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SC silencer fix?

LSXHP

LSXHP

New member
Was talkin to my friend the other day who has a sc/ss cobalt and he told me they have a mod where u pull the blower off and fill in some pockets that act as silencers for epa reasons. He said they followed instructions from a gtp site as its a mod for the m90 as well. I guess you use quick steel and after that the air becomes super sonic and the effect is a nice sound and supposedly u pick up a couple tenths. I did a search on here and didn't come across anything. Anyone know anything about this??
 


you might as well port it while its off, i do that kind of work, there is a thread on here about it. very reasonable prices, and that port filling is standard in my price. PM me if interested.
 
Well i dont like doing mods without research first, gimme some info on what benifits come with porting the blower and what if any supporting mods are needed. Also this is my daily driver so do u send a ported unit out and then take a core or how does that work?
 
yes, you pay a $50 core charge and i send out a blower case, or if you want the whole supercharger thats fine, just more shipping costs though. Benefits include: louder whine, more efficiency from the supercharger on the outlet side and inlet side, which equate to lower outlet temperatures, which equate to more power. No supporting mods necessary, it is a supporting mod itself. You probably wont notice any seat of pants without doing other mods like an intercooler or headers so that you can drop pulleys, however. Probably wouldnt be my first mod, but its a definite to be done on the way to more power.
 
Well i have the off road 3" DP and zzp pwr log goin in this weekend, next mods were to be a pcm probably from overkill and a 3.4 pulley. possible mods maybe next month im considering rockers and tb. Didnt really plan on doin an intercooler, do u think porting would be benificial with those mods?
 
Others would say no, i say yes. Any drop in temp. on the outlet of the supercharger is going to help. If you pm me maybe i could cut you a deal for being one of my first customers, already have a couple, all that i would ask for a discounted price is a review on how you liked it.
 


here is what he was talking about for sealing the silencer slits:

Picture042.jpg


it makes it louder at a lower boost level, but its not any louder at full boost.

like i was saying before though, the throttle body wont help out all that much at your minimal mod level. the rockers would though. that would be a good choice for a next mod after doing the exhaust.
 
rockers are full of all kinds of win. they add more lift to your cam thus moving more air around in the motor thus making more power. they pull pretty good on the top end :D
 
i love my roller rockers. they quited down the valve train and they seem to pick up rpms good no matter where im at. i can hit it low in second and it picks up pretty good. and pull hard in the 4500 and up range.

i cant speak on the stock modified rockers.
 
Well I would assume the stock modified give the same gain if the ratio is the same. Anyone running the stock modified?
 


Also wondered back to my origional question here so blocking off those silencer ports, that have any gain in pwr or no?
 
LSXHP said:
Well I would assume the stock modified give the same gain if the ratio is the same. Anyone running the stock modified?
Click to expand...

the stock modified wont perform as well as roller rockers because of the fact that they arent roller rockers, but with rollers you pay more and need to change valve springs if you go over 1.8:1.

LSXHP said:
Also wondered back to my origional question here so blocking off those silencer ports, that have any gain in pwr or no?
Click to expand...

zero gain in power. sound gain only.
 
LSXHP said:
Well I would assume the stock modified give the same gain if the ratio is the same. Anyone running the stock modified?
Click to expand...

It wouldn't be as efficient as the roller rockers...

LSXHP said:
Also wondered back to my origional question here so blocking off those silencer ports, that have any gain in pwr or no?
Click to expand...

Blocking off the ports gives you no gain in power, just sound...it is when you hog out the "V" and the inlet of the blower is where you gain your power at.
 
Bio248 said:
the stock modified wont perform as well as roller rockers because of the fact that they arent roller rockers, but with rollers you pay more and need to change valve springs if you go over 1.8:1.



zero gain in power. sound gain only.
Click to expand...


The stock modified rockers from ZZP do not require different vavle train parts, they say they work fine with all the stock stuff and there 1.9:1.
What is the stock ratio 1.5 or 1.6?

As for the blower I guess I wont bother with those ports then....unless I decide to just have it ported...
 


LSXHP said:
The stock modified rockers from ZZP do not require different vavle train parts, they say they work fine with all the stock stuff and there 1.9:1.
What is the stock ratio 1.5 or 1.6?

As for the blower I guess I wont bother with those ports then....unless I decide to just have it ported...
Click to expand...

i agree. i run modified stock rockers on my car with stock valve springs. rollers you will need higher strength ones. the stock ratio is 1.6.
 
Bio248 said:
the stock modified wont perform as well as roller rockers because of the fact that they arent roller rockers, but with rollers you pay more and need to change valve springs if you go over 1.8:1.
Click to expand...

He comes from the LSX world where roller rockers aren't all that. Like I've been trying to tell you guys... Rollers are pretty much a waste. If you bother to look at how the tip on the stamped contacts the valve tip as it goes through its motion, you understand this.

LSXHP, go for L76 springs (from the G8 GT engine, you can get them cheap at your local dealer) with 1.9 modified stock rockers. The L76 springs are better than stocks, but not harsh on the valve train like aftermarket springs nor are they prone to failure like comp cams springs.
 
again ill say i love my rollers :D

if there such a waste why do people, even when keeping the same ration, go to rollers with motor builds?

they consume less energy, usally lighter, thus a free'er reving valve train.

in no way are they a waste especially when your gonna pay close to the same price.
 
blowfishRus6 said:
again ill say i love my rollers :D
Click to expand...

Have you had a car without rollers just modified stock 1.8s? I love my 1.9s too. Not a very empirical comparison.

blowfishRus6 said:
if there such a waste why do people, even when keeping the same ration, go to rollers with motor builds?
Click to expand...

Not knowing better? Bragging rights? On some engines it can make a difference if the stock setup used a really horrible rocker design. Ours, like the LSx engines, is very good so you see little to no gains. There are a lot of dyno runs out there testing on LSx engines that use roller vs modified stock, same ratio. There is no difference within the acceptable margin for error of that dyno.

blowfishRus6 said:
they consume less energy, usally lighter, thus a free'er reving valve train.
Click to expand...

In theory, it's good. But like I said the stock setup was designed to achieve this anyway without the added complexity (and cost) of a roller tip. They're just something fancy that the vendors can charge more for that people seem to want.
 
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