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wrong generation
05-22-2009, 11:47 PM
what would be the ideal timing for a chevy 350 to pass smog ?

also does any one know the emissions standards for a 87 thirdgen with a 350 ? i know what they are for a v6 so wondering about what they are for a 350 so that i can see what my chances of getting the car to pass emissions is.

BonzoHansen
05-23-2009, 07:49 AM
They do not differ v8 vs v6

wrong generation
05-23-2009, 08:54 AM
i have two papers from the state inspection agency's one for a 305 v8 the other for a 173 v6 and both have totaly differant standards. so there has to be another out there for the 350 v8 or maybe its the same as the 305 ?? but theres deff a diff between the v6 and v8 acording to these two papers.

2.8/173 v6 standards
NOx 1227
HC 162
CO% 0.91

5.0/305 V8 standards
NOx 1110
HC 148
CO% 0.83

BonzoHansen
05-23-2009, 11:24 AM
A lot of googling..

If I read this right
http://www.nj.gov/dep/aqm/eimp297a.htm

LVW HC CO NOX
3375 162 0.91 1227
3750 148 0.83 1110

The difference is vehicle weight, not necessarily engine type. So it appears the 2 cars have different listed LVW thus different standards. It seems this came in as part of the roller tests. It did not used to be like that.


There is no ideal timing, every engine setup is different. You have a cat in the car?

NJ346
05-23-2009, 11:46 AM
zeek isn't the vin on your car for a v6? pretty sure you'll have to pass emissions for the v6. Plus, I highly doubt your car has a flying chance in hell of passing, just buy a sticker for $100 and be done.

wrong generation
05-23-2009, 12:22 PM
A lot of googling..

If I read this right
http://www.nj.gov/dep/aqm/eimp297a.htm

LVW HC CO NOX
3375 162 0.91 1227
3750 148 0.83 1110

The difference is vehicle weight, not necessarily engine type. So it appears the 2 cars have different listed LVW thus different standards. It seems this came in as part of the roller tests. It did not used to be like that.


There is no ideal timing, every engine setup is different. You have a cat in the car?



hmm both of the emissions/inspections papers i have in front of me were for the same car/same weight. both of them were for an 87 camaro sport coupe one a 305 the other a 2.8 i know the 350 came from an irocz which is a slightly heavier car but the other two car wise are roughtly the same in weight and everything except for a couple pounds due to the engines

yes the car has the a cat converter.

zeek isn't the vin on your car for a v6? pretty sure you'll have to pass emissions for the v6. Plus, I highly doubt your car has a flying chance in hell of passing, just buy a sticker for $100 and be done.

yes the vin on my car states its a v6 car. so ill have to pass emissions as a v6 which is why im trying to find out what the standards are for the thirdgens that came with a 350. to see what the differance is between them.

why doesnt my car have a flying chance in hell ? i have done everything acording to the federal guidelines for doing such an engine swap so techically and legaly it should pass emissions with out a problem its just a matter of getting the engine's tune to be smog friendly to give it the best chances possibly and then off to the states inspection place i go. every one like you keeps telling me that the car will never pass legaly and to just go and buy a sticker but how do you know that it wont unless you atleast try and attempt to do it ?
being that the 2.8 standards are higher then the 305 standards that actualy gives the car a fairly decent chance at passing. i kinda figured that sense the standards for the v6 were higher then the 305 that maybe the standards for the 305 would be higher then the standards for the 350 which if true would mean that there is a decent amount of leeway in there and extra room to use in order for the car to legaly pass emissions.

NJ346
05-23-2009, 12:38 PM
why doesnt my car have a flying chance in hell ? i have done everything acording to the federal guidelines for doing such an engine swap so techically and legaly it should pass emissions with out a problem its just a matter of getting the engine's tune to be smog friendly to give it the best chances possibly and then off to the states inspection place i go. every one like you keeps telling me that the car will never pass legaly and to just go and buy a sticker but how do you know that it wont unless you atleast try and attempt to do it ?
being that the 2.8 standards are higher then the 305 standards that actualy gives the car a fairly decent chance at passing. i kinda figured that sense the standards for the v6 were higher then the 305 that maybe the standards for the 305 would be higher then the standards for the 350 which if true would mean that there is a decent amount of leeway in there and extra room to use in order for the car to legaly pass emissions.

Last time I talked to you to made the 350 sound as if it was to be as fast, if not faster than my ls1, so I assumed you were going to run a fairly large cam=not emissions friendly. If you take the car to a state inspection and it doesn't pass for emissions, it's going to be harder to buy a sticker since the car is flagged and a shop would be taking an even bigger chance on passing you. But hey, I'm just giving you my opinion if I was in the situation you were in. Btw, wasn't this car supposed to be ready for the track meet we had all the way back in December...:loser:

wrong generation
05-23-2009, 12:46 PM
Last time I talked to you to made the 350 sound as if it was to be as fast, if not faster than my ls1, so I assumed you were going to run a fairly large cam=not emissions friendly. If you take the car to a state inspection and it doesn't pass for emissions, it's going to be harder to buy a sticker since the car is flagged and a shop would be taking an even bigger chance on passing you. But hey, I'm just giving you my opinion if I was in the situation you were in. Btw, wasn't this car supposed to be ready for the track meet we had all the way back in December...:loser:

hey between working and winters weather it took alittle extra time to get the car up and running but its up and running now lol. right now the cam is stock. but once the car has a valid inspection sticker then that will change :) but for now the car is to stay as emissions friendly as possible. hell i even have the charcoal canister hooked up to the engine lol

BonzoHansen
05-23-2009, 02:29 PM
How about offering engine details and then maybe you can get some advice. Cam specs, heads, intake, exhaust, etc.

JL8Jeff
05-23-2009, 09:42 PM
Did you talk to dmv about the engine swap? I think you may need some form of proof that the V8 is a newer engine than the original car/V6 engine was. As for tuning it to pass, your best bet is probably to go to a garage that has the tailpipe emission's test equipment and hook up and adjust the timing/idle, etc. There isn't a best timing setting, you have to play around with it. I had a pretty well built 396 in an old 68 conv a few years ago and it took us an hour of tweaking to get it to pass the tailpipe idle test.

Tru2Chevy
05-24-2009, 10:07 PM
How about offering engine details and then maybe you can get some advice. Cam specs, heads, intake, exhaust, etc.

I'm pretty sure the engine is a stock L98 longblock with your old performer intake and a non-cc 4bbl carb.

- Justin

BonzoHansen
05-24-2009, 11:09 PM
EGR?

wrong generation
05-25-2009, 07:39 PM
I'm pretty sure the engine is a stock L98 longblock with your old performer intake and a non-cc 4bbl carb.

- Justin

yup thats exactly it stock 87 L98 long block with a old performer 2101 and non cc 4bbl carb :)

EGR?

no egr thats the one thing the engine is missing. but it does have a cat converter and the charcoal canister hooked up. 2 out of 3 isnt bad :)

BonzoHansen
05-25-2009, 07:47 PM
You have a vac. advance distributor?

Does that manifold have an EGR provision? NOX might be hard w/o it.

Tru2Chevy
05-25-2009, 08:39 PM
2101 = No EGR.

- Justin

wrong generation
05-25-2009, 08:43 PM
You have a vac. advance distributor?

Does that manifold have an EGR provision? NOX might be hard w/o it.

yes vac advance. its a distributor from a zz4 crate motor with an accell super coil