I have an SOT supercharger kit that has ben installed for about a year and a half and 20,000 miles. I am happy with the kit and have no signifcant problems.

There is one issue that I am trying to figure out. Other kit owners get about 6 psi boost from the stock pulley but I get 10-11 psi. I have both an OEM MAP sensor and a Zeitronix boost sensor that agree on this higher boost.

I do not think my blower/intake set up is actually generating more boost than other SOT kits. If the air flow were normal with 10 psi boost, I would expect maybe 350 whp or more, but I am sure my whp is not that high, probably more like 300 whp.

As far as I can see there is no reason for my SC to generate more boost that any other SOT SC. What I think is happening is that there is some type of restriction downstream from the MAP/Zeitronix sensor location that is choking flow and raising boost. I am running OEM header, a 63mm Invidia test pipe and a 70 mm Invidia single so I do not think the exhaust is the problem.

If there is a restriction, I would like to fix it so the boost is not higher than it needs to be for normal flow.

Does anyone have an idea as to what might be causing the higher boost?

 

just some ideas...

valve adjustment maybe
check the actual diameter of the pullies; you never know
possibly vtec not kicking in for the added flow; either on one cam or the solinoid

just some ideas, but this sounds like a tuff one. Have you talked with SOT about this?

Ryan

 

OEM header DOES choke airflow and weighs SOO MUCH haha

-63mm test pipe is only like a few mm larger then stock.

-your perfect on the 70mm exhaust.

i bet if you bought aftermarket headers and switched to a 70mm test pipe you will have much better air-flow.

 

No such thing as too much boost!!!!

Something doesnt seem right here, for that amount of boost you should be well over 300hp.

Maybe the other guys will chime in here soon with that kit. Seeing as I am dropping mine off Monday to have this kit installed i would like to know whats going on with your setup as well.

 

A freind was running 10PSI with a ATI head unit in a otherwise stock WS6 and we added a cam and headers which dropped it down to 7psi.

There is something choking the flow if the pulley is correct.

 

superchargers flow a constant amount of air in relation to the engine's rpm. back pressure plays a huge part in how much pressure you see in the manifold. changes in exhaust will easily raise or lower the boost pressure even though the total air flow stays constant.

with the SOT kit 6 psi should be around 320ish whp, camuman's car dyno'd 350whp at 8psi, haven't dyno'd it yet on 9.5psi. he's got berk headers, test pipe, and asura 3" dual so the exhaust is pretty free flowing. 100% stock exhaust and it would probably be a pound or two higher. he's also at sea level, any higher in altitude and the boost would be lower.

the only real differences between your setup and his that I can tell from your sig is the headers and the test pipe, that could be why you're seeing more boost. mark will post in here before too long I'm sure, he may have a better idea.

 

neptuner.

Has your boost always been this hi.....



I remember you asking about it at TPGR SESM last year but I don

 

In a way I hope you do infact had the 145mm crank.


It will show the reliability of the blower/kit even with the 145mm pulley.
You have had your kit on almost as long as William has. 1.5 years with a 145mm crank


If you have the 145mm you absolutely need to get up to Huntsville so we can get it on the dyno and get some numbers It will be free for you even if I must pay for it myself..

 

now thats an offer you should not refuse

 

Wow, thanks for the great responses.

Checked valve clearances - they were OK. Adjusted a little with no change in boost
Pulley diameter - Checked crank pulley and was about 125mm, same as regular 6 psi kit.
VTEC - definitely working. Kicks in at 6000 and boost drops by 1 psi then increases.

Others are running similar test pipes or OEM cats and do not see this level of boost. I think a 63mm test pipe should offer very little resistance for my kind of SC. I do have a Rick's header on the way but I am not expecting much of a change to boost. I believe WLaurent is running the OEM header with this kit and not getting this level of boost.