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ie3.0
07-27-2011, 07:57 PM
Hey guys,
i purchased the Tomei M7960 on frsports and got it tuned.

car made 358.9 hp @ 18psi. on a dynodynamic. with C.F. 1.0

Good power, but when it actually comes to driving, i feel the car get no power on 1st gear, and boost kicks in late .

here is the mods on the motor:

S14 SR20DET (75000km)
Greddy Vspec FMIC
Turbo back exhaust,
Nistune
Apexi AVC-R
warlboro 255lph
Tomei RAS
Tomei 740cc injectors
Tomei m7960 Turbo.
Stock Head & bottom.

daily driving @ 1bar

Here is the dyno graph
http://a1.sphotos.ak.fbcdn.net/hphotos-ak-ash4/283902_10150372987190968_505915967_10059797_671957 8_n.jpg

this is the first time i have a "big" turbo , i feel the boost kicks in very slow (compare to a stock turbo),
my question is , what can i do to get more response?
is it the Tune problem? or the Tomei turbo is supposed to be like that? (its a 20G turbo, identical to a Td06 20g mitsu turbo i think)

im going to do Splitfire coilpack, tomei exhaust mani, camshafts soon, just wanna see what kind of options i have to make this turbo spool quicker.
video of the dyno tuning
‪s14 Tomei m7960 Turbo Dyno 2‬‏ - YouTube (http://www.youtube.com/watch?v=0RvHKrj-1Vc)

any comments will be appriciatd guys, thanks in advance.

Vic

ie3.0
07-27-2011, 08:00 PM
p.s., i have an exhaust leak between turbo elbow and downpipe, i will fix that soon. but im not sure if back pressure (away from the turbine) affects the response by that much, im kinda runnig out of my ideas now. please help thanks!

4x4le
07-28-2011, 01:01 AM
Perhaps more tuning could take place in the lower rpm range. Whats really odd is how low your revving your engine. Are you sure the dynos rpm and vehicles rpm were syncronised?

sent from my rooted thunderbolt

TheRealSy90
07-28-2011, 03:26 AM
Cams cams cams.

4x4le
07-28-2011, 04:47 AM
Meh at the cams.
That turbo really isnt that big, and cams arnt going to make it spool quicker, its going to hurt it if anything. Sure the powerband will be shifted but i was making more than this on a 2871 on stock cams and power climbed untill rev limit (8k at the time i believe).
Something is wrong with the graph, there is no way he only has a 1500rpm usable range, its got to rev higher.

sent from my rooted thunderbolt

ie3.0
07-28-2011, 07:39 PM
^ thanks alot about the comments, there is a factor that when we doing the dyno tuning, the fan was broken( the one we put infornt of the car). so maybe heat killed some of the TQ its like the fmic is not working.
and yea, i told my tuner that i dont wann rev pass 7k on my stock head, (cuz the tendency of poping rocker arms on the stock SR head)
i will do cams, valves etc and make it capable of reving to 8-9k next year so i can get more usable powerband.
and maybe its because the journal bearing turbo itself? Tomei should at least make it twin scroll...

cbcm2435
08-27-2012, 07:15 PM
are you still using the stock MAF? i didnt see one on the list of things you did