i have a '91 civic crx si with a jackson racing supercharger. lately the supercharger has been making a rather funny noise. the sound is rather like there's debris being sucked in or something. a sandy noise. and this sandy noise seems to occur more often when i shift early and gas it hard. say a floored gas pedal in 4th at low rpms. anybody have an idea on what the problem is?

a list of mods off the top of my head:
- jackson racing supercharger
- smaller diameter supercharger pulley, raises maximum boost to around 9psi
- dc sports header
- k&n filter
- 450cc injectors from a mitsubitshi eclipse turbo
- 1 step colder spark plugs (stock plugs for an audi 9000 turbo, I think)
- removed the rising rate fuel pressure regulator from the jrsc setup (modified computer program instead)
- tokico blue shocks
- some no-name adjustable springs
- acura gsr '95 wheels
- flowmaster muffler
- misc computer program mods

 

off topic, but...


have you ever ran your car at the track? im curious to see what people are running with jrsc's.

 

detonation maybe? try running some higher octane gas or retarding your timing

 

Has the charger has been in use for a while?

I've heard mention of shaft play on well used/abused units. That may eventually lead to rotor-to-casing interference. You might want to search/inquire on http://www.theoldone.com, Larry Widmer knows the in's and out's of the Eaton blowers.

Here are excerpts from a recent post about a CRX/JRSC/noise problem:
poster:
After installing a Jackson Racing supercharger on my '90 CRX, I have been experiencing a "rubbing" / vibrating noise when the engine is under heavy load (in boost and hard acceleration). I do not lose any power when this happens. The noise seems to be coming from the pulley area and logic would seem to point towards a pulley rubbing as the engine rotates backwards. I have been unable to find any signs of the rubbing and have installed poly motor bushings. These seem to help, but do not eliminate the issue completely. In addition to myself, I have had several performance shops look at this without finding the issue. I am afraid that I am going to find out the hard way when something finally breaks... Has anyone had a similar problem? I am leaning towards the pulley bushings...??

TOO's responses:
If the blower drive shaft has been pushed into the case housing, it'll make a lot of noise...and it'll be destroying the pin-drive inside.

Does it make noise at idle and is it losing any oil from the shaft seal? You can also get a couple large screwdrivers and try to leverage the pulley (and shaft) outward some. If it moves, the drive is "hurt".

 

from some other threads that i read, the problem seems to be detonation. and i talked to my brother-in-law (it was a gift from him), and it seems like this isn't a new issue. he tried retarding the timing and he said if i played around with it i could probably eliminate it. but as long i ease off the gas when it happens, i should be fine. man the car is quick tho. i just put new tires on it and it is fast. thanks for all the help fellas. 'preciate it.

 

Cool, better detonation that you can tune out than the scenario I cut-n-pasted above.

Out of curiosity, are you using an Zdyne for engine management? Reason I ask, I know someone who may do a similar setup. Just wondering if you have a base map they could look at.

 

check here:
http://www.geocities.com/civic_fi/zdyne/zdyne.html
HTH
chris

 

try posting this at theoldone.com under ask TOO!

 

XrcR6, i don't believe my brother-in-law used a commercial zdyne. he thought that they were way over priced and that he could probably do most of the same things on his own. so he did. here are some of the computer program mods he made:

- adjusted fuel maps for big injectors
- added maps for handling supercharger
- fixed a couple of minor bugs found in the stock code
- Check engine light doubles as boost indicator

not sure what else. all i gotta say is that the car is fast.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ITSTOCK &raquo;</TD></TR><TR><TD CLASS="quote">off topic, but...have you ever ran your car at the track? im curious to see what people are running with jrsc's.</TD></TR></TABLE>

i gotta a friend here on h-t (civic2003) 93 HB Si GsR Jrsc'ed all stock with stock i/h/e 13.4..stock everything with 6 lbs boost 2.3 60ft