Quick question, I know that most cats are placed close to the engine in order to heat up faster, however does anyone know how detrimental it would be to place it farther back? The context is for another vehicle I'm working on, and i can't seem to find information on it. I just need them on there to pass emissions, as it has no cats right now.
 |
-
-Phil
sigpic
+1982 Ford LTD-S Police Car. Built 351w, Trickflow 11R 190 Heads, Holley Sniper EFI, RPM Intake+ Hyperspark dizzy, WR-AOD, Full exhaust headers to tails. 3.27 Trac-Lok Rear. Aluminum Police Driveshaft. Speedway Springs+Bilstein Shocks, Intermediate Brakes, HPP Steering Box.
+2003 Acura CL Type S 6-speed -
as long as you get it fully up to temperature before running it through, you'll be OK. How far back are we talking though? It needs to be as close to the engine as reasonable, but many applications had a couple feet of pipe between the cat and the engine.86 Lincoln Town Car (Galactica).
5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley
91 Lincoln Mark VII LSC grandpa spec white and cranberry
1984 Lincoln Continental TurboDiesel - rolls coal
Originally posted by phayzer5
I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers
Everything looks like voodoo if you don't understand how it works -
I wouldn't go much past the driver's butt. They gotta heat up to work, and I'd imagine it'd just clog from never self-cleaning or not do any converting if you get it back too far. At that point you might as well just not run one or gut it, as much as I'm not a fan of either of those.
If you wanna get real science-ey, you might get a good answer from Catco or Magnaflow or whoever's tech line. Maybe even find out what the temperature is that they start working reliably, install the cats where you're thinking of, and hit them with an infrared heat gun or whatever to see if they ever get up to temp.
85 4 door 351 Civi Crown Victoria - Summer daily driver, sleeper in the making, and wildly inappropriate autocross machine
160KMs 600cfm holley, shorty headers, 2.5" catted exhaust, 255/295 tires, cop shocks, cop swaybars, underdrive pulley, 2.73L gears.
waiting for install: 3.27's, Poly bushings, boxed rear arms, 2500 stall converter, ported e7's, etc
06 Mazda 3 hatch 2.3L 5AT (winter beater that cost more than my summer car)Comment
-
Would they clog up faster if positioned further away from the motor ?
Comment
-
mine are just south of the down pipe bend on the level end. No issues passing smog and the place is only a 5 minute drive from me.
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
Originally posted by gadget73
... and it should all work like magic and unicorns and stuff.
Originally posted by dmccaig
Overhead, some poor bastards are flying in airplanes.Comment
-
can you get historic plates on the car and be exempt?
1986 lincoln towncar signature series. 5.0 HO with thumper performance ported e7 heads, 1.7 roller rockers, warm air intake, 65mm throttle body, 1/2" intake spacer, ported intakes, 3.73 rear with trac lock, 98-02 front brake conversion, 92-97 rear disc conversion, 1" rear swaybar, 1 3/16" front swaybar, 16" wheels and tires, loud ass stereo system, badass cb, best time to date 15.94 at 87 mph. lots of mods in the works 221.8 rwhp 278 rwt
2006 Lincoln Town Car Signature. Stock for now
1989 Ford F-250 4x4 much much more to come, sefi converted so far.
1986 Toyota pickup with LSC wheels and 225/60/16 tires.
2008 Hyundai Elantra future Revcon toad
1987 TriBurner and 1986 Alaska stokers keeping me warm. (and some pesky oil heat)
please be patient, rebuilding an empire!
Comment
-
I had a station try to hold Putter Project up because of the lack of a cat. I told him that it says emissions delete on the rad core badge. He still wouldn't test it. Then he tried to convince me that I couldn't bring it to any oter place; which I did. And Putter Project passed. If I get a big block in there, I will probably have to get cats for it; though I may try to get QQ plates since I don't drive the truck that much.
PackmanComment
-
hold ze phone, 74 fords and some 75 fords did not come with cats
1986 lincoln towncar signature series. 5.0 HO with thumper performance ported e7 heads, 1.7 roller rockers, warm air intake, 65mm throttle body, 1/2" intake spacer, ported intakes, 3.73 rear with trac lock, 98-02 front brake conversion, 92-97 rear disc conversion, 1" rear swaybar, 1 3/16" front swaybar, 16" wheels and tires, loud ass stereo system, badass cb, best time to date 15.94 at 87 mph. lots of mods in the works 221.8 rwhp 278 rwt
2006 Lincoln Town Car Signature. Stock for now
1989 Ford F-250 4x4 much much more to come, sefi converted so far.
1986 Toyota pickup with LSC wheels and 225/60/16 tires.
2008 Hyundai Elantra future Revcon toad
1987 TriBurner and 1986 Alaska stokers keeping me warm. (and some pesky oil heat)
please be patient, rebuilding an empire!
