manifold issues

kwik enquiry to the SX CA18 masses

i ahve a top mount manifold(ala spagetti that runns forever piping) and i have been told to ditch it as it is causing un nessary LAG(on a t28...starts boosting at about late 4k rpm 😢
i know the mods i have on the engine and the mods done to the turbo itself.....it should be kicking ALOT sooner???and the kick alos isnt that strong...very weak.....
been told a kwik and easy solution is changing to the stock manifold(my aim with car is about 330bhp..give or take)....
is it possible with teh std manifold???
but i dont want bottom mount...i like my turbo on top.....
ideas??
(ws thinking of just modding the std manifold with some extra piping for top mount? 😕

Hey turbophonic... I've heard that a log manifold works pretty well and it's actually a bit cheaper than the one you have... It's like the standard manifold but the piping is straight to the point and flows nicely...

This is a down-mount though...

I fitted my tubular manifold and the spool up time was no different. I definately flowed more at high rpm though.

I was one of the guys that should lag would be great because the air needs to travel farther to get to the turbo, this is not the case when the air is moving at about 200km/h.

Also you are talking about boost thresh-hold not lag, the manifold will have no affect on the boost thresh-hold.

200SXSilviaSavage wrote:

Hey turbophonic... I've heard that a log manifold works pretty well and it's actually a bit cheaper than the one you have... It's like the standard manifold but the piping is straight to the point and flows nicely...

This is a down-mount though...

hey man...u just confirmed advice i got from a buddy working at Powerflow.siad to cut all the fancy schmacy stuff and just go log/block manifold 😈 ,doesnt look "bling" but spools gases kwiker than a hobo at all u can eat beans fest! 😉

i cud be wrong 😕 ,but it looks almost easy enuff to give it a DIY try? 😕

u just confirmed advice i got from a buddy working at Powerflow.siad to cut all the fancy schmacy stuff and just go log/block manifold ,doesnt look "bling" but spools gases kwiker than a hobo at all u can eat beans fest!

Wonder why any car that makes decent power uses a tubular manifold with equal length runner ..... hmmm 😕 . Its basic physics why a tubular manifold should be used.

Gary57 wrote:

u just confirmed advice i got from a buddy working at Powerflow.siad to cut all the fancy schmacy stuff and just go log/block manifold ,doesnt look "bling" but spools gases kwiker than a hobo at all u can eat beans fest!

Wonder why any car that makes decent power uses a tubular manifold with equal length runner ..... hmmm 😕 . Its basic physics why a tubular manifold should be used.

i hear you, but i already have a equal length tubular made by TNT in jhb, on the car at the moment....and the car just has SUPER lag...i only get to about 0.5 bar foot flat at 5000rpm.....and she's still busy waking up...so full boost(1.0bar) will only be reached at about 7000rpm????crazyness!!?
i was told its the design and length of my current tubular that is hampering my spool time?...and i mean..not like im runing a T4...its a T28??should a T28 really be spooling only after 4500rpm??

on my t28 i get 0.8 about 4193rpm

rat wrote:

on my t28 i get 0.8 about 4193rpm

hmmm - thats a rather precise measurement. you got a nice tool then??? 😮 😮 😮

havent had any complaints

lag could be caused by alot of things, plumbing diameter, intercooler sizing, etc.... f**ked turbo, faulty wastegate, how bout more details and mayve some pice of the installation... anyway doubt that your lag is caused by your manifold..

this is a pic of the manifold on the car...

heres another angle...

.. car is running 50mm boost piping, thru a 160mm x 600mm intercooler, length of run in pic below.

as far as my external wastegate goes, no issues with it,i had a look at it when it was off teh car,in good shape.
the engine is a new rebuild with less than 1500km on it, turbo is also a rebuild with less than 500km on it.all gaskets are new.so other than manifold length being the cause of lag.....i cant see anything,umless u see somthing or know of somthing i havent thought of yet? 😕

Take the vacuum pipe going to the actuator off and then go for a drive, obviously block the pipe, and see if there is any difference in lag.

Gary57 wrote:

Take the vacuum pipe going to the actuator off and then go for a drive, obviously block the pipe, and see if there is any difference in lag.

cool will give it a try.....
wont it cause "overboost" though? 😕

Yes it will cause over boost but will eliminate wastegate creep, it will give you the fastest spool up the turbo is capable of.