Torque or power?!

[wopdat]

Hi peeps, I need to know if anybody has tried and tested exhaust systems on a valver.

My valver came with a full janspeed DTM exhaust system when i bought the car a few years back which consisted of 4 boxes including the one on the downpipe. Because i can't stand DTMs i swapped the back box for a small powerflow jobby which had to be modified as it was off scrapped punto. This worked a treat as the pull improved greatly but caused asome bellowing when idling and more so on the motorway.

Next came a miltek 4 in 1 which got rid of the box on the downpipe and increased power. I did notice a slight lack in torque but it was worth it for the power gain at high revs. (system = 3 boxes) 

I then picked up a straight through pipe with a supersprint mid box a sebring rear box... this got rid of the bellowing and sounds lovely when idling (system = 2 boxes)

However, i have lost alot of torque for top end power (revs easily upto 7500 rpm)... but my valver is fookin slow off the line untill it gets goin.

Is this due to a lack of backpressure cos of the lack of boxes? or is it due to the mixin and matchin of the boxes concerned? Or is it somethin completely different?

[danny_p]

the actual boxes themsleves shouldn't have a massive effect really.   the 16v is sensitive to it's exhaust  but the inportant stuff happens in the 1st half of the sytem.  but exhaust theory is a dark art     

[Mew]

I have had a full supersprint system and a full jetex system on the same 8v gti, and to me the supersprint felt like the car pulled harder, especially from lower revs. Don't know if it did actually make a difference or whether it even helps

[6foot6]

Alright fella, with a NA engined car, the exhaust should be matched/tuned to the manafold and engine.

Its all about getting the exhaust pulse flow correct.

On a turbo car smaller pipe run and biggest diameter pipe (up to a point) after the turbo will allow for better turbo response and you dont really have to worry about exhaust pulse flow the same as you do on a NA as the the turbo charger is a big restriction in the exhaust.

Sounds to me like your car is not very nice to drive as your loosing out on Low down torque which is much more usable around town and day to day driving rather than having to ring the cars neck to get it going.

You could try advancing your timing 2 degrees which will help with pickup but will make your car more prone to pinking if you use 95 ron fuel.

[xcore]

anyone suggest a good system to keep or add more torque?

[6foot6]

anyone suggest a good system to keep or add more torque?

stock OEM system

If you really want extra torques only real option is stroker/bore to 1.9liters or fit a SC or Turbo

[Tara]

Torque wins races BHP sells cars 

[6foot6]

Torque wins races BHP sells cars 

Torque gets you off the line, BHP gets you over it

[VeeDubGTI16v]

torques for tractors

[DarnPB]

Power gives you speed. Torque gives you pulling power.