got a boost gauge fitted? (real one not liqui)
boost will be pretty high to get a flutter..
check DV is staying shut also.. if yellow spring already consider some shims to see if this changes it
-
Hey Guest👍👎 We're looking for reviews of your local CUPRA or SEAT Dealership - it's quick and easy to do: Leave a review now
80mm tips are now a must for LCR's
- Thread starter seatcupramad23
- Start date
got a boost gauge fitted? (real one not liqui)
boost will be pretty high to get a flutter..
check DV is staying shut also.. if yellow spring already consider some shims to see if this changes it
Thanks Bill. No boost gauge, not yet anyway, guess I should get one soon. On the rollers recently the boost spiked at about 23.5psi = 1.6 bar, see below. DV is already on a fresh yellow spring, I've got a couple of shims so I'll stick one in and see if that helps at all.
Should I be thinking about cutting the boost back at all? Can change with the SPS.
see thats odd i don't understand how dyno's work , i made 270bhp @ flywheel and 245bhp @ the wheels , but how can i make same hp at the wheels as sam bryant but he runs more power from the engine can someone explain please very curious ?
Can be anything from happy rollers, higher rolling losses, worn diff bearings, stickier tyres, what gear its run in etc etc. so many variables. mine was run by tufty at one point, and he just deasccelerated marginly without dipping the clutch and my 285 went up to 327!
wheels/tyres/pressures, gear tested in......... all will have an effect on coastdowns... so just using atw figures is subject to all of these unknowns. add to that good ole lottery, it further shows why comparisons rarely equate
thanks for that insight bill helpful as always , would say my bhp figures seem pretty accurate , on rollers maf maxed figure was 220 g/s on the rollers quick logged showed 224 g/s on the road boost peaks at 1.5bar and steadily drops 1.2.
270bhp and 306ft/lbs @engine , niki told me car had more power but on stock side mounts not gonna push was happy with result the torque figure did concern me at first but assure he gave it a linear map to keep rods in check . dyno was friendly guy in hinkley
Last edited:
Torque figures vary so much. mine was given a graph of 304lb-ft from a tuner in wolverhampton. bills rollers showed 60lb-ft less!!
I guess you mean the linear map keeps them in check because it doesnt all of a sudden open full throttle when you dont want it causing a load of boost to bend rods
pump the tyres up, you have less rolling losses, so an "apparent" higher figure (IF) only atw figure is used. Dynojets in the US only quote atw figures, which are pretty much always higher than over here.. Dyno dynamics also only measure at the wheels and factor the number to estimate the fly figure..
dyno's which measure coastdowns are'nt effected as they measure coastdowns and atw and the changes in tyre pressure etc are seen in the change in coastdowns.
Bill, since we're on the subject of dyno results, how would a ramp rate of "inertia" affect results? I was at a RR day recently and a few people expressed surprise at getting lower than expected torque figures. Could that be related to these "inertia" runs? Or are torque figures considered to be at-the-wheels rather than at-the-fly?
dyno dependant thing.
on mine as an example inertia is insufficient load and is'nt realistic, and very quick runs.. which are not like the car would do in the same gear in real world.
I use a ramp rate which loads the car but does'nt hold it so slow as to drive it into extreme temps, as that again is going to give misleading results.. eg died on its arse from heatsoak wont give you a good figure.
inertia runs can be very quick tho... so the cars not settled under load at any point.
how long did the runs take and in what gear for example?
On my car at least the runs were done in 4th. Didn't strike me as particularly quick tho. It was a Dastek dyno if that makes any odds?
heavier rollers than mine... inertia in mine is'nt of much use for power runs unless the cars got so little power it cant manage even ramp rate 1 - lol
I use 5th on LCR's unless they rev >7800rpm which is faster than my rollers bearings are rated too
I prefer to use loaded - consistent on mine
I use 5th on LCR's unless they rev >7800rpm which is faster than my rollers bearings are rated too
I prefer to use loaded - consistent on mine
Last edited:
Similar threads
