c4 performance
Racer
Joined: Jun 2010
Posts: 290
Likes: 5
From: Winona MN
Another great place to buy parts they have great pricing on Magnaflow just follow the directions for an email with your discounted price.
http://www.performancepeddler.com/default.asp
http://www.performancepeddler.com/default.asp
Thread Starter
Intermediate
Joined: Jun 2011
Posts: 46
Likes: 0
From: Eau Claire WI
thanks for the help guys. I am anxious to get the car running and take it to some car shows this summer. as well as drive it (wisconsin has a short summer so i need all the time i can get)
Thread Starter
Intermediate
Joined: Jun 2011
Posts: 46
Likes: 0
From: Eau Claire WI
I'll do the routine tune and see where than gets me. If I need injectors and a y pipe i'll tackle that after i know the basics are good to go. Thanks for the help. Much appreciated.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,062
From: altered state
St. Jude Donor '05
As you said basics are where to start. Timing, check the TPS positioning. things of that nature.
Some seem to run different than others all things being equal for some reason. Friends low mile 88 didnt seem like it had near the responsiveness as an 89 I had but mods were exactly the same, tuneup etc.
Some seem to run different than others all things being equal for some reason. Friends low mile 88 didnt seem like it had near the responsiveness as an 89 I had but mods were exactly the same, tuneup etc.
Racer
Joined: Apr 2011
Posts: 296
Likes: 1
From: Tipp City Ohio
How does one go about "gutting" the cat? Instructions please as I'm installing a cat-back system this week so while I'm down there....
Team Owner
Joined: Sep 2001
Posts: 62,127
Likes: 1,727
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
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Advanced
Joined: May 2011
Posts: 63
Likes: 0
From: Glen Burnie Md
Thats it,I used a long screw driver.Im assuming mine was still the original as it broke apart in less than two minutes.After I put everything back together I did notice at light throttle a whooshing,whistling sound....it was air blowing past the breather tube(which is located in the middle of the gut of the cat,once gutted its free to have lots of air pushed past it...like blowing on the top of a beer bottle).I took a bolt the same size and brazed it in the part of the tube that goes in the cat.May be Im just really picky but it did help.Being a musician maybe my ears are a little more keen to stupid things like this.I did a search and found nothing else on the matter.You might not even notice it.And depending on what mufflers your running the sound may never reach the end off the system,mine are chambered muffler deletes
Racer
Joined: Apr 2011
Posts: 296
Likes: 1
From: Tipp City Ohio
Thats it,I used a long screw driver.Im assuming mine was still the original as it broke apart in less than two minutes.After I put everything back together I did notice at light throttle a whooshing,whistling sound....it was air blowing past the breather tube(which is located in the middle of the gut of the cat,once gutted its free to have lots of air pushed past it...like blowing on the top of a beer bottle).I took a bolt the same size and brazed it in the part of the tube that goes in the cat.May be Im just really picky but it did help.Being a musician maybe my ears are a little more keen to stupid things like this.I did a search and found nothing else on the matter.You might not even notice it.And depending on what mufflers your running the sound may never reach the end off the system,mine are chambered muffler deletes
Do I need to take the cat off to do the gutting or can it be done on the car, connected to the front Y?
Team Owner
Joined: Sep 2001
Posts: 62,127
Likes: 1,727
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
You need to take the cat off to gut it right. It'll be louder when you stand on it, and deeper.
These main cats on L98s cost you about 10hp on a stock car, so it does help the power to gut it.
These main cats on L98s cost you about 10hp on a stock car, so it does help the power to gut it.
Thread Starter
Intermediate
Joined: Jun 2011
Posts: 46
Likes: 0
From: Eau Claire WI
Did the tune up today and it idles much better and pulls hard under full throttle. However from a dead stop when you give it full throttle it won't slip the tires kind of acts like it bogs out then pulls hard. Any ideas guys? The car is an auto not manual if it matters
Max G’s
Joined: Nov 2008
Posts: 2,751
Likes: 78
From: Monroe OH
NCM Sinkhole Donor
Run the car for a while for a week or so and see if it changes. I would run the higher octane. My 91's call for premium only. Not sure about the 87. Regardless, the higher octane will have a more efficient burn and should keep the injectors cleaner. Also, run some fuel injector cleaner or octane booster through a tank once.
Racer
Joined: Apr 2011
Posts: 296
Likes: 1
From: Tipp City Ohio
Run the car for a while for a week or so and see if it changes. I would run the higher octane. My 91's call for premium only. Not sure about the 87. Regardless, the higher octane will have a more efficient burn and should keep the injectors cleaner. Also, run some fuel injector cleaner or octane booster through a tank once.
Thread Starter
Intermediate
Joined: Jun 2011
Posts: 46
Likes: 0
From: Eau Claire WI
I'll give the car two tanks of injector cleaner and higher octane fuel without ethenol and see how it goes. If that doesnt help it sounds like a new cat and new injectors. Unless the auto's are that much different than a stick that was my only other thought where power loss would be impacted vs others. Thanks again
Melting Slicks
Joined: Jun 2002
Posts: 2,705
Likes: 30
From: Chesapeake Beach Maryland
2015 C5 of Year Finalist
Do you know what gears are in the rear? If its highway gears like the later 2.59 A4s, You'll be trying for a while to bust them loose easily from a stand still. Automatic Corvettes with those highway gears just have a hard time doing smokey burnouts with just a pedal dump. My car with stock 2.59 gears and the automatic could hardly break them loose unless there was a little sand or gravel to help out. Seriously, and in stock trim it dynoed at a normal-ish 253 RWHP. Put some crap tires on there and it will spin them easier if that's what your after. But really, traction is the goal.
Thread Starter
Intermediate
Joined: Jun 2011
Posts: 46
Likes: 0
From: Eau Claire WI
the goal isnt to do burn outs i just seem to remember it doing that easier years ago when i was younger. I know it does not have the G92 pkg 3.07:1 Axle ratio so i would assume it has the highway option you mentioned. Perhaps my memory from being younger is off and i know until a few years ago it had the original tires on it and those were im sure not as grippy as the new ones not to mentioned hard and dry so they would slip more easily. Thanks for the help. I just want to make sure nothing is wrong with the car and that it is running correctly. My goal isnt to go tearing around town doing burn outs i dont do that with any of the other cars i have if it can do it its just nice to know and who doesnt like like once in a while just lighting them up
Team Owner
Joined: Sep 2001
Posts: 62,127
Likes: 1,727
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Run the car for a while for a week or so and see if it changes. I would run the higher octane. My 91's call for premium only. Not sure about the 87. Regardless, the higher octane will have a more efficient burn and should keep the injectors cleaner. Also, run some fuel injector cleaner or octane booster through a tank once.
Team Owner
Joined: Sep 2001
Posts: 62,127
Likes: 1,727
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
I'll give the car two tanks of injector cleaner and higher octane fuel without ethenol and see how it goes. If that doesnt help it sounds like a new cat and new injectors. Unless the auto's are that much different than a stick that was my only other thought where power loss would be impacted vs others. Thanks again