Underboost to Overboost to...

[matt325is]

Hopefully I have found the happy medium. Some of you might know my catalytic converter clogged, and left me to build my 3" exhaust. I was underboosting because my wastegate was opening all the time to try to ease flow (nice the CAT was clogged).

When I build my 3" exhaust it was so free-flowing that my wastegate could not flow enough air around the turbo to keep the boost level down, so I was achieving very high boost levels (21psi was the max I saw). Then I blew an exhaust manifold gasket, so while replacing that, I did some things to my wastegate adapter that might help flow more air.

Here is a picture of the old wastegate adapter, the hole was only 1".




I cut it off, drilled another hole in the other side of the manifold adapter, and welded 2 pipes to connect to the wastegate. I tried to give it the best flow possible with the space alotted. Somehow I got everything to fit.



Hopefully this flows enough, if not, I might need a bigger wastegate. Or maybe adding a muffler might give it enough backpressure to not overboost.

Here is what my setup looks like (I painted the adapter after I took this photo with VHT Flameproof Coating 1500 degree (flat aluminum). I will probably route the wastegate pipe back into the exhaust sometime.



Oh, and by the way, 21psi is NUTS. 0-100 REALLY quick!

matt

[arnib]

Sweet! 8)

I just love your car! :)

[Schnell 318]

i think it is time to upgrade to a larger wastgate. that deltagate is what 35mm? i think you should get a good 40mm wastgate, that would help out alot.

do you have that gate plumbed back in or any kind of dump tube? that also might be a good addition

[skat 325is]

Whoa, nice man, i hope you have a boost controller...working with that wastegate isnt gonna be fun...ask me how i know. :P

[matt325is]

Yeah, I have a manual boost controller. My wastegate used to be plumbed back into the exhaut on the 2.5" setup. Right now its dumping into the atmosphere. I will probably route it back into the exhaust when I get time. I'm running out of steam right now, been up for 24 hours, and will be up for another 12 or 13... Might do it tomorrow or something.

matt

[rwh11385]

Re: Underboost to Overboost to...

Oh, and by the way, 21psi is NUTS. 0-100 REALLY quick!

matt

21# OF BOOST?!? :shock:

holy fuck. .... :twisted:

[Erick]

you know a 0-100 is quick when you dont have to bother timing it :)

can't wait to see the results Matt.

[KenC]

21!?
I rode in it when it was at 16 and we hit 130 in about 10 seconds.

[325is_MadBimmer]

21!?
I rode in it when it was at 16 and we hit 130 in about 10 seconds.

mph or kmh? What kind of power is expected with a bout 20 psi, because thats what i am planning on getting i nthe "future"

[Jand3rson]

21!?
I rode in it when it was at 16 and we hit 130 in about 10 seconds.

mph or kmh?

That would be mph. Last I checked, we were still in the US.

[AndrewBird]

21!?
I rode in it when it was at 16 and we hit 130 in about 10 seconds.

Ditto. That was FUN.

Andrew

[Wes325]

21!?
I rode in it when it was at 16 and we hit 130 in about 10 seconds.

mph or kmh?

That would be mph. Last I checked, we were still in the US.

________
Suzuki SV650

[Erick]

21!?
I rode in it when it was at 16 and we hit 130 in about 10 seconds.

So.... 0-200 km/h in 10 seconds.....

.....wow.

[Jay Stock E30]

how does the wase gate sound venting to the atmostphere?

[e30Matt]

how does the wase gate sound venting to the atmostphere?

My guess would be a loud rushing sound at high boost levels.