Trans Am
Engine: 5.0L Fuel Injection
Transmission: Automatic 4speed /w OVerdrive
Re: checked out a modded thirdgen, I have questions
ok...I was wondering if that carb would lean it out cuz periodically the car will blow a puff of blue smoke...
dude wants 3000 for the car. Body is in ok shape but that 5 speed 350 setup kinda worries me...I offered him a low ball 2000 to see if he would bite...he is pondering it.
dude wants 3000 for the car. Body is in ok shape but that 5 speed 350 setup kinda worries me...I offered him a low ball 2000 to see if he would bite...he is pondering it.
#5
Moderator
![](https://www.thirdgen.org/forums/images/ranks/tgo10.gif)
iTrader: (14)
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 43,169
Likes: 0
Received 36 Likes
on
34 Posts
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Blue smoke is oil. I'm guessing you saw it during/after a shift. You'll probably see it if you restart it 5-30 minutes after turning it off hot.
Valve stem seals. Common SBC problem, relatively simple fix.
Valve stem seals. Common SBC problem, relatively simple fix.
#6
Senior Member
Thread Starter
Join Date: Dec 2003
Location: Ontario, Canada
Posts: 758
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1988 Pontiac Trans Am
Engine: 5.0L Fuel Injection
Transmission: Automatic 4speed /w OVerdrive
Re: checked out a modded thirdgen, I have questions
actually we saw it durring idle
Trending Topics
#8
Supreme Member
Join Date: Oct 2006
Posts: 1,974
Likes: 0
Received 0 Likes
on
0 Posts
Car: 91 RS
Engine: 350 vortec
Transmission: T-5
Axle/Gears: not the best not the worst
Re: checked out a modded thirdgen, I have questions
make sure it actually is a 350... to start then worry if it came from a junkyard
Thread
Thread Starter
Forum
Replies
Last Post