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Cams and CA smog

8K views 182 replies 2 participants last post by  mixxbreed 
G
#1 ·
Hi all,

I am considering a new cam, roller rockers and a mild port job on my 96 SS. I am, however, concerned about passing smog here in the Socialist State of California


Is anyone in CA running a new cam and passing smog? I don't mean barely passing or passing through a friend, I mean passing.

If so, please tell me the mods you made and part numbers if you remember. This is a mod I probably will do in the next several months. After I get my new Neal TC from Dan!

Thanks,
Mike
96 BBB
 
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1
G
#2 ·
On a stock displacement motor WITH CATS, you can pass with a surprisingly wild setup (out the tailpipes at least).

For instance, Marc McGovern on his 96 SS with 396 LT4 and 846 cam passed.

Also, Joe Watring in LA has passed emissions on his car with ported heads and LT4 HOT cam.

If you run anything close to a streetable cam in a stock displacement motor, tune it right, and keep the cats you should be able to pass.

Ed
 
G
#3 ·
Can I use the 846 cam in my LT1? I saw the 350 Hot Cam kit in Jim Pace's catalog and I like it
(BTW, ever deal with him?)

What are the real differences between the Hot Cam, ZZ3, and 846 cams?

I am buying a 2500 stall, Neal TC from Dan Ferraro on his GP. So a cam is next.

My wife will kill me if she finds out about all of this


Mike
 
G
#4 ·
Hey BrewDawg,

Here are the 3 GM cams:

12370845 Hydraulic roller design I:214 E:224 I:488" E:509" 112

12370846 Hydraulic roller design I:222 E:230 I:509" E:528" 112

12370847 Hydraulic roller design I:234 E:242 I:539" E:558 112

You might also want to consider the Comp Cam 304 which I have right now. It's a 210/220 with 0.500/0.510 lift with 1.5s and 114 LSA. It's a VERY torquey cam and you'll love it if you like burnouts


With headers, SLP converters and the Comp 304 cam, I went from 14.84 to 14.04! Quite a nice drop, don't you think?

------------------
George

1995 Impala SS "Cherry Bomb"
Best ETs: Faster than my '65 Chevy pickup
Mods : 93% stock
My Super Impala SS Website
 
G
#5 ·
To keep it somewhat streetable, I'd stick to one of the following on a 350 CI LT1 :

* ZZ3 : easily pass emissions, but pretty mild.
* 845 : good torque cam, more radical than above
* CC304 : See George's comments

The HOT cam is really not ideally set up for an SS (too "peaky", loses low end torque). The 846 or CC305 will be downright annoying on the street (also too peaky).

Ed
 
G
#6 ·
Hey Brewdawg, If you want a more streetable set up, check out the crane 40-104227. Add some 1.6 bowtie rockers and the crane 10309 springs and you will be on the road without even pulling the heads!

------------------
Mike Reese
96 DGGM SS
Cape Coral, FL

21 mods and ? yet to go

[This message has been edited by ReeseSS (edited September 02, 2000).]
 
G
#7 ·
Agree strongly about the CC304. It's a torque monster. I'm running it in my '95 9C1 along with ported AL heads, 52 MM T body,
Edelbrock headers, 1.6RR, F Car MAF, SSRI,
3:73,Flowmaster cat back and Ed Wright PCM and have run a best of 13.68 @ 100.2 MPH at Firebird (1325'elevation)It dynoed 306 RWHP and 344 RWT. I had the cc305 in the car for a while but really do like the 304 better.
 
G
#8 ·
Ed, George, & Mr D,

Thanks. You guys are great and have given me a lot to consider. MAN I LOVE this forum!!

Right now, I have the G-hann headers, high flow cats, B&B TriFlo exhaust, BBK 52 MM TB, et al. Soon to have a 2500 stall Neal torque conv through Dan Ferraro's GP.

So now, all I have to decide is what cam and gear ratio. My car is a daily driver and I am tending toward the Comp Cam 304 (per George & Ed) and the Crane 40-104227 (per Mike).

As far as gears, it seems everyone runs the 3.73's. Did you guys upgrade the driveshaft? Isn't vibration a problem? Although a daily driver, I have been known to drive 100+ MPH for hours. I've been told don't bother with the 3.42's by most. But others have said they prefer the 3.42's over the 3.73's for long trips.

Ed, as you know, here in So Cal traffic can be bad but we can get on some good highways out to Phoenix or Las Vegas and get going fast.

I've been vacillating over 3.42's and 3.73's for 2 months now. I wish I could drive both and see which I liked better. I hate it when I un-do a mod and like to get it right the first time.

