TheMysticWizard

iTrader: (1)

Okay I want to build me a mild 383 for my '87 305 TPI but I want to know if I will still be able to pass smog.

My Plans:

350 4 bolt roller block .040 over
Summit 383 Cast Crank (SES-3-51-05-002)
10.9:1 Keith Black Hypereutectic Pistons (UEM-KB100040-8)
Stock Chevy 305/350 5.7" Rods
L98 Heads, Heavily Ported (Alum if I find them for the right price)
LPE 74216 Cam (Or Close to it) (213*/219*, .462/.471, 112* LSA)
TPI Setup (Stock ported plenum, and base, Aftermarket Runners)
24 lb/hr Injectors (not sure on brand or size yet)
Edelbrock TES 6872 Chrome Headers 50 State Legal (EDL-68721)
3" Catco High Flow Cat (CTO-9118)

Does this sound like something that would pass smog if it was well tuned? I Know I'm not using all the best parts, but I am trying to keep it as cheap as possible, and hopefully legal.

Anyone have something simular to this in California and have no problem with smog?

TheMysticWizard

iTrader: (1)

bump...

So what do you guys think?

BLACK ICE

may be 383+TPI+major detuning= Cali emmisions
I feel really bad for you Cali guys.

Morley

If you can spare the $$ get the LPE/Accel base. It will flow the needed air to match your CID and the porting on the heads and plenum with aftermarket runners. Otherwise the manifold will be choking your engine bigtime, the LPE is 50 state legal and has all the provisions for emissions.

TheMysticWizard

iTrader: (1)

So how about one chip for performance, one chip for smog time? Think things would be cool then? I mean would a 383 Pass smog if it was running well, I mean would it put out much more pollution than a 350?

With time I hope to add more on to this engine, I would really like better rods, before a better base, but I'll get it all eventually. Funds are low for me, I aquire things as I can. It's tough being 17 (well 18 tomorrow, Monday) and wanting so much.

I Just hope if I put something together I will be able to pass smog testing.

Morley

That's why I was suggesting the manifold. I'm not sure (never really studied the effects of the manifold on emissions) but the stock base may make it harder to get the tune right for emissions, someone with more exp with emissions may want to yea or nay this idea.

TheMysticWizard

iTrader: (1)

Well If it's gonna be the difference between passing and not passing (being able to tune and not being able to tune) then I guess I will be saving up for a new manifold.

So is anyone from Cali running a 383, and passing smog?

89gta383

iTrader: (5)

I don't know how much more strict your law is than TN, but I passed with 383, 219 cam, superram and a 3" cat. I passed with my set up now of 230-236 .575-.578 cam miniram. All I do is swap in a flanged 3" cat for the test, but it is tailpipe only, no visual.

TheMysticWizard

iTrader: (1)

A friend (vjo90rs8) told me that I should try registuring my car with DMV with a 350 instead of a 305, since they would test it according to engine size and limits for each engine. I think it's a pretty good idea myself, but I don't know how pratical it is, and how to go about it... Any ideas? I figure I can tell them I want to legally put a 350 in my '87 Firebird, and it should be legal since '87 TPI Firebirds also came with 350's... sounds good to me.

I don't know how strict TN is on smog, but I am willing to bed CA will be stricter, and yes we have visuals here, but I am not anticipating a problem there... I plan on keeping my stock TPI, and adding a LPE/Accel base if needed.

I guess I will just have to try my luck with DMV and Engine Swaps... and see how it goes, If I am registured with a 350, and step up to a 383, I don't think it would be that much of a challenge anymore.

formula350sd

iTrader: (2)

well this might be a little apples to oranges but my car passed illinois emissions with rediculously burnt out cats fine and my brothers lt1 car the same so id assume that hopefully with cats (2 might be better but i dont know) and your air system working you may be ok as long as you have carb numbers for your aftermarket stuff and everythig else looks stock

TheMysticWizard

iTrader: (1)

I'm still debating it.. thinking I should just build a 350... I don't want to be screwed as far as smog.. it will majorly blow. If I can figure out how to let DMV allow me to put a "legal 350" in my car, I might go for the 383, otherwise I think I'll just go 350.

theno1prince

iTrader: (1)

Check out Jags That Run . They specialize in v8 conversions and know all about California smog regulations.

