Speeds going thru gears

C

cobra10

New Member
Hi,

Got a query, cars is running fine (I think) on standard boost ie 0.7 bar but wondering if the speeds I'm hitting thru the gears are correct.

In 2nd I get to 50 ish at roughly 6500rpm and around 80 in 3rd. I dont push it any faster because I run out of road and wind down and also I dont drive like this all the time, just want to see what she can do.

Is this about right? I hear stories of people hitting 70 in 2nd but wondering if thats with boost turned up? Ive got a G Reddy II controller in but Ive switched it off for time being to get car running right before I go tinkering.

Cheers
 
gtir_pimp

gtir_pimp

New Member
what you are hitting sounds right. boost wont make any difference what speed you hit in the gears as it depend on what revs you hit before you change gear. i have hit 70mph in 2nd but that was like 7500rpm! i wont be doing that again as it didnt sound healthy. some people have hit 130mph in 3rd gear before because they have fitted white dials which alot people cock up when fitting! my mate has them in his and on idle he is doing 7000rpm!!
 
olliecast

olliecast

Active Member
Hi matey,

So long as your engine is healthy then i wouldn`t really worry about it mate.
TBH i wouldn`t know about i`m doing in each gear as i tend to be concentrating about the next corner approaching, lol

Just enjoy it until you first experience issues :thumbsup::-D

Cheers,
ollie
 
C

cobra10

New Member
ok fair enough i do like a bit of the old lead foot, just not all the time, drove car up from midlands when i got it, got 300 miles from full tank, those days are well gone lol
 
DanDud

DanDud

Member
According to my speedo (which reads the same as a TomTom - dont know how accurate they are though) :

At 7k in each gear:
1st - 30
2nd - 60
3rd - 90
4th - 120
5th - 150 but i dont know what the tomtom said, but does that seem about right?

All done on tracks and not public roads btw
 
PobodY

PobodY

Moderators
Staff member
Yeah... I think I'm more like:
1st - 20
2nd - 40
3rd - 60
4th - 90
5th -120 (Never got there)
But to be honest, I don't really pay attention to the speedo... I'm watching the boost gauge and the tacho (when it points straight up and the boost reads ~1bar it's time for a new gear).

That'd be an RB gearbox for you.
 
Fast Guy

Fast Guy

Moderators
Staff member
Changing at 7500rpm with gear ratios of 3.285, 1.850, 1.272, 0.954, 0.740 a final drive of 4.125 and a tyre circumference based on a 215/40/16 an RA box............................

Top Gear gives 22.192 MPH/1000 RPM and a top speed of 166.442 MPH at 7500 RPM
Engine speeds in top gear:-
30 MPH = 1352 RPM 40 MPH = 1802 RPM 50 MPH = 2253 RPM 60 MPH = 2704 RPM
70 MPH = 3154 RPM 80 MPH = 3605 RPM 90 MPH = 4055 RPM 100 MPH = 4506 RPM
Top Speed in 1 gear = 37.494 MPH
And changes into 2 gear at 4224 RPM dropping 3276 RPM
Top Speed in 2 gear = 66.577 MPH
And changes into 3 gear at 5157 RPM dropping 2343 RPM
Top Speed in 3 gear = 96.829 MPH
And changes into 4 gear at 5625 RPM dropping 1875 RPM
Top Speed in 4 gear = 129.106 MPH
And changes into 5 gear at 5818 RPM dropping 1682 RPM
Top Speed in 5 gear = 166.442 MPH


An RB box on the same tyres should give you

Top Gear gives 18.027 MPH/1000 RPM and a top speed of 135.200 MPH at 7500 RPM
Engine speeds in top gear:-
30 MPH = 1664 RPM 40 MPH = 2219 RPM 50 MPH = 2774 RPM 60 MPH = 3328 RPM
70 MPH = 3883 RPM 80 MPH = 4438 RPM 90 MPH = 4993 RPM 100 MPH = 5547 RPM
Top Speed in 1 gear = 40.159 MPH
And changes into 2 gear at 5123 RPM dropping 2377 RPM
Top Speed in 2 gear = 58.791 MPH
And changes into 3 gear at 5918 RPM dropping 1582 RPM
Top Speed in 3 gear = 74.511 MPH
And changes into 4 gear at 5771 RPM dropping 1729 RPM
Top Speed in 4 gear = 96.829 MPH
And changes into 5 gear at 5371 RPM dropping 2129 RPM
Top Speed in 5 gear = 135.200 MPH

I have smaller tyres so don't reach those speeds, but according to datron I'm still very short at 123mph:? maybe I have a Nismo box? I heard they were only good for 120ish. Or maybe GPS is shite and I am doing the speed on the speedo:lol:
 
C

cobra10

New Member
had car on dyno at hypertech yest and found a few probs on it which was, according to duncan, hindering performance.

fuel pressure aint high enough and back brakes are binding badly, so hopefully after i get what was advised fixed the bhp might go back up, sitting at a pitiful 190 standard, again hoping because of the probs already mentioned
 
C

cobra10

New Member
he advised to upgrade to walbro 255 if not already in and get a fsc or fse fuel pressure regulator and set it to 3 bar

ive got a mate thats had pulsars before and knows a bit and duncan trusts him so we will whap off the wheels and break down and put back together and put in some copper grease? and see what happens from there, and obviously change pads because i know the front ones are gone so might as well do them all
 
Fast Guy

Fast Guy

Moderators
Staff member
I'd check the voltage at the fuel pump first. Lack of voltage will give lack of fuel. My standard pump coped OK with 1bar, I only replaced it for the sake of it.
I would fit the walbro anyway, but you shouldn't need to change the fpr unless it's faulty. Apparantly fse ones give alot of problems.
 
C

cobra10

New Member
kl, will do, what sort of voltage should i be getting? assuming there will be a how to guide on the forum somewhere ;-);-);-)
 
PobodY

PobodY

Moderators
Staff member
Yeah - get the pump flowing first. You don't need the after-market FPR if the pump is providing enough flow and the mapping is right for your boost level and injectors... and if it's still not flowing enough go for bigger injectors instead of upping the pressure more; why make them work harder than they're mean to?
 
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