bayer-z28

iTrader: (14)

Wanted to ask this in the 102/92 thread, but it woulda been a HUGE jack.

This is how I have been seeing the relation to the head flow, cam lift and intake flow. Typed it up on the local boards as a response but I want to check its accuracy. (Afraid of the critique, actually) Someone on the local boards was telling me that flow numbers don't mean anything. =

What I mean here is a higher flowing set of heads will allow more air into the engine earlier in the lift cycle Vs. a set of "stock" heads which would take more "time" to fill the cylinder. More air quicker, is probably the best way I can summarize what I am thinking here.

Also, as far as volumetric efficiency, I swear I read a formula somewhere here a long time ago on the amount of air a 346 or 364 can ingest with this going into volumetric efficiency. This Number in relation to the amount of air the intake and heads will allow.

bayer-z28

iTrader: (14)

BUMP...

Also, Tony, I would like some clairification on this:


If the TB was not an obstruction on the 102 as it was (slightly) on the 92, would this mean that the air speed has decreased? Same volume with a larger "hole" = slower?

I am starting to see that the 102 MAY just out-flow my worked over 243 heads. Someone mentioned it in the other thread and it kind of dawned on me. I don't think I'll flow more than ~280cfm at peak lift and the 102 (ported though) would flow past that.... If the airflow is slowed down, would that kill low end?

bayer-z28

iTrader: (14)

Mamo???

Anyone??

_GTO_

Interesting thread .

Subscribed...

bayer-z28

iTrader: (14)

^ You have subscribed to me talking to myself.


(for now, hopefully) Like Mamo was saying "I'm trying to bring the TECH back to tech." I love discussions like this, just seems like pulling teeth to get answers.

msydow

i'm in too....should be interesting....anyone???

Austinma62

Very interesting, sorry I can't be much of help. Hopefully someone with more know how can chime in!

bayer-z28

iTrader: (14)

We can keep BSing about something till Tony responds to my PM and drags his brain in here..

Tony Mamo @ AFR

iTrader: (13)

OK...this thread is pretty funny talking about nothing....LOL

Guys...

When we are discussing fuel injected applications.....the size of the plenum and the opening or the TB (size) will have zero effect on "low end" power.

This is old school thinking stemming from the very real and often practiced applications where too large a carb might have been bolted on a particular engine combination.

The problem stemming from the fact the large carb slowed the airspeed down enough in the venturi's of the main body to negatively effect the carb atomization and therefore hurt power, torque, fuel economy, and responsiveness until enough RPM was generated to allow the carb to become more effective again (guys older than 45 will be nodding their heads up and down right now while reading this!).

We aren't atomizing fuel here folks....thats handled by the injectors and the real meat and potatoes of manifold design (runner length, shape, and taper) hasn't changed much from the 90, 92 or 102.....its very similar but the 102 does have a superior shaped runner (although the length is very similar), is slightly taller, and ultimately flows more, especially when properly ported.

Yes....a FAST 102 can flow more than a 280 CFM head but thats always the case with a really good intake....ideally you want ALOT of headroom when selecting a manifold so when you bolt it in front of your heads it flows more net to the cylinder with the ultimate situation to not hurt the port any more than placing a radius plate in front of it. Thats pure theory unless we are discussing extremely optimized straight shot tunnel ram style manifolds.

I can port a Gen I single plane intake and make it flow 400 CFM.....when you place it in front of a 300 CFM intake port that port still loses 20 CFM which is very good all thing considered. Take the same intake unported by me that still flows way more out of the box than the 300 CFM intake port in question (say the intake flows 360 CFM out of the box) and now you may only see 265 CFM when placed in front of the head because it hurt the net flow more.

INTERNET MYTH #1 .....My 102 Fast is too big for my 346

Wrong....its a better designed intake thats going to allow more air to pass thru the intake ports and be mixed with more precisely atomized fuel from your injectors.

INTERNET MYTH #2....Its already big....you dont need to port it (or it might hurt the bottom end).

Also wrong....at least when ported properly. Once again it simply makes a good piece even better but I would be the first to admit that on a marginal set of head the gains from the work would be less as well. The better the heads, the more aggressive the RPM, displacement, etc. the more that ported 102 is going to pay you in spades.

The larger the restriction the intake manifold becomes....the better your results will be when you swap to the better intake.

If your still questioning anything lets get it handled now and please refer other people back to the answers when we see the same questions and bad information in other threads....I wish I had a nickel for the guys convinced their inaccurate theories are accurate....LOL

The ONLY potential negative to the 102 design...well besides the cost of admission with the rails etc.....is the TB (airblade) is so large it can create drivability challanges with the tune but its a much easier deal on a cable operated 102 with an IAC motor. ALso, it tends to be extremely responsive which I personally like, however some have complained its too responsive (on/off) and they have to get used to driving it. No big deal in my book....

Hope this helps!

-Tony

Greekey

iTrader: (3)

Nice post Tony. By the way, I've always wondered how many intake manifolds you port a month? Or A day? Or a week?

bayer-z28

iTrader: (14)

This was my "oooooooohhh" moment.. Should almost go without saying. Otherwise, it's a good bit of schooling.. Easy to understand, but still kind of odd how it loses a little bit when attaching the intake.

I've heard a couple of the drivability and tuning complaints, but I think with the right MAF or SD tuner, I shouldn't have a problem. Still thinking of going SD on this. I should have my 102 ordered by the end of the week..

Tony Mamo @ AFR

iTrader: (13)

LOL....good question

Some months more than others!

I know for a fact I have ported over 200 of them since 2004....not to mention have the carpal tunnel to prove it!

