Emmisions question
Thread Starter
5th Gear
Joined: Jul 2002
Posts: 5
Likes: 0
From: Rose Hill KS
Emmisions question
I was thinking of replacing the egr manifold with a performer and removing the other emission control. What kind of performance change have you gotten from removing your guys emissions. :confused:
Melting Slicks
Joined: Apr 2001
Posts: 2,280
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From: colorado springs CO
Re: Emmisions question (1975vette)
you will notice a little bit of a difference with the 2101 manifold.... also plugging the heat crossover is supposed to give you a bit more HP although i imagine itll take a bit longer to warm up...
but after putting on the 2101 i noticed a difference...
however id do the whole package instead of working twice.... swap out the heads and cam and lifters etc while you have the other stuff off..
also recurve your distributor.....
but after putting on the 2101 i noticed a difference...
however id do the whole package instead of working twice.... swap out the heads and cam and lifters etc while you have the other stuff off..
also recurve your distributor.....
Drifting
Joined: Jun 2000
Posts: 1,752
Likes: 1
Re: Emmisions question (1975vette)
welcome to the forum!
I swapped in the Performer EGR manifold and removed some emissions (temporarily) :blueangel:
I didn't notice any changes removing the emissions stuff (unfortunately - I really I WANTED to) :)
Biggest change came in with true dual exhaust with no cats (yet :blueangel: ) and aluminum heads. I had intake/comp cams 268h and they didn't provide much boost until I did the exhaust/headers. The aluminum heads were icing on the cake.
So, I wouldn't do intake without doing exhaust work FWIW.
-terry
I swapped in the Performer EGR manifold and removed some emissions (temporarily) :blueangel:
I didn't notice any changes removing the emissions stuff (unfortunately - I really I WANTED to) :)
Biggest change came in with true dual exhaust with no cats (yet :blueangel: ) and aluminum heads. I had intake/comp cams 268h and they didn't provide much boost until I did the exhaust/headers. The aluminum heads were icing on the cake.
So, I wouldn't do intake without doing exhaust work FWIW.
-terry
Thread Starter
5th Gear
Joined: Jul 2002
Posts: 5
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From: Rose Hill KS
Re: Emmisions question (daily_driver)
Do you also recommend changing the carbureator. A 750q-jet sounds like to much for a 165hp 350 but then again I'm still young and don't know anything.
It has the dual exhaust without a cat but I was going to change the mufflers to 40 series flowmasters
[Modified by 1975vette, 7:31 PM 7/25/2002]
It has the dual exhaust without a cat but I was going to change the mufflers to 40 series flowmasters
[Modified by 1975vette, 7:31 PM 7/25/2002]
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Re: Emmisions question (1975vette)
Removing the EGR valve etc is not much of a gain. Check out the smog police first to make sure you are not getting upside a problem with inspections. A better flowing intake will only show margional gains until you change the cam to breathe better and get a freeer flowing exhaust.
As far as the Q-Jet goes, 750cfm only happens with WOT. Your carb is jetted for fuel flow for your engine so it is not too big.
As far as the Q-Jet goes, 750cfm only happens with WOT. Your carb is jetted for fuel flow for your engine so it is not too big.
Thread Starter
5th Gear
Joined: Jul 2002
Posts: 5
Likes: 0
From: Rose Hill KS
Re: Emmisions question (bigvette1)
How hard of a job is it to change out cam and heads, or how much does it cost to get something like that done. I have the time to learn.
[Modified by 1975vette, 9:04 PM 7/25/2002]
[Modified by 1975vette, 9:04 PM 7/25/2002]
Melting Slicks
Joined: Apr 2001
Posts: 2,280
Likes: 0
From: colorado springs CO
Re: Emmisions question (bigvette1)
the qjet has vacc secondaries.....
its a keeper!!!
if you need to rebuild it and dont wanna do it yourself.... then consider LARS hes a qjet god.... or you can order one of the edelbrock qjet replacements from summit racing... i got one of those and it works great...
its a keeper!!!
if you need to rebuild it and dont wanna do it yourself.... then consider LARS hes a qjet god.... or you can order one of the edelbrock qjet replacements from summit racing... i got one of those and it works great...
Melting Slicks
Joined: Apr 2001
Posts: 2,280
Likes: 0
From: colorado springs CO
Re: Emmisions question (daily_driver)
its not hard at all./.. you just have to take your time and do it right the 1st time (like coating bolt threads with RTV and torquing everything down right (especially aluminum intake!!!)
if you rush it, then youll have leaks....
the other problem is doing the "while your at its"...
