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sports exhuaust how much more bhp

Posted: Sun May 30, 2004 12:13 am
by aparker
Does anyone know how much more bhp a sport exhuaust will give my car. I've got a 1043cc at 45bhp with a twin bore full system and it also had the cat removed.

Posted: Sun May 30, 2004 7:34 am
by Tahrey1043
Dunno...... how much has your top speed increased by on familiar roads? (and from-to) :) I can give you a rough estimate by that...

You might be sitting on a firey 48hp volcano, maybe even 50.

Posted: Sun May 30, 2004 9:37 am
by carmadaaron
full system should gain about 3-6hp.
smaller engines gain less than big turbo'd ones (around 30 for a supra) :lol:

Posted: Sun May 30, 2004 4:22 pm
by aparker
my top speed is about 115mph maybe a bit more but as i brought the car with the exhuaust i don't know what the nornal top speed would be.

Posted: Sun May 30, 2004 4:42 pm
by carmadaaron
normal should b around the 100mph mark! :D

Posted: Sun May 30, 2004 7:36 pm
by Tahrey1043
(i once again stand back in awe at the figures people are posting for their 1-litres)
please sir can i have yours?

I see 90-95 normally, had it up to indicated 107 on a rather substantial downslope. 115.... mm

Posted: Sun May 30, 2004 7:47 pm
by aparker
I know if sound unbeliveable but it is true i got a mate in a 406 (company car not his usual mk2 polo) to drive along side my car at the time to check the speed as i've got larger wheels then what it came with so the speedo is out.

Posted: Sun May 30, 2004 9:43 pm
by robz
115mph in a 1 litre is impressive! ma old polo was a 1litre & i dont fink it even reachd 100mph. The fastest ive had my GT isnt much more than ur speed.

Posted: Sun May 30, 2004 10:13 pm
by hardhitter
You can't really say how much an exhuast will gain you. The only way of finding out is to get it rolling roaded before and after.

Posted: Mon May 31, 2004 1:56 am
by Tahrey1043
Parkie i think you should hold onto that one and get it analysed mate, either it's not actually a 1-litre or something special's going on that we should know about so we can make the neccessary mods to our own!
Back when I was driving my mums Punto I would even have been happy with those speeds, and the thing was almost as rapid as a GT.... (75hp MPi engine in a Golf-size/shape/weight car). Think I got it up to 115 *once* when really, really hammering it and slightly off my box on the craziness of youth.

Posted: Mon May 31, 2004 10:26 am
by carmadaaron
downhill will gain sooo much mph! :wink:

Posted: Mon May 31, 2004 12:24 pm
by optima21
I'd expect very little increase in power as the iinlet side of the engine is very restrictive, and you dont have that much power to begin with.

My 1L mk2 cruises at 80-90 on the motorway in warm weather, but I'm lucky to get a constant 70 in cold weather. I did accidently get upto 95 yesterday, and that was going up a slight gradient, then backed off as I dont like to push the engine too hard, and thats just fitted with standard kwik-fit exhaust system.

in fact I still havent driven my GT as fast as my mk2, but then again the mk2 is more fun to drive

Posted: Mon May 31, 2004 1:40 pm
by Tahrey1043
You lose power in the cold? How wierd :) Mine seems slower now than it did in December!

Posted: Mon May 31, 2004 2:38 pm
by optima21
Tahrey1043 wrote:You lose power in the cold? How wierd :) Mine seems slower now than it did in December!
in a mk2 yes because the fuel has to vapourise to burn propely and the only way it can do that in a carburetted car is by heating the fuel (which is done by the incomming air). Thats why I'm against cold air feeds on carbed cars, they're a waste of time. on a fuel injected car, the fuel pressure causes the fuel to break up into tiny droplets when the injectors are open which leads to more efficient combustion, although the car still needs to run with rich fueling when its started from cold.

Posted: Mon May 31, 2004 7:40 pm
by carmadaaron
you wont be driving fast in winter anyway cus of the road conditions! :wink: