dr_whigham

iTrader: (49)

I will promptly delete this thread if my base of thinking is WAY off.....

That being said, here we go:

For the last year or so I've read various, well, at least 20 threads that come along asking things like "biggest throttle body on ls6" & "any gains from a 90mm or 92mm TB on an LS6" and yada da da da.

Everyone seems to have the base of thought that since the intake itself is 78mm, the larger TB will make no difference. I beg to question that theory.

**Suit zipped, helmet on, faceshield down**

Here's MY train of thought. Lets say my heads are my lungs, my intake manifold my throat, and my throttle body my lips. With me so far?

My lungs and throat are a constant, meaning they stay the same size when breathing, no matter what. However, if I purse my lips together, or breathe through a straw, its harder to get air. Now, if I open my mouth wide (throttle body), its easier for air to get through my throat (78mm intake) to my lungs (heads). We do this when we run to get more air and our body certainly seems to like it.

I never question ANYONE on here. I simply search and find my answer. Without fail, too. This has been the topic of much discussion in my head though. (You know, when you're trying to fall asleep at night, thinking of ways to eek out every last bit of HP out of your car you can, then suddenly remember you're broke, the economy sucks, gas prices are through the roof, the sitting president is unpopular as hell; reminds you of the 70's all over again. Don't deny it, you all do it....)

BACK ON TOPIC

I found this while I was surfing tonight. That's the damned smoothest transition for this I've seen ever. It also solves the "turbulence" issue most bring up, that I agree with, and it completely kills the point of 3 bolt vs 4 bolt flange that is usually the last spear thrown to kill the conversation, thus effectively casting the OP to the pits of doomed question hell.

Thoughts, comments? Looking for some theory behind this, not just the sheep that have been led by sheperds.

I'd like to know HOW this wouldn't make it easier for your car to get air. If I can use a FTP 98mm lid, 85mm Z06 MAF (let's not debate THIS one), and a 90 or 92mm throttle body, with a SMOOTH transition, it just seems perfectly logical to me that I would indeed make more horsepower via velocity into the heads. Same reason we all go smaller head chamber. Velocity = speed, speed = power.

I may very well regret this come tomorrow......

Jimmy P

iTrader: (177)

You can try it and let us know what the results are, but I am skepticall you will have any noticeable gains..Well maybe a lighter pocket because you would need to buy that $75 adapter and then a 90 TB. I could be wrong though!

I think you would be better off saving for something like a FAST if you want to get more intake for your money. If you are interested I do have a FAST 78 with a 80 TB that matches to it perfectly for sale..Now that will def show you gains.

bayer-z28

iTrader: (14)

The only benefit you will see is from the smallest size of that adaptor plate. Being 75mm.

You can have a 100mmTB and if it necks back down to 75mm, you will see almost nothing except a change in throttle response. -MAYBE ..... That's it.

The problem is, you're not opening your "mouth." -Per your analogy... You're still breathing through a straw, you're just sticking a funnel at the other end of it. The mouth isn't the TB. That's only part of it. The mouth would be the opening of the intake itself. It would be the same thing as why TB spacers don't do anything. They've only shown around .6 hp gain. And that could have just been a differentiation in the pulls.

And then again, the TB size does not depict how well an intake will perform. The PP intake has a 96mm, but it's a dog on an NA car. Compared to a BBK (Lets say) with a different runners and an overall better intake, it will scream in comparison. Even with "only" an 85mm TB. Now add some porting to it to smooth everything out.

brian_rs/ss

hey OP you part of the reserves out of LA?

dr_whigham

iTrader: (49)

Negative. I tried to get back in around '07 for the reserves, and they told me "no" b/c I have a full sleeve tattoo..... .........

Yeah, I'm serious. Apparently when I got out in 05, I missed the "grandfather phase" that ended in 07, so none of it was in my SRB even though I've never gotten a new tattoo since I was active duty.

I just figured the hell with it. Maybe when we get a Commandant that wasn't from the ******* wing that **** will change and I can go back.

Anywho, please feel free to post in my "reversed flowmaster merge" thread also. Looking for ideas.

Thanks for the responses so far guys, keep em coming!

bayer-z28

iTrader: (14)

^ I tried getting back in too........ no go.... (MEB'd.. I developed asthma) Got pushed out in 08.

dr_whigham

iTrader: (49)

So from what I've seen so far, the concensus stands that there seems to be no change with air velocity? Doesn't make sense to me. Regardless of the opening in the intake, if air has a way to get in faster, doesn't that equal power? Not necessarily HP, but faster revs still equal speed, correct?

99Bluz28

iTrader: (35)

The Larger TB will help some, but the smaller intake inlet regardless will limit your power gains, IMO stick with a ported factory TB or a aftermarket 80mm TB. Another option is a BBK SSI w/85 tb or a TPIS LS6 90 w a 90-92mm TB..

The only way I see to benefit from using that adapter is to open up the intake inlet in the 10:00 through the 2:00 position and do the same with the adapter. That way you still have the outer perimeter of the intake seal intact to prevent any vacuum leaks.

dr_whigham

iTrader: (49)

Well I, like others, really want a 92/92 set up, and especially a 102/102. I just can't right now (See 70's talk in post #1)

I'm more or less looking for pro's and con's of using the tapered reducer for the time being. I mean, if I can find killer deals on let's say, a 92TB and an 85mm MAF, why not USE them for the time being, rather than have them be shelf decorations? It surely couldn't HURT, as long as the transition to the LS6 Mani was smooth and tapered, which that one happens to be.

I never bought into the idea of a BBK or PP. I want to do it once, do it right, and be done. Before anyone throws that exact line back in my face, I WILL be doing it right, I just want to USE the parts while I'm scraping funds together for a FAST manifold. All I'm out is 79 bucks for the transition plate, and I'll probably sell that with the LS6 manifold as a bargaining chip.

Hell, who knows? Maybe we never made extra power with just the 92 on the LS6 due to turbulence entering the smaller intake manifolds opening. What if this solved it, smoothed it out, and gained like, let's say 8rwhp? People spend 60 - 70 on a smooth bellow that's never really been PROVEN to work. WHAT IF..... this did?

I guess the point I'm trying to make is I see all the time people say NO GAINS, NO GAINS.... All I'm trying to debate here is that-

a) will it work?
b) MIGHT it make a little power?
c) just prove that you can piece your system together and use the parts while you wait and save for the final edition, being the manifold.

99Bluz28

iTrader: (35)

Well if it's just a stepping stone I couldn't see it hurting anything(very nice adapter transition) , and it will at least make some power gain(less restriction with larger TB), but I couldn't really say how much.

bayer-z28

iTrader: (14)

^ That's what I was thinking, but what I was leaning toward is the theory of a larger 'radius' at the front. Like how they use them when testing heads and intakes. It'll smooth the transition a little, but I'd also take a dremel to the spacer and 100% match it to the new TB and to the intake. Any step in one of the three pieces will cause turbulence.

It'll prolly ease the airflow, going to a 90, but then again, not a lot of people have tried it. Wondering how the mind will influence the butt-dyno on this one also. "mental mods"

dr_whigham

iTrader: (49)

True about "mental mods" and a good point as well. I think all too many times we strap on something like a smooth bellow and convince ourselves "I was pullin a lil harder up top..." when we simply know it's just wishful thinking.

I actually think I'm going to get one of these and give it a shot. The company that makes em checked out the thread here, but won't comment for fear of getting banned. I actually think they are allowed to talk ABOUT their product, just not point to where to BUY it.....

All in all they said theyve sold about 200, no returns, and no complaints. I whole-heartedly agree though, this is just a band-aid until you can get your manifold, but its a pretty damned cool idea, considering if the lips match both ends, and it allows you to use your TB for the time being. All in all, a cheap, well machined stepping stone piece.

Irish350

iTrader: (14)

wouldnt the z06 maf be the bottleneck at that point? (i know you said ignore that part, but the rest is all sound to me)

i went with a 104mm ftp > 100mm tsp maf > 95mm ptm tb (to ported ls3 intake)

bayer-z28

iTrader: (14)

Look at how long the Granatelli thread has been going. They chimed in to defend their product.

If you're curious and don't mind spending the money to experiment, then go ahead. I think what we're driving home here is just don't expect much out of it.

Dyno numbers would be nice.

dr_whigham

iTrader: (49)

Agreed with the MAF. That was going to be a temporary thing as the Z06 MAF tops at about 440hp. I guess I mean the 85mm would flow better than the stocker.

This was just a thought in my head I had and thought I'd bring it to the "high council" so to speak. I'd like to get a 102 eventually, but then again, if I come across a 92 at a good price when I actually HAVE cash, I'd jump on it. I just seem to think there's some gains to be had as long as you have a smooth transition. Pics below, to get a better understanding.





In pic two it would appear there's a little work to be done with a dremel, but damn if that isn't close. That is an LS6 intake with the FAST 92mm, BTW.

01ssreda4

iTrader: (96)

Instead of imagining things as a mouth or lips or whatever else silly you can come up with, read some on fluid physics. Air is controlled by physics. Doesn't mean they have to make sense to the average Joe. I say fluid flows only as much as its least restriction (as stated above)....there's a formula for it flow vs. pressure or whatever. No point in putting a huge TB on when it has to neck down just to get into the intake. Hence the reason they were cutting the necks off the LS6 and putting 90mm snouts on them (TPIS).

dr_whigham

iTrader: (49)

I understand that, except modern physics also says you cant compress liquids, hence hydraulic rams working the way they do.

On the other hand, you CAN compress air.... We're not dealing with a liquid that will only take the path of least resistance. We're talking about funneling more air inside a smaller opening.

The same way you get different barometer measurements during a thunderstorm or a tornado. If air has plenty of room to flow and smoothly gets necked down to a smaller ID, then you have a ram effect that will increase in velocity.

I also didn't think my references were silly. I was trying to use a base even the layman would understand.

01ssreda4

iTrader: (96)

Not really silly per se, more incorrect is what I was going for. I just didn't see the correlation as well as you did. But I'm a realistic thinker, there's no need for analogies between items that IMO are too different by design. Quite possibly no matter how you look at it, a flow bench may be the only way to 100% confirm a "best" design.

And maybe instead of physics.....fluid dynamics would have been a better suggestion. Maybe not, I'm not some geek with my head in a textbook 24/7.

dr_whigham

iTrader: (49)

Well, I'm certainly not trying to be an *** about anything and call anyone "silly" for having ideas and throwing out thought. I'm simply trying to gain perspective on this idea.

We've never had a way to bolt a 90 or 92 to an LS6 to give a comparison before. There was always the lip to contend with and turbulent airflow. I agree with you on the flowbench though. I think that between that, and back to back comparrison on a dyno, we may never know. SOTP simply doesn't work.

bayer-z28

iTrader: (14)

^ Well, some of it is, the air is not being forced into the transition, it is being sucked from the other side. -But you DO have atmospheric pressure on the TB side. So technically it IS indeed being forced from an area of higher pressure into an area of negative pressure. But it will still only flow as much as the restriction will allow.