94EGZI

Im just curious. i just bought a .25bar small yellow spring which is almost 4lbs but it still spikes up to 10-12 at wot. vacuum line is fine its hooked up to the turbo so idk? just let me know what u think

.dave

Can you provide more information about your setup? Engine, turbo/size, exhaust manifold, etc.

Schister66

Which turbo? Manifold? Wastegate? Vac line size to wastegate?

94EGZI

this is what i got. .42 trim turbo knockoff tial wastegate with real tial yellow spring in it. Used the rubber fuel line from autozone for the vacuum hook up to the side of the wastegate to the compressor side of the turbo right? is there anyway i can turn it done or what? what the hell is the hole on top of the wastegate for in the first place? have anything to do with my problem?

HiProfile

10psi on a $15 gauge, or 10psi on your datalogs?

Also that manifold has the worst WG placement of all honda types. Cyl #2 has to hook a 140* turn to exit it, #3 has to go 90* and OVER the collector, and #4 has to go a farther distance than #2 & #3 combined.

The only other thing I can guess is that, like MANY knockoff WG's, your diaphragm is ruined. Many have the rubber one that's paper-thin right before the fat lip - any mis-alignment and it will bind & tear. A hole in your WG will leak the boost right past it w/o lifting the WG's valve, meaning spike/overboost. Given the fact it was opened by the user, this is the most likely reason.

importguy21

theres a easy way to solve this buy a tial wastegate and call it a day, itll save you a lot of time and trouble in the long run

SD_Lurker

iTrader: (4)

That still won't resolve his issue..Wastegate placement on that manifold is horrendous to say the least.

accord_raffi

ya i'm not liking that position for the wastegate...too bad money is so hard to make but so easy to spend

94EGZI

whats with the hole on top? does it need to be plugged or something

nevermind its for ebc.. well any suggestions on what i can do to help out? not going out and getting a new mani and wastegate etc.. anything i can do to these things i have now? or no


Modified by 94EGZI at 11:59 AM 11/9/2008

Tippyman

Open it up and see if the diaphragm is torn or "dented". If it is, I'd trash the whole damn thing and buy a used tial.

If that doesn't fix your problem, I'd buy a new mani. Although I can't see the mani being THAT big of a spiking problem at such low boost levels.

HiProfile

With a .42/.48 50trim T3 and a 2.25" DP, it shouldn't have a big issue controllng boost like it would with a stg5 .82ar T3 turbine. The main issue - with 3psi, you need to route a LOT of exhaust through the WG.

For reference, I have a HMT topmount, 3" downpipe, knockoff 35mm WG with 3psi spring, and t3/t04b s-trim with .48ar stg1 housing - but <U>perfect WG placement</U>. My datalogs show it holding boost at 2.9-3.1psi all the way to redline. The WG is even recirculated, so a CDM wastegate will have no issues holding low boost, given good placement on the manifold & untorn diaphragm.

Tippyman

You know you're right...

I didn't think about that, but the LOWER the boost level, the MORE efficient the manifold has to be at getting pressure out of there.

94EGZI

Well looks like im gona look for another manifold cuz the wg is fine inside. no damage or nothing. probably just the placement. too bad i couldnt just mount a new flange on this manifold temporaly in the middle. ill probably just leave it be for now till i can afford a new mani. thanks for all the input guys makes alot of sense

94EGZI

would this mani be better so i could do low boost?

accord_raffi

that's a lil better than the one you have but try to find something with a wastegate flange more in the middle

94EGZI

well im working on saving for this..
Ill just have to be careful with my car till i can get it controlled.. thanks again

Silva Bullit DC4

Yes, I totally agree with the above pic. Thats a "Mini Ram", it has short runners for great spool maximization, and its tubular, so it will flow better than a conventional cast or log manifold. Kinda like the best of both worlds, and most importantly, great wastegate placement.

This will also be my mani of choice on my upcoming LS/VTEC rebuild, BTW.

accord_raffi

that's a very nice manifold there.