:lol: :lol:
"well im gonna have the timing gear/chain offf might as well install a new one....."
"well might as well go roller rockers..."
"well might as well go with more $$$ heads....."
"well might as well go full roller"
"well...welll..wellll.."
ROTFL
by the time your done youll have a blower sticking outta your hood
:cheers:
if you rush it, then youll have leaks....
the other problem is doing the "while your at its"...
:lol: :lol:
"well im gonna have the timing gear/chain offf might as well install a new one....."
"well might as well go roller rockers..."
"well might as well go with more $$$ heads....."
"well might as well go full roller"
"well...welll..wellll.."
ROTFL
by the time your done youll have a blower sticking outta your hood
:cheers:
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Melting Slicks
Joined: Apr 2001
Posts: 2,280
Likes: 0
From: colorado springs CO
Re: Emmisions question (daily_driver)
ive got the 2 chamber flowmasters (is that the 40's??? i forget) and i love em!!
very loud!!
everyone notices a resonance with them around ~1500-1800 though....
very loud!!
everyone notices a resonance with them around ~1500-1800 though....
Thread Starter
5th Gear
Joined: Jul 2002
Posts: 5
Likes: 0
From: Rose Hill KS
Re: Emmisions question (daily_driver)
If the emmisions isn't what is holding the engine down so much what made them only produce 165hp. Again I don't know that much of anything about this.
Drifting
Joined: Jun 2000
Posts: 1,752
Likes: 1
Re: Emmisions question (1975vette)
The exhaust is hurting you. See corvettefaq.com for "Ganey's Exhaust topic". He talks about it. Exahust alone gets you over 200hp. Then do heads/cam/intake and you'll be roundabouts 300hp.
good luck!
-terry
good luck!
-terry
Racer
Joined: Mar 2001
Posts: 326
Likes: 44
From: Newberg,Oregon,U.S.A.
Re: Emmisions question (1975vette)
The stock cam is the biggest culprit along with 8.5-1 cr, I to have the same engine but I just rebuilt it with 9.0-1cr and a comp cam XE256 cam, I also gasket port matched the int & exh and ballanced the crank assembly. Next will be dual exhaust but I need to leave the cats on because of the emission law here :mad I also put on a performer int w/egr and the stock Q-jet works great thanx to Lars and the "parts loaner program"
[Modified by stingraynick75, 12:31 PM 7/25/2002]
[Modified by stingraynick75, 12:31 PM 7/25/2002]
Drifting
Joined: Jul 1999
Posts: 1,542
Likes: 43
From: Plano TX
Re: Emmisions question (daily_driver)
I removed the EGR on my L82 and then had ping problems. Put it back on instead of retrding the timing.
I now have the ZZ4 motor in my car with all stock emissions and this thing really makes great power. As mentioned above, it's not the emissions equipment.
FYI the ZZ4 does not have EGR passages in the head, even though the intake has a place for it. I have to get a vacuum advance with less advance to stop pinging under light load. I plan on going to EGR aluminum heads (exhaust cross over) in the near future, so I can move the timing up. Since the EGR is only used at part throttle it has no impact on performance, except that it will let you run more timing, actually increasing power.
Removing emissions equipment is an old myth, plus I like trying to keep the air I breath as clean as possible.
I now have the ZZ4 motor in my car with all stock emissions and this thing really makes great power. As mentioned above, it's not the emissions equipment.
FYI the ZZ4 does not have EGR passages in the head, even though the intake has a place for it. I have to get a vacuum advance with less advance to stop pinging under light load. I plan on going to EGR aluminum heads (exhaust cross over) in the near future, so I can move the timing up. Since the EGR is only used at part throttle it has no impact on performance, except that it will let you run more timing, actually increasing power.
Removing emissions equipment is an old myth, plus I like trying to keep the air I breath as clean as possible.
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Re: Emmisions question (DaveL82)
What Davel82 says is very true. The stock engines and carbs were jetted with the EGR putting exhaust gas +unburnt fuel back in the flow. Take off the EGR and you get a lean condition. Pings and runs hotter (god knows vettes don't need an excuse to run hotter).
DAVEL82 stated.......
"Removing emissions equipment is an old myth, plus I like trying to keep the air I breath as clean as possible" There is lot we can do to increase performance and still be responsible.
DAVEL82 stated.......
"Removing emissions equipment is an old myth, plus I like trying to keep the air I breath as clean as possible" There is lot we can do to increase performance and still be responsible.
