Help me build my 350 and pass a sniffer test!
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Car: 1989 IROC-Z
Engine: L98 350
Transmission: New 700r4 Done by 11/14/07!
Help me build my 350 and pass a sniffer test!
I've just got done reading what felt like a million posts. Have you guys ever done a search on emissions legal anything??? Cheese and crow! I think my eyes are about to roll into the back of my head!
I've got an L98 in my '89 IROC, and it's time for a change. I was considering just having the stock block rebuilt and adding heads, intake, PROM and cam. If I were to simply choose the largest cam advertised as being "emissions legal" would I still be able to get a decent 350hp? I don't need to pass any sort of visual inspection, only the tail pipe portion.
I had planned on getting AS&M runners, a big mouth manifold, ported plenum, Trick Flow 23* heads, and hooker 2055's.
Would it be easier to just work off a ZZ4 short block and build from there? I've replace heads and everything external, but never a rotating assembly or cam. I guess I'm pretty apprehensive about doing it now.
Can anyone give me some good recommendations?
I've got an L98 in my '89 IROC, and it's time for a change. I was considering just having the stock block rebuilt and adding heads, intake, PROM and cam. If I were to simply choose the largest cam advertised as being "emissions legal" would I still be able to get a decent 350hp? I don't need to pass any sort of visual inspection, only the tail pipe portion.
I had planned on getting AS&M runners, a big mouth manifold, ported plenum, Trick Flow 23* heads, and hooker 2055's.
Would it be easier to just work off a ZZ4 short block and build from there? I've replace heads and everything external, but never a rotating assembly or cam. I guess I'm pretty apprehensive about doing it now.
Can anyone give me some good recommendations?
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Car: '89 Trans AM/'88 GTA
Engine: (2) Tuned Port L98's
Re: Help me build my 350 and pass a sniffer test!
Well, It easy to pass a newly rebuilt motor through
the sniffer.. Its the old high mileage ones that have
the trouble.
With the mods you mentioned, you should'nt have
a problem as long as its tuned properly and your
running at least a single cat.
Id watch out for what cam you stick in there,
and chances are you wont get a Tuned port motor
to make past 350HP street legal easily..
the sniffer.. Its the old high mileage ones that have
the trouble.
With the mods you mentioned, you should'nt have
a problem as long as its tuned properly and your
running at least a single cat.
Id watch out for what cam you stick in there,
and chances are you wont get a Tuned port motor
to make past 350HP street legal easily..
#3
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Car: 1989 IROC-Z
Engine: L98 350
Transmission: New 700r4 Done by 11/14/07!
Re: Help me build my 350 and pass a sniffer test!
Thanks for the response. I know this sort of topic has a habit of scaring off the people who really have a good head on their shoulders when it comes to engine builders, but I guess I was hoping to get lucky. Maybe I should do some checking with the local speed shops and see what they recommend. I suppose I could always put a Vortech supercharger on after the other mods and that would help me breach 350hp.
TPI, being from Arizona maybe you would have heard of a Camaro they build one of the Super Chevy mags. It was an '82 Camaro they put a 400 block in and made it a 377. It had a Super Ram intake and a Vortech T-trim that put out like 26 pounds of boost. It was built in Arizona, so I'm guessing it must have had to pass emissions tests there. Do you know anything about it?
TPI, being from Arizona maybe you would have heard of a Camaro they build one of the Super Chevy mags. It was an '82 Camaro they put a 400 block in and made it a 377. It had a Super Ram intake and a Vortech T-trim that put out like 26 pounds of boost. It was built in Arizona, so I'm guessing it must have had to pass emissions tests there. Do you know anything about it?
#4
Re: Help me build my 350 and pass a sniffer test!
There have been several threads lately about 350 buildups, so I can imagine the information overload.
What I would do is take a ride over to the SoCal forum and read up on some of the builds my father Dyno Don has done, and that I have tuned. We all pass CA smog cleaner than stock and put down anywhere from 300 to 350 RWHP thru sticks and automatics.
Here's my recipe:
350 block
Trick Flow heads
XFI268HR camshaft
SLP 1 3/4" headers (or Dyno Don headers if we ever get them back from the bender)
Edelbrock TPI intake
SLP or AS&M siamesed runners or Accel SuperRam
52mm throttle body
custom mandrel-bent 2 1/2" dual-cat y-pipe or single-cat 3"
3" or 3.5" mandrel-bent exhaust
Magnaflow muffler
This assumes all pieces are ported, gasket-matched, and you're running a custom chip optimized for the engine.
What I would do is take a ride over to the SoCal forum and read up on some of the builds my father Dyno Don has done, and that I have tuned. We all pass CA smog cleaner than stock and put down anywhere from 300 to 350 RWHP thru sticks and automatics.
Here's my recipe:
350 block
Trick Flow heads
XFI268HR camshaft
SLP 1 3/4" headers (or Dyno Don headers if we ever get them back from the bender)
Edelbrock TPI intake
SLP or AS&M siamesed runners or Accel SuperRam
52mm throttle body
custom mandrel-bent 2 1/2" dual-cat y-pipe or single-cat 3"
3" or 3.5" mandrel-bent exhaust
Magnaflow muffler
This assumes all pieces are ported, gasket-matched, and you're running a custom chip optimized for the engine.
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Car: 1989 IROC-Z
Engine: L98 350
Transmission: New 700r4 Done by 11/14/07!
Re: Help me build my 350 and pass a sniffer test!
That's awesome and an absolutely FANTASTIC suggestion! I truly appreciate your help.
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Car: 1988 Trans Am
Engine: 305 TPI - LB9
Transmission: 700R
Re: Help me build my 350 and pass a sniffer test!
Ohio discontinued the Emissions checking they used to do, after they got sued because air quality didn't change at all in the 15 years they were doing it...
I still think by and large, it's just a scam, but good luck with it.
Couple things I know about it - make sure those plugs and wires are in good shape, tune with low octane, but run high octane on the test and another big thing is to make sure those Cat's are heated up when you test, that can make all the difference in the world - a good 30 minute drive should do it just fine.
Oh and cooler days are better to test on, if you can manage that.
I still think by and large, it's just a scam, but good luck with it.
Couple things I know about it - make sure those plugs and wires are in good shape, tune with low octane, but run high octane on the test and another big thing is to make sure those Cat's are heated up when you test, that can make all the difference in the world - a good 30 minute drive should do it just fine.
Oh and cooler days are better to test on, if you can manage that.
#7
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Car: 1989 IROC-Z
Engine: L98 350
Transmission: New 700r4 Done by 11/14/07!
Re: Help me build my 350 and pass a sniffer test!
Got it. A cool day in Las Vegas? Hmmm.... Maybe in about 6 or 7 months!
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Car: 83 POS monte carlo 2015 chevy P/U
Engine: 92 5.7 tpi 5.3
Transmission: 700r4 6L60E
Axle/Gears: 2.42 too high
Re: Help me build my 350 and pass a sniffer test!
if you want to stay with a LTR TPI setup, i would look into FIRST injections.
for about $1000.00 you get a base, runners, plenum, & a throttle body.
they may have the base for Vortec heads ready to sell.
http://www.firstfuelinjection.com
BBK "may" be getting ready to bring their TPI intake to market. its been talked about for quite sometime, so don't hold your breath.
for about $1000.00 you get a base, runners, plenum, & a throttle body.
they may have the base for Vortec heads ready to sell.
http://www.firstfuelinjection.com
BBK "may" be getting ready to bring their TPI intake to market. its been talked about for quite sometime, so don't hold your breath.
Last edited by DENN_SHAH; 06-07-2007 at 10:13 PM.
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