C4 Max Flow Catalytic converter
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Joined: Sep 2011
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From: Woodbury MN
C4 Max Flow Catalytic converter
Hi, I understand the factory exhaust system on my '85 is very restrictive. I'm considering installing a Max Flo converter and am wondering a few things. Has anyone had experience with Mid America Motorworks products? Has anyone installed this catalytic converter? Is it going to be a lot louder then my stock system? Can I expect an increase in MPG? Any comments would be great. Thanks, JFC
Burning Brakes
Joined: Jun 2003
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From: Niagara Falls ON
Mid America is a retailer. They offer products and services that others offer. They are a good company for supporting the Corvette hobby. You can choose to purchase through them or any other retailer.
I don't think that the catalytic converter will affect the sound...but I could be wrong.
If your current catalytic converter is a problem then you can expect that your mpg's will improve. If not then you may not notice a difference.
Are you trying to get better performance or fix a problem?
I don't think that the catalytic converter will affect the sound...but I could be wrong.
If your current catalytic converter is a problem then you can expect that your mpg's will improve. If not then you may not notice a difference.
Are you trying to get better performance or fix a problem?
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From: Woodbury MN
I'm trying to improve gas mileage and performance. There is no problem other than it can get warm in the interior. They claim the car will run cooler and have less restricted exhaust thus improving mpg and performance. Down side is its $218 shipped to my place.
Burning Brakes
Joined: Jun 2003
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From: Niagara Falls ON
The interior of all Corvettes get warm
The car will run cooler IF the old cat is plugged. If it isn't then it will still be warm because Corvettes run warm.
Be careful spending money on performance for a C4...some kid in a Honda will pull up beside you and blow your doors off. Spending money on performance can get expensive fast and you may not get the result that the ads claim.
Also, it is an early C4...don't compare the gas milage that it gets to todays vehicles. It was amazing gas milage in its day, and it still performs well that way, but 30 years of development time has passed.
If you truly need a new cat a magnaflow will do the job...not sure if it is much cheaper though.
The car will run cooler IF the old cat is plugged. If it isn't then it will still be warm because Corvettes run warm.
Be careful spending money on performance for a C4...some kid in a Honda will pull up beside you and blow your doors off. Spending money on performance can get expensive fast and you may not get the result that the ads claim.
Also, it is an early C4...don't compare the gas milage that it gets to todays vehicles. It was amazing gas milage in its day, and it still performs well that way, but 30 years of development time has passed.
If you truly need a new cat a magnaflow will do the job...not sure if it is much cheaper though.
Intermediate
Joined: Apr 2011
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Just a thought on the Magnaflow converters... I was installing new mufflers on my 85 and thought it would be a good idea to replace the converter as well. I tried two different Magnaflow direct fit units before I gave up and put the old converter back on. Both new units had significant front/rear flange bolt hole and air tube alignment issues.
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Mid America is a retailer. They offer products and services that others offer. They are a good company for supporting the Corvette hobby. You can choose to purchase through them or any other retailer.
I don't think that the catalytic converter will affect the sound...but I could be wrong.
I don't think that the catalytic converter will affect the sound...but I could be wrong.
You can also choose to buy a universal from your local muffler shop. Might cost you less.
Muffler shops can tell if your cat is clogged just by looking at it. They discolor due to the build-up in heat. Often, the brick breaks loose and rattles too. Simple tap of the pipe and inspection to see if you "need" one.
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Joined: Sep 2011
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From: Woodbury MN
a few thoughts. It seems like there are varying opinions about the affects of 160 thermostats. Back in the day (late 60s/early 70s) we used to run 160 in the summer and 192 in the winter (here in Minnesota). I never can remember any engine damage from doing this. The motors I'm referring to were small block Chevys. Anyhow, I think I might try this for several reasons; one is that I don't push my '85 at all partly because of gas prices and partly because I don't know the reliability of the components. The cars I used to drag race could hold up to lots of burn outs and banging gears. I'm not sure my '85 would hold up to that stuff. The other reason is that a thermostat is a pretty cheap way to see if I can get the car to run cooler. Yesterday in rush hour with the air on it was up to 230 degrees. Seems a bit high to me. Any additional thoughts would be appreciated. Jay
Le Mans Master
Joined: May 2004
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From: Hellinois
Finalist 2020 C4 of the Year - Modified
Just what is your mileage? My '85 got 29 mpg when it was stock. (On the highway, 70 mph with the air on) It is now a modded 383 and still gets 26. If your figures match this then you aren't going to gain a thing except possibly a louder exhaust like greggpenn said. If they are considerably less then you need more than a cat.
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From: San Diego, Ca
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From: Woodbury MN
Mileage reply
Just what is your mileage? My '85 got 29 mpg when it was stock. (On the highway, 70 mph with the air on) It is now a modded 383 and still gets 26. If your figures match this then you aren't going to gain a thing except possibly a louder exhaust like greggpenn said. If they are considerably less then you need more than a cat.
Burning Brakes
Joined: Jun 2003
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From: Niagara Falls ON
If you put a 160 stat in it will simply open at 160. If the rad can't cool the coolant then the car can still run warm.
The temps that you describe are normal for that car.
Also, in old school cars there wasn't a computer looking for specific temps. If you put a 160 in an 85 then the computer will still try to turn the fans on at a much higher temp. Also, the system will still be looking for that higher temp for other functions...unless you change the chip.
Like I said earlier, if the temp isn't dropping then it is the inefficiency of the rad. Have you cleaned the rad properly? That is the cheapest solution.
The temps that you describe are normal for that car.
Also, in old school cars there wasn't a computer looking for specific temps. If you put a 160 in an 85 then the computer will still try to turn the fans on at a much higher temp. Also, the system will still be looking for that higher temp for other functions...unless you change the chip.
Like I said earlier, if the temp isn't dropping then it is the inefficiency of the rad. Have you cleaned the rad properly? That is the cheapest solution.
Pro
Joined: Nov 2004
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From: Frisco TX
My 89 runs at the same temperatures as your 85. I have a stock stat in it and the main fan is not expected to turn on until the coolant hits 228 to 230 degrees. Pop your hood and watch the fan to make sure it's coming on. But seeing 230 while setting in traffic is to be expected.
As someone else mentioned, if you go to a 165 or 170 degree stat it will not really make a difference unless you are moving. If you are sitting in traffic it will still get up to 228 before the fans come on. If you want the fans to come on earlier you will have to replace the fan temperature switch as well.
Tim
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From: Woodbury MN
I haven't cleaned the radiator but I just got the car last September. It has 95,000 on it and I don't know that it's ever been cleaned. Are you referring to flushing it out as a good cleaning?
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From: Woodbury MN
Thanks, Tim. The more i read the more accepting I am becoming of the 200+ temps. My other vehicle (2003 F-150) doesn't tell the degrees on the temp gauge so when I see the temps in my vette they just seem high. I would appreciate any other comments you might have. This is my first Corvette and I'm loving it. I would like to take it to Colorado Springs this Summer but my wife doesn't quite enjoy the car like I do. Have a good day. Jay
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From: Hellinois
Finalist 2020 C4 of the Year - Modified
I have a custom chip that requires a 160 stat and the fan comes on at 180. Notice I said fan, my outer fan almost never runs unless a/c is on. My car runs around 168 on an 80 degree day and rarely sees 200 in traffic. Now before the naysayers chime in about that being too cool, just keep it, my engine has ran like that now for at least 8 years. I just had it down for a cam change and I dropped the pan and one head and there is no sign of anything out of the norm.