I have been bouncing between intakes for my new engine for some time now. I have researched them all and each seem to have their advantages and disadvantages. I cant tell how much of it is speculation, hyperbole, or down right proven facts.

Before anyone side tracks about "It depends on what you want to do", I will answer that now: a street performer that I can take to work and auto-x/race on the occassion (I dont drag race). It doesnt have to do 0-60 in less than 3 seconds, I can sleep at night knowing it doesn't have 500+ rwhp, and I dont expect to set any road course records. I do want to increase my performance and win a couple of auto-x's though!

I just got a set of 195cc AFR comp package heads (not installed yet) and have a modified exhaust (headers, High flow cats, and Borla Y pipe and mufflers). My current intake is the an Edelbrock with stock plenum (I dont think it was ported/modified) with the stock TB. I want to keep this within the realm of California emissions, which is why the 383 has been put on the back burner (I so hate the number 49!). Oh yeah, it has a black tag ZF6 with a centerforce clutch.

The main reason I ask this is because I have read that people get completely different results from the exact same setup with the only difference being the intake. Superram seems to be a favorite here though I have seen some who want/have switched to TPIS Miniram. No one seems to like the Edelbrock or cares to admit it except me !

Calculations are not necessary but if someone has used a combination of these intakes and seen a difference, I would really like to hear the story.

 

If you are running the BM base (though Edelbrock) & LT runners with a stock cam that is a great setup. Even with the new heads you should still have a package that works well together. You might consider having the intake extude honed to better match the new heads.

If you want to do something like a SR or MR intake get a cam to match the power band that the shorter intake runner length will generate.

 

Superram has CARB numbers, MR does not. And the the 74219 cam that is recommended for it can be tuned to pass.

 

From what you just described the Super Ram would be the logical choice for your combo/driving style.

 

As of right now, yes, I am running both the High flow base and runners from Edelbrock with stock cam. I actually called extrude hone about my intake (I was going to do the whole thing even though the plenum would be the one that would benefit the most) with a larger TB.

The Lingenfelter 74219 cam, right? That is a nice cam, where does it produce power? Not an expert on cam profiles. BTW, I thought the Miniram was a "replacement part" under California smog law? Could be wrong.

Like I said, the SR seems to be a favorite. Anyone run an Edelbrock and SR?

 

One note, you said you wanted to win some auto-x runs right?
By making the modifications you speak of you will be bumping yourself out of A Stock, which I presume you are in, and most likely into SM2. The competition in SM2 is really stiff and thats where all the big $$$ cars are. So I think you will have a blast with a SR/219 combo, but I wouldn't count on it being the key to winning auto-x's.

Also, I have talk to a forum member about his 383 (I know you are going 350 but the point is, he can feed this size motor) he is having sucess with a TPI hi-flow intake. He claims the torque really helps him out especially in auto-x.

That said I will be going with a SR'd 383 in SM2 for kicks next season.

Good luck!

 

I auto-x with a Corvette club here in California, I didnt plan on doing regional/national competitions. I do this for fun, not money. I does seem that the SR is a popular choice, I guess for good reason.

As for the 383, the only (and I mean only) reason I dont intend to stroke it out is due to California emissions. I have read articles about people who have built 383's and pass California emissions, but they have always used carbs. By experience with engines is quite limited and I am not prepared to blow several thousand dollars on an experiment that might fail. If someone out there has proven results, I am all ears .

 

Lingenfelter makes 383s that pass the emissions there, with '113 heads, SR and 219 cam. So with proper tuning it will pass by itself. Its easier to get an FI motor to pass sniffer than with just a carb and make better power, only thing about carbed cars is that the owner probably just changed some jetting to make it pass the test and went back to another race tune afterwards, doing that with your chip is possible as well but more expensive.

219 is a low-midrange cam.

 

California emissions have absolutely nothing to do with displacement, so you can run as many inches as you want. Passing the sniffer is simply a matter of how you cam it. Your intakes are limited to the SR or some kind of CARB approved TPI setup period. (I'm assuming your foundation is an L98).

To my way of thinking, an EO compliant L98 high po motor is a no brainer:

1. The largest displacement possible,
2. EO stickers for your heads and intake (the SR and AFRs are top drawer here),
3. A well matched cam that doesn't have an extended duration.

There may be people suggesting better choices out there for heads and intakes, but just ask for the EO number.........it won't happen

Check my sig for an emisions compliant 500ish buildup NA. Oh, BTW, NOS (nitrous) has an EO number too

 

Caboboy, you make a good point about tuning and smog. Its all about what can be seen and what the sniffer says. Your setup is very similar to what I originally planned (minus the 700R4 ). Do you have your most recent smog results? If a 421 can pass, 383 should be do'able. What kind of exhaust do you use?

As far as NOS, no thanks. Auto-x'ing and NOS dont mix well.

 

The biggest problem with smog is the valve event overlap, so a larger displacement engine would be even better as it can stand the overlap better.

As mentioned, with your cam you should be fine with a 383 and good tuning. The trick is to keep the ECM in full control of the A/F when in closed loop mode.

 

Would a wide band O2 sensor help as far as control and emissions goes? When I was checking out manifolds, one guy was going to sell me a full setup for the SR (intake, harness, injectors, Gen VII, TB, IAC, and wide band O2 sensor). He said that this would produce serious results since this setup would be easily tunable. Dont recall the exact amount but the setup was $$$. Too bad the Gen VII is illegal in California, probably could run better than the factory ECU could.

BTW, thanks all for you input. It is not falling on deaf ears.

 

Uhm... ok. So when you say valve event overlap, are you talking about LSA or is this different?

As far as closed loop mode, I am not familiar with that at all. I know what a closed loop is but I am not sure how it applies to fuel injection and engine management. Could you explain the last part?

 

Be careful that your actually seeming to make this more complicated than it really is. Superram/219/AFR195 combo w/stock ECM/custom chip has been done successfully more times than one can count. You should make about 440 chp, have near stock driveability, and easily pass Ca smog.

 

This is it in a nutshell!

 

Then I suppose that settles it. Thank you all for you input, it is much appreciated. With that sort of track record, there seems to be a SR in my L98's future.