whackassfawker

I have a greddy kit on a semi built b18c5 running 14psi. Hondata management, 680's, walbro, 3'' downpipe and exhaust. If I floor the car in first I get 13psi, second stays the same, but by third gear it spikes to 17 then back to 14. If I keep on the gas I run 14 psi always. However if I'm going say 50mph in third and then floor it the boost will go past 20psi. I'm using a turbosmart mbc, have also tried the ball and spring style to no avail. Is it worth buying a ebc? What else can I do? My vac reference is from a 1/4'' fuel line from the intake manifold and it's a short as possible. This problem is annoying because I can't pull in any gear higher than 2nd. Please help.

curacaocrx

Hey ,
i heard that the boost spike's can be less if you have a larger wastegate.
so i guess a large external wastegate would help.

self.one

i'd have to agree on that a larger wastegate would solve your problems, but i'm guessing you have the stock turbo from the greddy kit, which is internally gated, so that would have to be the source to your spiking,... which means that upgrading to a bigger w/g is out of the question....

whackassfawker

exactly what is involved with wastegate porting? Do you just start removing material?

whackassfawker

bump

Bspec18

I had a buddy w/ similar situation, He just went with an external WG and no more problems

auto moto

ya i have an external wg and no boost spiking what so ever. and its a 6year old delta II gate and still running strong

whackassfawker

How is it that people run 22psi in dsm's on 16g turbo's. I can't hold 14psi.

auto moto

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by whackassfawker &raquo;</TD></TR><TR><TD CLASS="quote">How is it that people run 22psi in dsm's on 16g turbo's. I can't hold 14psi.</TD></TR></TABLE>because they have a solid block like a hot rod oposed to where we need to sleeve our blocks because of sleve flex, there are a lot of other things to but thats why we cant run a lot of boost ..... steel block= lots of boost

whackassfawker

how does the turbo hold that boost though?

toolowsol

I believe their ecu acts as a electronic boost controller

auto moto

ya, i think there ECU has a built in boost retard, map, and boost/feul reg. to make the boost stay at its set position.