George I know you have the 3.73's per your website. What do you other guys have?

Mike
 
G
#9 ·
BrewDawg,

Just thought I would throw in an additional comment about the Comp 304. You saw Mr.Ds best NA time of 13.69 at 100.2, my best time with similar mods was very close, 13.72 @ 100.7. But the best part is that the Comp 304 really seems to love Nitrous!

As an example, my best N2O time with this cam was 11.93 @ 114.45 with a 1.78 60'. So if you're thinking about the juice later on, it's just another plus


As far as gears, if you go to 3.73s, which I strongly recommend, the odds are pretty good you'll need the DynoTech driveshaft if you like to run 100+. Once I switched to 3.73s, I found vibrations starting around 90, which the DynoTech completely removed.



------------------
George

1995 Impala SS "Cherry Bomb"
Best ETs: Faster than my '65 Chevy pickup
Mods : 93% stock
My Super Impala SS Website
 
G
#10 ·
Brewdawg, I know what you mean, I went back in forth for a long time with that one. I am trying to stay centered on being as streetable as possible and went with the 3;42's. I think it was an error and will end up later switching to the 3:73's. Noticed some difference but not a lot, over stock.

------------------
Mike Reese
96 DGGM SS
Cape Coral, FL

29 mods and ? yet to go

[This message has been edited by ReeseSS (edited September 03, 2000).]
 
G
#11 ·
Go with the 3.73's. IMHO, there's just not enough difference between the 3.08's and 3.42's. If you're looking for more performance, that is!

On the driveshaft question, my Goodwrench mechanic offered up a tip on this. I had absolutely no vibrations at any speed with the old gears or the new ones, by the way.

Here's what he says. Look at the pinion yoke; if it is externally balanced, ie., there is a weight on the outside of it, you probably won't have a vibration problem, if you go to lower gears. He says that means the driveshaft and pinion yoke were balanced as an assembly. If the pinion yoke has weight on the inside, it was balanced with the gearset, and will probably have to be replaced to eliminate vibration. That's what he told me, and he's been a good mechanic.YMMV


------------------

SSeeya,
Bob Dannelley
95 DCM-13.783@98.461
HOSS #144
 
G
#12 ·
Brewdawg, Others, Go with the 3:73s I did 3:42s first, thinking 3:73s were to much gear.WRONG!! Well I then switched to 3:73s. What a difference! They are probably my personal favorite of any mod I did. They will put a smile on your face real fast. I don't usually take the car over 100 (Because of the s rated BFG's that are on it) and ~110
has been it and I haven't had any vib problems.
 
G
#13 ·
Brewdawg,

One more vote here for the 3.73's. I did them about 6 months ago and haven't been sorry yet.. especially when smoking that Rustang from the lights.
I have slightly more vibration at about 85, however this smooths out by 95 and continues to be smooth to up over 145. My pinion yoke has weights on the outside and I also have weights welded to both the front and the back of my stock driveshaft.

Oh I have to warn you though, you might experience other problems, like worn out tires and excessive wheelspin


Another option if you have vibration problems is to have your stock driveshaft balanced. Although I haven't investigated further than asking a few of my motorhead friends, apparently there are a few shops even in my area (not a large metro complex by any stretch of the imagination) that perform this service.



Chris - '96 DCM
E-mail csm1@triton.net
Webpage http://web.triton.net/csm1/index.htm
 
G
#14 ·
Hey Brew, I would look into that Crane 227 a lot more if you havent already...That appears to be the best looking cam out there for stock heads...It has such a great exhaust side that it will really help you keep your torque...Combine that with some 3.73 gears and you will be set!!!

------------------

94 Impala SS -
13.095 @ 104.69 N/A
12.831 @ 112.24 N2O
 
G
#16 ·
Like I said, you guys are the BEST.

Well, it's decided. I'm going with the 3.73's.

Mike, thanks for co-miserating and your advice.

Bob, great tip on the pinion yoke. I'll check that out. Looks like my next mod is the gears.

All others, thanks.

Just curious. There was a GP on the HOSS page for a Dynotech MMC Aluminum Driveshaft for $340. Anyone have a good price on it now?

Mike
96 BBB

[This message has been edited by Brewdawg (edited September 04, 2000).]
 
G
#17 ·
Like AutocroSSer said, my 396 LT4 engine with the GMPP 846 cam passed smog, mostly due to Ed Wrights programming. (With 30# injectors).

