Drock

hi.... i'll list my setup here again..

2005 non-rev, 6MT
Vortech V2, 3.12pulley
600cc DW injectors
walbro pump
Uprev GT MAF
tuned with Uprev
new plugs
autometer boost gauge
Innovate AFR
MD plemum spacer
Berk HFC
Ichiba Y-pipe
Tanabe exhaust

418whp and 349wtq on Dynapack Dyno. approx 8lbs


was just curious.. if im supposed to see full boost under full power in first gear..?

with the 3.12 car is making about 8lbs..
I see the 8lbs of boost, under full throttle no problem in 2nd, 3rd and 4th..

but I cant seem to get full boost in 1st..? im hitting maybe 5-6lbs..?
and I really have to smash the pedal.. to get up there lol..
as you know 1st is very short.. so it reaches redline fast.. and have to change gears..right away

is this normal for 1st gear.. that boost just doesnt have enough time to built up.. my assumption with a SC.. shouldnt make a difference etc..

not sure if its belt slip.. cause it doesnt seem to happen in the other gears..

so im wondering if this is normal for 1st gear.. or if in the end..its just belt slip..?

TopgunZ

I kind of wish i didnt hit full boost in 1st...lol.. Allows you to hook up easier.

Drock

hi...
ok but you are running turbo right..?

the car makes boost in 1st no question.. probably reaches around 5-6lbs...before having to change gears..

it just seems it doesnt make full boost in 1st.. as it does in 2nd,3rd,4th etc..

so im just curious if this is normal for a SC setup... that since 1st gear is so short that it doesnt make the same boost as in 2nd,3rd, 4th.. which reaches about 8lbs undr FT..

str8dum1

iTrader: (11)

you still need to fill the volume of the charge pipes. between that lag and the short time that you are in 1st, its no surprise you dont hit full boost

ranmas2004

Happens to me too. I have a turbo and dont even get a chance to get barely 1 psi in 1st. Its a good thing because you have traction.

djamps

iTrader: (1)

The TB doesn't open fully in 1st gear even with the uprev throttle map. Not sure if it's 'enough' to limit boost, just throwing it out there. You also need to remember the engine is under much less load in 1st gear which at least with turbos, might not be enough to build the boost up.

TopgunZ

A positive displacement will hit peak in first, but thats a whole different story.

nathanwl2004

iTrader: (2)

look up the e-boost2 boost controller. it can be tuned to limit boost for each individual gear. IE 5 psi in first, 7 in second, 14 in third and so on.

binder

iTrader: (8)

technically the SC is tied into rpm of the engine so it shouldn't make a difference but with the very short amount of time in first gear there is going to be a lag between building of pressure and display on the boost gauge. So it's not "lag" as in a turbo system but it's just system lag to display the pressure. It also could be some belt slip since the crank will accelerate at a higher rate in lower gears thus causing a higher chance of the crank pulley moving faster than the belt can hold on to for a short period.

turbo system is completely different for all those that answered based on turbo results. Turbo's build spool based on engine load. Lower gears have less load therefore it will produce less boost in lower gears.

unvmyg35

iTrader: (15)

I agree with binder. I see about 7psi showing on my gauge when im about 6600rpm in 1st gear. I see full boost in all other gears of 11psi.

UMW350Z

iTrader: (18)

I'm usually through the gear so fast after the boost hits, I don't look at the peak. Are you hooking up?