Boost numbers with different pulley's???
 

I can't find a Code 3 pulley for my wife's convert so I am about to buy a 181mm pulley/tune from eurocharged for $1000 plus then I need the $200 pulley saver kit from Rob. I have the stage 2 tune from Inmotion and I guess I will still need the high boost Eurocharged tune with the pulley or do I??? I could save $200 by sticking with the Stage 2 from InMotion.

2ND... By my math, the pulleys add boost as follows
155 stock= 14.5 then
178/155= 1.148*14.5= 16.65 psi
181/155= 1.168*14.5= 16.93 psi
185/155= 1.194*14.5= 17.31 psi
My coupe's 65mm C3 pulley = 65mm/78mm = .833 14.5/.833= 17.4 psi

The SC pulley is half the price and doesn't need any pulley saver kits so I want to find someone that will build them!! If not, than do I need to get a new tune or will the IM stage 2 provide enough fuel for the 181??

Thanks,
Blake and Laura

Re: Boost numbers with different pulley's???
 

I think your numbers are off. The 181 is good for around 20psi (mine is) and the 185 is around 22-23psi (from what I've read). Keep in mind, my 20psi reading was taken from the manifold. Recently someone in high standing posted that the numbers taken from the Y-pipe are inflated.

Re: Boost numbers with different pulley's???
 

I believe that you are going to get a variety of responses based on location, elevation for the various pulleys.
I know my boost levels change with the seasons also.

Re: Boost numbers with different pulley's???
 

My C3 65mm on the coupe reads 17.5 psi in the manifold so my math works for that. How does the 181 go up 16.7% in size but make 33% more boost? I just wish I could see the math or reason for it. I wish I could find a used C3 somewhere!

Mine also hits high 7's @91-93 in the 1/8th with street tires and good launch and 1.9 60 ft so I don't mind if it makes less boost I just really don't want to pay $1200 for the same result:( Who will sell me a used C3 pulley???:confused:

Re: Boost numbers with different pulley's???
 

I doubt you'll find one for sale. I dont understand why a company like Needswings or Eurocharged dont start producing them there obviously popular and would sell.

On another note why dont you just get your wife's stock supercharger pulley machined down to 65mm?

John.

Re: Boost numbers with different pulley's???
 

Eurocharged will be selling a supercharger pulley within a month or two :cool:

Re: Boost numbers with different pulley's???
 

One of many pulley size and boost comparo threads.

https://www.crossfireforum.org/forum...85-pulley.html

Cheers,
KrzyFast

Re: Boost numbers with different pulley's???
 

FWIW
Just checked.
16lbs of boost at the top of third gear in the roadster with a 192mm crank pulley.

70 degrees at 4000 ft.

Re: Boost numbers with different pulley's???
 

192mm??? That's a new one to me. You should be around 20+psi with that, unless you have NW manifolds.

And as far as EC building S/C pulleys... it's about time! lol. Thank god someone is stepping up to do them. I know they probably aren't a huge profit item. But, the more pulleys you sell, the more tunes you'll sell...

Blake, I think your math is a good way to take all the variables out (other mods, air temp, altitude, etc). Will you 'need' a tune, no. Will it fine tune it to get the most out of it, yes. Personally, I'd hold out for EC to have a pulley and get a combo deal w/ a tune... just my .02

Re: Boost numbers with different pulley's???
 

my boost gage is mounted in the y pipe and i have logged 19 psi on a 50* day with my c3. as for the pulley kit i had rob build me a kit for the c3 with oem crank pulley. i did this to slow down the idlers and the ease of replacement with napa pulleys. it also enhances the belt wrap around the s/c pulley

Re: Boost numbers with different pulley's???
 

i HAVE tried for years to no avail:( they cant get the teeth right! I have a spare pulley and no use.

Re: Boost numbers with different pulley's???
 

I should hook up a boost gauge someday to see where my car is at when I'm running good times at the track with the C3 pulley. I'm assuming maybe around 18 psi.

Re: Boost numbers with different pulley's???
 

I see 1.4 bars (20psi) top of third gear and 1.5 bars(22psi) at top of fourth gear, sea level, i have 185 pulley, psk, LT's headers and 80mm TB.
Go directly with EC 185 pulley and tune combo plus HE and pump, nothing can beat the 185 pulley with good cooling.

Re: Boost numbers with different pulley's???
 

I assume you've got some fueling mods also. :)

Re: Boost numbers with different pulley's???
 

The C32 has in tank fuel pump and with Jerry tune it didn't need any fuel mod, Afr is good in my car between 12 and 13 at max at 22 psi, and he can also lower it if i want to 11.5, but the 32 engine give his highest power at 13 AFR and it is safe in this engine, you can go to 13.5 and still safe.

Re: Boost numbers with different pulley's???
 

You lucky dog. :)

Re: Boost numbers with different pulley's???
 

Great info, thank you.

Re: Boost numbers with different pulley's???
 

Are those numbers on the dyno or on the street with a wideband?

Re: Boost numbers with different pulley's???
 

on street of course with LM1 wideband(innovate).

Re: Boost numbers with different pulley's???
 

I have the NW remaned intake mani's and y pipe with the boost gauge pulling from mani tube, not y pipe. The gauge reads -1 with car off and 17.5 at WOT so maybe as high as 18.5! Elevation 1200 and 70's I love my SC pulley and would love another one, or if someone can find a machine shop that can shave one. noone in Roanoke, VA can:(