OP....if your thinking about having the manifold ported why don't you just buy it thru me....I will get you (and anyone else) a very competitive price.

The 102 is a much better piece from the standpoint of being a more robust rugged piece (its actually three pound heavier). Its just a better design....the move from the 90 to 92 was really nothing more than a slightly larger TB opening....the 102 is far more groundbreaking with the separate removable runners, etc. My only personal pet peeve with it was they forced everyone to spend even more money on fuel rails but what can you do....if you want to play you have to pay as they say.



Cheers,
Tony

White'89

iTrader: (3)

That was a rather interesting read and cleared up a few 'inaccurate theories' I had myself. But I have 1 question, will the same remain true in a forced induction application?

Tony Mamo @ AFR

iTrader: (13)

Yes....

Think of a blower the same as driving an N/A car at some retarded negative D/A

Its just a larger pressure drop from the plenum (pressurized) to the combustion chamber or business side of whats generating your cylinder pressure.

N/A engines see 14 PSI or so.....at 4 PSI of boost essentially thats an N/A engine experiencing 18 PSI....a situation that could almost occur at a track close to sea level on some frigid cold day (say negative 2500 D/A just to throw out a number).

Anyway....its all the same principles....a blower just represents a greater pressure drop which obviously better fills the cylinder.

-Tony

bayer-z28

iTrader: (14)

Tony; Someone mentioned the idea of air stalling in the runners during low RPM and part throttle operations... Can you address this concern?

Sorry to nit-pick this, but a grand for an intake/TB is a commitment. I'm in a debate on the local boards about this. And I'll admit that I am still slightly on the fence. Still getting everyone and their mother telling me that the runners are too big. I don't know how it can be. They seem to be the same size as the 92, just removable, which take up more room in the intake = bigger overall body.

bayer-z28

iTrader: (14)

BUMPs

Tony Mamo @ AFR

iTrader: (13)

Honestly that's a scary quote....(air "stalling" in the intake runners)

Even at idle you have eight pistons 4" across moving vertically close to the same depth at 6-7 times per second (just counting the "intake stroke" in the four cycle engine, not the power stroke)....trust me there is no air "stalling"....its moving thru that plenum at a pretty good clip (because there are eight cylinders pulling from the plenum) and moving thru the runners at a reasonably brisk pace as well. Start turning some RPM's and look out....you guys would be amazed and how much airflow is really moving thru only a 500 HP engine combination. A 300 CFM intake port @ 28" depression will suck you hand to that head (if you get close enough) with enough force to hurt you and that doesn't even represent whats really going on when an engine is at full song.

The good thing about the Internet is the plethora of information available to digest.....the bad thing about the Internet.....yes you guessed it....the plethora of information available to digest.

You need to be selective about who's theories and opinions you might latch on to....

I have seen so much bad info "parroted" from one source to the next its crazy.....

Always verify the accuracy of the source in question....whether discussing engines or which electric razor might work the best.

I love researching things on the Net but I have a pretty good nose for what info might be accurate and what info might not be....comes with age I think though

-Tony

bayer-z28

iTrader: (14)

^ Good deal, boss. It just seems that everyone on my local boards I talk to, all seem to back the local tuner and that throws me. Nut-swingers or do they know something I don't? (What I was thinking) Then I quote you on there and they STILL tell me not to listen. It's just frustrating dealing with the "internet experts" and all.

I sent PatG (I'm running his custom cam) a PM and asked him he he recommends. He will have the final say. Otherwise, I would go with the 102 based on the THOUSANDS of different ways I've dissected this and read all of the data.

Tony Mamo @ AFR

iTrader: (13)

YOU have to be smart enough to figure out who the real experts are than don't you....

Is it really that difficult....I dont think so.

You know I work really hard on my reputation and only dispense advice (freely I might add) that I know is deadly accurate with results proven to me on the flowbench, the dyno, and usually both. I head up the R&D and Product Development (spending most of my time designing cylinder heads and intake manifolds) for one of the most respected companies in this field, not to mention am a fairly proficient engine builder outside the four walls of AFR.

I'm just curious what the credentials are of the other people your inclined to listen to? Who's in a better position to make a more accurate call of what we are discussing here and has a pretty good reputation doing so?

And truthfully I'm a little disappointed about the fact in another thread you mention that some allude that I am just a "salesman" or "poster boy" for FAST. While I realize you didn't say it yourself I'm still "troubled" you even typed and included that in one of your posts seemingly questioning it....especially after the time I spent trying to clarify things for you so you could make a more informed decision.

Listen....I don't care if you take my advice or not....really I don't....but I would encourage you (or anyone unsure which path is best) to do your homework and maybe get more opinions on who's advice you might want to take. Whats a few more days going to change. Research....its pretty easy if you spend a little time to see who's on the ball and who isn't or might not be.

Anyway...I'm outta here....this is too much drama.....I've got some Kirby vacuums I need to unload!

-Tony

bayer-z28

iTrader: (14)

^ PM sent.. Was a misunderstanding. I was catching flack on another board. I TRY and dispel the myths and people are still telling me that it's BS or don't trust the data. Personally, I'd rather take the word of someone who's been doing years of R&D over someone who read a review on the internet that they decided to believe (With incomplete data I may add.) Which turned out to be an inconclusive test to begin with. Such as HPTV that throws a new intake on a "Shows a five hp gain!"... When it wasn't tuned and the fuel system was not addressed.

Such as the people that see the "runaway Toyota" sotries on the news and proceed to slam Toyota when it wasn't their fault to begin with.

Anyway.. I didn't mean to sound like I was the one who was bashing your reputation or R&D work.