Old car + Catalytic converter = hp?

[jet1991]

Why does adding a catalytic converter to a car that doesn`t have one increase it`s power? Catalytic converters steal a certain percent of your engines power, even if it`s a racing cat But maybe I shouldn`t complain, it does give me a cheap power increase.

 

[shirakawaa]

There also are many cars that shouldn't be able to get an ECU upgrade (although one could object that it might be a fuel injection conversion). Carburated cars also aren't supposed to have a rev-limiter.

 

[jet1991]

There also are many cars that shouldn't be able to get an ECU upgrade (although one could object that it might be a fuel injection conversion). Carburated cars also aren't supposed to have a rev-limiter.

Yes you`re right. Most of the old muscle cars stop accelerating at somewhere around 120 MPH, but without the rev limiter the same cars would have reached higher speeds (and then thrown con rods at you) as in real life. The real top speed on these cars depends on how much you dare to push your car.

It would have been cool to have this implemented with a small warning on the screen each time you pushed the car too much.

Edit: you can add rev limiters to carburetted cars (at least 1. gen chevy small blocks) with an electronic ignition or a older engine converted to electronic ignition.

 

[crunchMONKY78]

Nevermind.

 

[shirakawaa]

I've just recalled that some carburated cars did have some sort of rudimental rev-limiter, by the way (usually operating on the spark ignition advance or cutting off ignition spark completely)! Most didn't however.

 

[RC45]

There also are many cars that shouldn't be able to get an ECU upgrade (although one could object that it might be a fuel injection conversion). Carburated cars also aren't supposed to have a rev-limiter.

LOL - they used the old "mechanical' rev limiter. The rod punching through the block pretty much limits your revs to 1rpm less than you pushed the car to hehehe

 

[JackC8]

I also don't understand why you can use a better catalytic converter to increase horsepower even after you've installed the racing exhaust - I'm pretty sure that would eliminate the catalytic converter altogether

 

[fitftw]

adding a cat to a car that doesn't have one should result in a loss of 1 or 2hp in real life...I have a test pipe on my car and it adds some pep.

 

[shirakawaa]

I also don't understand why you can use a better catalytic converter to increase horsepower even after you've installed the racing exhaust - I'm pretty sure that would eliminate the catalytic converter altogether

I think that exhausts upgrades in GT5 are cat-back systems.

 

[articzap]

There also are many cars that shouldn't be able to get an ECU upgrade (although one could object that it might be a fuel injection conversion). Carburated cars also aren't supposed to have a rev-limiter.

Instead of ECU it should be called tuning. All cars can benefit from a tune, be it by a computer or a screwdriver.

 

[SuperCobraJet]

Carburated cars also aren't supposed to have a rev-limiter.

I beg your pardon, I had a 1972 Mustang with a factory rev-limiter.

 

[shirakawaa]

I added that some carburated cars had a rev limiter in post #5.

 

[Troux]

For years it's been weird like this. Remember when you could up the displacement on a handful of Honda motors (maybe a couple other Japanese ones), but not to any American motors? We also still can't turbocharge a lot of cars.

It would be a lot more interesting if you had the same compromises as in real life, i.e. a turbo costs more for a Supra than for a Civic, but the Supra gains a lot more for it, or an NA car costs the same to get a Stage 1 turbo as a stock turbo car, but an NA requires an engine build to get the larger turbos/higher boost.

 

[supersub7]

I've just recalled that some carburated cars did have some sort of rudimental rev-limiter, by the way (usually operating on the spark ignition advance or cutting off ignition spark completely)! Most didn't however.

Yes the limiter was in the distributer cap of some cars. The Ford RS1600 had one, If you took it out the engine would rev for what seemed like ever.

 

[ZBlacktt]

My MKIV Supra's 4" system

My Z32's 3" system

 

[rileyra]

My MKIV Supra's 4" system


My Z32's 3" system

what does your different model turbo and exhaust setup have to do with the subject?


and I'll have to check when bob is done but I coulda swore that it installs a straight pipe instead of a cat... Edit: was wrong it does say cat, shoulda just went straight cutout

 

[ZBlacktt]

what does your different model turbo and exhaust setup have to do with the subject?


and I'll have to check when bob is done but I coulda swore that it installs a straight pipe instead of a cat...not 100% on that though

Cats, no cats, more Hp... if it's over your head. Then just response to the OP. You should also try and refrain from quoting all picture's. No need to see it all posted again and again again if everyone else did it too. Keeps the thread cleaner looking.

 

[rileyra]

Cats, no cats, more Hp... if it's over your head. Then just reponse to the OP.

Oh ok, I was simply asking for your logic behind the pics but instead you choose to go the douche route?

How is it over my head? yer telling me a boosted supra running an open downpipe is the same as changing the cat on an old carburated car? Unless i misread everything in this thread I believe they have been talking mostly about ecu/fuel management for older cars... But now I see why you posted, because someone mentioned a turbo supra setup and you just wanted to show off, well in that case gratz ricer


Edit: Happy? I took the IMG tags out for you so you don't have to scroll another 12 inches down the page.

 

[BrutherSuperior]

I think these types of upgrades on questionable cars really comes down to the fact that you can buy said upgrade and gift it to someone. In essence, it's a modular upgrade system with a few exceptions (BMW & turbos comes to mind).

But if adding a racing cat to a pre-smog car is keeping you up at night, think of it as adding an H-pipe to an otherwise true dual exhaust.