4.2 rolling roaded

4.2 rolling roaded

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Tam Lin

Original Poster:

694 posts

260 months

Thursday 24th April 2003
quotequote all
As mentioned by SGirl on the kiddy-seat thread, we chucked the Cerb (pics coming when it stops peeing down) on the Rolling Road at Power Engineering, and we got what I assume are reasonable out of the box figures: 254 bhp at the wheel(s), 336 flywheel at 6066 rpm, but "only" 298 Lbs/ft torque.

A set of Nitron dampers/stiffer strings are clearly on the shopping list, but engine-side, I seem to remember reading a while ago a point by DannyLT that Joolz has an induction side fix that gives a wee bit more torque. Anyone had this done/any thoughts on the matter?

olly

2,174 posts

291 months

Thursday 24th April 2003
quotequote all
That power figure is about normal for a 4.2, but the revs are reasonably low (relativly speaking), so at least you don't have to drive it REALLY hard to get to all the power...

Joolz does do several mods, the most simple probably being a pair of cone air filters. Those alone will make virtually no difference to power, althoguh they will always perform the same way (i.e. the same as a brand new standard filter), but they will never needs replacing again. When was the car last serviced ?

joospeed

4,473 posts

285 months

Thursday 24th April 2003
quotequote all
all very true Olly.
that torque is quite low .. typically the figure I see for 4.2 cars that make good power - ie those cars that make low peak torque but hold that figure high up the rev range to make good power figures.
More important than peak torque is the spread though .. if you've got 298 all the way from 2k revs upwards then don't worry too much .. if it's low all over though there's a million and one reasons why that could be.

markoso

52 posts

287 months

Friday 25th April 2003
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Excuse my ignorance but from what i've read on PH there seems to be generally little difference in BHP 'tween the standard 4.2 & 4.5 (please tell me if i am talking out of my a...)is there any more torque usually with the 4.5?

dannylt

1,906 posts

291 months

Friday 25th April 2003
quotequote all
Search back through previous thread I guess, but yes, little difference in overall power, though 4.5 generally have more low down torque.

Tam Lin, as for increasing the power of your 4.2, Joolz can port the 4.2 inlets which I seem to remember can gain you another 15 or so?

danny

Tam Lin

Original Poster:

694 posts

260 months

Friday 25th April 2003
quotequote all

joospeed said: that torque is quite low .. More important than peak torque is the spread though .. if you've got 298 all the way from 2k revs upwards then don't worry too much ...


Thanks to all for input.

Joolz, no doubt you will see the Cerb sooner rather than later (ever thought of moving down south? Much higher house prices, crowded roads, superb trafic calming schemes..you know it makes sense), so we can discuss the 1000 & 1 reasons. Torque at 2750 is 270, and "peaks" at what looks like 5500, then goes south at about 6100. (Not in work. Can't scan)

As far as preliminary investigations reveal, the thing's got a 4.5 back box (baffles periodically patched up by just about every independent in the car's history, judging by the receipts), and the fact that the Lambda sensors seem not to be wired up to anything leads me to suspect I need to check whether the cats are present & accounted for still, it's got a fresh MOT from the dealer..so it MUST be ok

gazzab

21,232 posts

289 months

Friday 25th April 2003
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Dont think that MOT always equals CATS even if a dealer has sorted the MOT.