As far as your combo, I think you should be fine considering how mild it is. The only problem I do see is that the compression you're looking at is way too high. With aluminum heads you shouldn't run any more than 10:1. With iron heads, I'd say no more than 9.5:1. Both these would need 91 octane to avoid detonation.

f355bird

iTrader: (2)

i know with dodge small blocks the stroker motors alot of times put out less emissions then the a standard motor less stress and they aso run alot better all around.

Z69

You'll need Al. heads with that much compression and small cam.
You might want to go with the 12cc dish pistons instead of the flat tops. The compression may get you into trouble on the loaded test for nox. Since it's a 383, you'll need major chip tuning to get it to pass. Don't bother with the re register bs.
The limits are the same for a 305 or a 350.
Don't know where they got that idea.
You might want to go to FMS 24 lbs injectors. They are rated at a lower pressure so they flow more at the gm 43psi. This will make the tuning easier.
You could also try the DIY prom board.
You will want to do all of this just after your biannual test. That way you have plenty of time to get it right.
You won't believe the torque difference of a 383. Also do all the TPI mods you can. A 383 will need them.

Captain C

Here are a few suggestions from a fellow Left Coast resident.

1. Dump the L98's right off the bat. They don't flow enough for your 383 out of the box and will barely be enough fully ported. Also, they don't have the exhaust gas crossover. This will require that you modify any headers you get to work with the Corvette style hookup, thereby negating their CARB EO#. Buy a set of AFR's. With the mild cam you could get away with 195's and make a whole lot more power with room to grow in the future. Considering the price of the L98’s and the $1000 port job, it will be cheaper in the long run.

2. Lower the compression to no more than 10:1. The higher the compression, the higher the CO (or NOX, I forget which). Also, keep in mind that compression isn’t the only thing that causes pinging. Chamber design and cylinder pressure are the others. TPI tends to have a slight Ram Air effect that increases your cylinder filling efficiency.

3. Cam: The cam duration is fine and the lift ok for a 350 flat tappet hydraulic. I am passing smog fine with a Chevrolet ZZ4 Cam in my 350. You should be ok with a Chevrolet Hot Cam and 1.6 roller rockers in your 383.

4. Injectors: 24# are too small for your engine. I have them on my 350 and wish I had 28-30# injectors. The 24# injectors will feed my engine, but the duty cycle is like 85%. Way too high for good performance and reliability. I would suggest 28# if you are going to stay with a mild cam like the ZZ4 or 30# if you are going with the Hot Cam.

5. Throttle body: Use a 58MM with the 383. A 52MM works great with my 350.

6. Exhaust: Use 1 ¾” primary tubes in your headers if possible. You will need a lot of breathing with that 383. Also, use a 3” mandrel bent exhaust from the Cat back with a high-flow muffler.

7. Intake: Unless you are planning on doing the porting of the intake yourself, buy one of the suggested intakes above. It will run you about the same cash. Also, the runners will realistically limit you to 4500 rpm power range. I would suggest a larger diameter set. With my engine I noticed a major power increase in the last 5-700 rpm of my top end.

8. Use an adjustable pointer for your harmonic balancer. You can only have 6* timing show up. I have mine set a few degrees off so they think I have 6*.......

9. Don’t scrimp on the balancer!!!!!!!!! It will throw the timing off and cause you to fail smog. It will also cause your bearings to go out sooner. I currently have a 6 ¼” Fluidamper on my Camaro. It works excellent with 305’s and 350’s with lightweight pistons. It doesn’t work very well with heavy pistons. I just bought a 7 ¼” unit to replace it. I get to install that this weekend.

Bottom line: What do you want the engine to do?? If all you want is a little more torque, go with a stock L98 style 350, just use different heads. That way you can use everything off your car but the injectors. You could even use them if you install an adjustable fuel pressure regulator. BTW, you can also drop a 400 crank in your 305. They have to machine down the counter weights to get it to balance but you end up with 323 Cubes, IIRC


:werd:

TheMysticWizard

iTrader: (1)

Captain C.. Thanks for all the info! I will be saving that reply for sure!

I know the compression is too high... so that will be changed.
Different heads, throttle body, runners, injectors will be deeply considered. I will add an AFPR, along with a good balancer.

This project will be taking place in the future, probably more than a year from now. I have several things to take care of as far as suspension, rear end, tranny, torque converter and exhaust.

Really I am just collecting opinions as far as being able to pass smog.

I appreciate everyone's feed back, and it will all be taken into consideration as my plans begin to come together.