What do you make of these power graphs?

MeEsH BaKkA · 4 Oct 2009 at 10:40

The power comes in nice an early, like a sledgehammer, then drops off fast (overboost valve opening? or maybe some wheelspin on the rollers?) After that, its a steady drop off, almost like the turbo just isnt big enough?

The turbo is pretty tiny, these cars can make 300bhp on the standard turbo but what one person I have spoke to said was that if the boost is set too high you get masive torque gain (300 is about 60lbft up on standard) but the BHP figures fall like a stone. If this turbo is boosting too much then I assume thats why the torque curve is more of a torque arrow?

Matt82 · 4 Oct 2009 at 10:42

that 200sx. thats a proper torque plot. not one of these gay, tiny turbo, diesel esq deliveries

Bear · 4 Oct 2009 at 14:33

Lumeycom said:
^^ My last torque graph before i sold it, top end drop was it wanting a little more lift on the inlet cam

Thats a bit wierd that plot, what turbo did you have on it ?? The turbo looks to be quite big as it takes quite a while to hit maximum torque (4700rpm) but it only makes a tad under 300ft/lbs which makes it a relatively small turbo near standard size. :confused:

Lumeycom · 4 Oct 2009 at 16:07

Dr Who said:
They cross exactly at 5250, try looking at the scales maybe?

Already deal with, try reading the whole post maybe?

Bear said:
Thats a bit wierd that plot, what turbo did you have on it ?? The turbo looks to be quite big as it takes quite a while to hit maximum torque (4700rpm) but it only makes a tad under 300ft/lbs which makes it a relatively small turbo near standard size.

2860 with a .86 exhaust housing. Remember its only a lil 1800cc engine too

I did manage to improve that with a little less timing and more fuel but the EGT's got a little scary so it ended up settled at that

Bear · 4 Oct 2009 at 17:50

Lumeycom said:
2860 with a .86 exhaust housing. Remember its only a lil 1800cc engine too I did manage to improve that with a little less timing and more fuel but the EGT's got a little scary so it ended up settled at that

Ah didnt think about the s13, just thought it was a wierd plot for an s14 which was why I mentioned it.

Lumeycom · 4 Oct 2009 at 17:57

Bear said:
Ah didnt think about the s13, just thought it was a wierd plot for an s14 which was why I mentioned it.

Rocker arms belong on sewing machines and mini's. Fin.

Anyway, enough hijacking - sorry! :E

Clarkey · 4 Oct 2009 at 18:16

Lumeycom said:
Rocker arms belong on sewing machines and mini's. Fin.

Anyway, enough hijacking - sorry! :E

I'm sorry, did you actually just suggest a CA is better than an SR?

Dr Who · 4 Oct 2009 at 18:18

Lumeycom said:
Already deal with, try reading the whole post maybe?

What the part where it said they crossed at 4100 and the RR wasnt set up properly?

Simon · 4 Oct 2009 at 22:44

BigglesPiP said:
Are the dots the samples?

I think the line plotting function is in a bit of a funky mood if this is the case.

Agreed,

If you ignore the stupid 'line of best fit' the actual plot is pretty smooth.

I imagine heatsoak is an issue at higher revs, how long do they hold the car at each sample point?

( |-| |2 ][ $ · 5 Oct 2009 at 13:11

pls delete