The 846 cam (222/230) was fine because of the 396 cubes and almost 12:1 compression. For a 350 engine, I would go with what several guys have recommended:

GMPP ZZ3
Crane 227
CompCams 304

The 227 might be a problem though if you were swapping in the cam on the stock heads with 1.6 rockers, because the exhaust lift becomes .552, kind of high for the pressed in studs.

For gears, I had in the 3.42s and then switched to the 3.73s later. There is no comparison between them in terms of acceleration. The 3.42s are a noticeable change from stock, but the 3.73s feel like you swapped in a 383 motor. Only trouble is, on those long freeway cruises to LA at 80 mph, wish I had back in the 3.42s. Overall, I would go with 3.42s, if you plan on a lot of freeway driving. For mostly around town and racing, the 3.73s are the better choice by far.

FWIW, most guys like 3.73s better, even for the freeway, since the rpms are not really that bad and the passing power is tremendous.

Marc.
 
G
#19 ·
Actually I am running the 846 cam in my stock bottom ended 350...I love it!!! Dont know about smog but sure pulls hard...

I am pretty heavilty modded though...Wouldnt recommend it to everyone...


------------------

94 Impala SS -
13.095 @ 104.69 N/A
12.831 @ 112.24 N2O
 
G
#21 ·
I just wanna add a bit here although it looks like I came in a bit late. I just installed the Crane 227 cam and with stock converter and 3.73s, this beast will absolutely roast the tires!!! Unfortunately I'm currently waiting for my pcm to return from Thunder Racing where it is getting its idle adjusted because of a low and surging idle(in gear).

<BLOCKQUOTE>quote:</font><HR>The 227 might be a problem though if you were swapping in the cam on the stock heads with 1.6 rockers, because the exhaust lift becomes .552, kind of high for the pressed in studs.<HR></BLOCKQUOTE>

Doh!!
I pray I have no problems with my stock press in studs...

Oh yeah, go with the 3.73s! If I could do it all over, I woulda gone 4.10s. BTW, Hey Mike(Reese), thanks for telling me about this cool board!!


Scott




------------------
Black 95 Impala Super Sport
AR Torq Thrust lls
SLP coldair
DRM program
Dynomax UltraFlo
3.73s
Crane Cam 210/224
Bowtie 1.6 roller rockers
lead foot mod
14.59@95mph before cam and RRs
 
G
#22 ·
Scott, Glad to see you posting here! Can't help but not like it! Let me/us know the difference it made when you get the PCM back!

------------------
Mike Reese
96 DGGM SS
Cape Coral, FL :)
Lots of mods, but never enough!
 
G
#24 ·
Hey Mr. D, He forgot to mention on his post that he went with the crane 10309 springs, I got a set from CriSSis on this board and even though they are conservatively rated at .550, they will handle a little more then that.

------------------
Mike Reese
96 DGGM SS
Cape Coral, FL

Lots of mods, but never enough!

[This message has been edited by ReeseSS (edited September 17, 2000).]

[This message has been edited by ReeseSS (edited September 19, 2000).]
 
G
#25 ·
Yeah, I have the Crane springs too. I figured that would be obvious so I didn't bother to post it. Reese, I'm just getting the idle adjusted in the pcm, nothing else. I'm thinking about calling Ed Wright tomorrow to see if he'll send me a programmed pcm and I will just send him mine when I get it(core charge).

The current DRM program that I have will probably not be up to par with the new cam. For a stock motored LT1, DRM's program was a delight though. It would allow me to hold 1st gear up to about 12-13mph before shifting(at part throttle),raised the shift points, and shift firmness was great. Most guys that rode in my car thought it had a shift kit in it. How is Ed's programs as far as shifts, etc??

------------------
Black 95 Impala Super Sport
AR Torq Thrust lls
SLP coldair
DRM program
Dynomax UltraFlo
3.73s
Crane Cam 210/224
Bowtie 1.6 roller rockers
lead foot mod
14.59@95mph before cam and RRs
 
G
#26 ·
Scott, It won't cost any different to have him do 1 thing, or 20!
I would guess both programs are simular regarding shift firmness. Ed Wrights is much firmer then stock, but not the same as the trans go shift kit (with two washers). With the stock TC it is great, but it will get soft when you go with a higher stall TC. When you do send it in, you will probably want to bump up the shift points with the new cam. I am going to get them set at around 6000 rpm 1-2, and 5900 for rest.

------------------
Mike Reese
96 DGGM SS
Cape Coral, FL

Lots of mods, but never enough!

[This message has been edited by ReeseSS (edited September 17, 2000).]
 
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