which wastegate?

[stealthy]

you guys think a 38mm wastegate is gonna be too small for 400-450whp? or would a 40-46mm be better? idk...just need some input....

 

[--<EM1>--]

id go with the larger one. are there perimeters for the springs in the wg for lbs? 40-46mm might have lets say a 12psi spring, while youre tuned to only 10 psi.

im confused about wastegates.

 

[slowhatch]

i'd go with a bigger one to be safe like a tial 44mm. if it matters my cousin was running 320whp with a 38mm.

 

[ryanM]

i plan to push 350-400 with a 38mm

 

[mike@synapse]

a wastegate decision isnt really based on power goals its more based on the lowest amount of boost you want to run with a certain turbo and engine setup. larger gates can exhaust more gases than smaller wastegates. also some manifolds are better at exhausting gases through wastegates than others so there are a lot of factors in deciding what size wastegate to run. what turbo/manifold/engine setup are you running?

if you want to run 300whp or less and then on race day want to make 400whp then maybe you want to run a 44mm gate but for the average user 38mm gates work fine.

 

[sohclubkid]

i had the same question... glad to find some light on the answer.

but lets say i want to run 10psi as my low boost setting, but 25 as my high... i would just get a 10 psi spring and keep it i there even when im pushing 25psi?

 

[Jason-]

I'm confused. I thought I knew about wastegates, but I guess not. :/

-Jason

 

[ryan89crx]

38mm will be fine at that power level

 

[ryanM]

i had the same question... glad to find some light on the answer.

but lets say i want to run 10psi as my low boost setting, but 25 as my high... i would just get a 10 psi spring and keep it i there even when im pushing 25psi?

the spring in your wastegate is just the LOWEST boost you can run, you can go higher with a boost controller.

 

[Shiznit]

id go with a 44mm just incase of boost creep issues, BUT 38mm will be fine

 

[stealthy]

its a built gsr with a gt35r.....to hit 425ish whp im guessing its only gonna take 16-18psi.....but daily driving im gonna be around 325whp on low boost. the reason i ask is bc of the big price dif between a 38mm and 44/46mm

 

[mike@synapse]

to get down as low as 325whp i doubt even a 44mm wastegate will allow enough exhaust gases by, and the 38 definately wont do it.

 

[Shiznit]

38mm is definetely big enough for 325. i have a friend putting down 527whp with a 44mm wastegate

 

[ryan89crx]

to get down as low as 325whp i doubt even a 44mm wastegate will allow enough exhaust gases by, and the 38 definately wont do it.

sure it will

the 405hp Vitara sohc sedan is running a single 38mm knockoff with no spike or creep issues, and thats at 25psi

 

[mike@synapse]

how can you compare, thats at 25psi, and on a d series

now try running 7! on a bseries with a gt35r.

u guys are thinking backwards about the wastegate sizing. its not about how much power they are making. its about how little power you want to make.

 

[Shiznit]

i was thinking about the power he wants to make. he wants 450ish, and a 44mm wastegate would handle that just fine

 

[mike@synapse]

he also want 325 to daily drive

 

[Shiznit]

now youre just confusing me lol

 

[mike@synapse]

a small gate is fine at high boost. you dont need to exhaust much gases to maintain turbine speed.

but to maintain very low turbine speeds on the larger turbos u need to exhaust more gases around the turbo. that is why you need a larger wastegate.

 

[stealthy]

i think ive decided on a 48mm blaast wg.....only $230.....