Comment
-
Some didn't but this one was a 6 cylinder and it did come with cats...if it originally had the 302 it may not have though. I have to go measure but i'd say at least a good 4 feet away from the engine.
Historic plates down here suck, you basically can't drive the car, and this is going to be a driver so that's no bueno.-Phil
sigpic
+1982 Ford LTD-S Police Car. Built 351w, Trickflow 11R 190 Heads, Holley Sniper EFI, RPM Intake+ Hyperspark dizzy, WR-AOD, Full exhaust headers to tails. 3.27 Trac-Lok Rear. Aluminum Police Driveshaft. Speedway Springs+Bilstein Shocks, Intermediate Brakes, HPP Steering Box.
+2003 Acura CL Type S 6-speedComment
-
What's stopping you from placing it close to the engine? On Chevy trucks there's the downpipes then the cats are placed about 6-9 inches down from where it first levels out, no problems like that. My Sierra is like that, cheap highflow cat but we have no testing, I could get rid of it and have no issue.
Put it as close to the engine as possible, right off the manifolds is ideal but that's a huge pain. I'd say weld flanges to the cat on each side, then flanges on the exhaust pipe. You can have a flanged pipe the same length, then you can bolt up the cat only when needed for testing, the rest of the time no cat.88 Town Car (wrecked, for sale)
Walker OEM duals with muffler deletesComment
-
the "Custom" nature of the exhaust. I went out and measured, it's really only about 3 feet of pipe away from the heads, so it should be fine...
my other concern is that it is a V8 engine swap in a 6 cylinder car. Although the engine is newer, one that could have come in the car. Also i have no idea if DMV can even decode a 75 vin to be able to tell what engine it used to have.
If I'm putting cats in, they are going to stay in there, I like cats.-Phil
sigpic
+1982 Ford LTD-S Police Car. Built 351w, Trickflow 11R 190 Heads, Holley Sniper EFI, RPM Intake+ Hyperspark dizzy, WR-AOD, Full exhaust headers to tails. 3.27 Trac-Lok Rear. Aluminum Police Driveshaft. Speedway Springs+Bilstein Shocks, Intermediate Brakes, HPP Steering Box.
+2003 Acura CL Type S 6-speedComment
-
This is for the Maverick right? I like no cats on old cars, but it's your choice. Thunderbolt cats are decent, I have one on my Sierra, good for the price, got mine for $40 on performance-curve.com, price gas gone up a bit but not too much. I think Ebay has them too.88 Town Car (wrecked, for sale)
Walker OEM duals with muffler deletesComment
-
On my pickup the cats where a good 4-6 feet from the manifolds. Basically under the bed just ahead of the mufflers. Put them there so they would be out of the way when it came time to work on the gas tank, or fuel lines. For as much space as there is under the truck, trying to reach some of the fuel line clamps was a real chore with the cat taking up space my arm could have used, then I decided they where getting moved. =-)
No ill effects from having them there. Pretty certain I already had them that far back when the truck still needed e-testing.
Alex.Comment
-
there are super compact cats out there that can weld in easilly, they run about 50 each............i would try to keep them close to the engine.
1986 lincoln towncar signature series. 5.0 HO with thumper performance ported e7 heads, 1.7 roller rockers, warm air intake, 65mm throttle body, 1/2" intake spacer, ported intakes, 3.73 rear with trac lock, 98-02 front brake conversion, 92-97 rear disc conversion, 1" rear swaybar, 1 3/16" front swaybar, 16" wheels and tires, loud ass stereo system, badass cb, best time to date 15.94 at 87 mph. lots of mods in the works 221.8 rwhp 278 rwt
2006 Lincoln Town Car Signature. Stock for now
1989 Ford F-250 4x4 much much more to come, sefi converted so far.
1986 Toyota pickup with LSC wheels and 225/60/16 tires.
2008 Hyundai Elantra future Revcon toad
1987 TriBurner and 1986 Alaska stokers keeping me warm. (and some pesky oil heat)
please be patient, rebuilding an empire!
Comment
-
Those Thunderbolts come in standard style, and the compact spun cat style. I have the spun on my truck, since I wanted highflow.88 Town Car (wrecked, for sale)
Walker OEM duals with muffler deletesComment
Comment