Throttle body and Elbow Question
 

In terms of flow numbers here.

Accufab 4 barrel throttle body and a carb hat elbow

Vs.

Edelbrock low profile elbow and 90mm throttle body.

Forced induction build here.

Figure out max cfm of each piece and pick the combo with the higher min number. I would think a hat would be less effective.

Carb hat = huge, as in cowl modifying is needed to fit. :rofl:

I am just on the thought process that for a FI build, this sort of detail is not as needed.

In that case go with a hat ;)

Ok next question is how to determine whether you need the flow numbers provided by it.

Take total min flow number on intake tract,divide by 8 and compare to head intake flow number?

Elbow should be fine. . .

Even though countless people say they pick up power and ease of tuning by ditching the edelbrock low profile elbow?

Granted that is NA stuff, so I am not sure if the same logic applies for pressurized intakes.

x2. . .

90mm w/ elbow. No need for any other nonsense. You are not looking to make 2000hp & counting every 1/2hp.
There are guys making 1000hp+ on a stock ls6 intake which I believe is 78mm. Dont waste your money. Use it elsewhere.

p.s. remember... this is FORCED Induction.. The turbo will be forcing air into the engine vrs. N/A which needs the largest area possible to SUCK the air into the engine.

Yes, but I am also concerned with ease of tuning and since a turbo isn't constant like a blower, any restriction can make hell for the tuner.

Any thoughts on that aspect of it?

And then any thoughts on this?

lets start here....
what engine... lt or ls?
What intake manifold are you using?
Maf or S.D.?
up & foward or down & foward headers/manifolds?
turbo location? front mid mount or front high mount? center behind rad?

These details will most likely derail thread with nonsense and haters.

383 LT1, vic E single plane, SD, front headers, center behind rad.

The Lt1 is going to be your airflow restriction.... lol....sorry, just had to.

Seriously, use this to put things into perspective.
o.k. turbocharged engine has many different values to figure, but without going nuts and losing you on airflow, cfm,psi, pressure ratio, velocity, etc.. etc..etc..

A 3.5" intake tube will flow 1000cfm+ N/A, in which under pressure (turbo=psi)
multiplies the amount of cfm the same 3.5" pipe N/A will provide.

So lets say 1200cfm is the airflow that is going to be coming into your engine via the turbo.
150cfm= 100hp
so 1200cfm = 800hp
Which I believe is what your looking for.

Your 76mm probly flows in the neighborhood of 98-100 lbs/min which is approx: 1500cfm. which will put it exactly where you wanna be having quick spool, and 700-800hp with about the same or close in TQ.

Remember that the size pipe/inlet plays apart in velocity & psi also, the larger the pipe/inlet, the more psi it takes to "fill the pipe" and slows down velocity.

I would stick with a 90mm TB & the elbow,
Here's a tip, re-drill the elbow's mounting holes so you can turn it towards the passenger tire, this will fix needing a huge cowl hood and will give you more room to run the intake piping.

sorry, not much of an artist...lol

The low profile elbow clears stock cowl and hood, so no cutting will be needed.

While that is a lovely picture, it helps me little. Do you have anything contructive to add to this conversation?

It should help you go faster, I thought that's what this thread was about?

Good sir you seem to be confused, I did not mention going faster anywhere in this lovely ole thread here. I am just concerned with making as little boost as I can.

What about something like this. You wont run into any clearance issues with the stock hood either

http://i33.photobucket.com/albums/d9...s/IMAG0152.jpg

or maybe Nitrous Outlets elbow (victor e manifold in the pic)
http://farm5.static.flickr.com/4020/...324526c7b7.jpg

Just throwing them out there. Dont really know too much about single plane set-ups but both of these set-ups are on some fast lt1s.

It could work, but again, the issue is, I already have a low profile elbow, not concerned with cutting things to make it all work, so I don't want to redo the setup with new stuff if its not a large improvement over current setup.

Still waiting for an answer on intake flow usefulness versus head actual useage.

im all srsness, if you really wanted to go with a 1 off custom elbow based of a design youve seen, do your engineering magic and get the specs of it and my pops can whip you one up.

what are the flow #'s on int/ex of your heads?

263 intake and 206 exhaust, max ported stock castings for now, as I cannot afford some Brodix heads now

Basically this is more complicated than just taking the numbers you are using and dividing or generally comparing CFM #s. You need to look at the CFM for one chamber at its max and assume a % for the other cylinders. For instance, one of the valves for a given cylinder is at its max lift which will have a particular CFM. The other 3 cylinders with open intake valves with be at different lift and flowing different CFM. The largest number of the 4 cylinders with open intake valves is what your intake needs to supply.

There are other factors but that's the just IMO.

Assuming the following:

Max cylinder head flow - 250? + 180 + 130 + 100 = 660CFM

The assumption above would be for the 4 cylinders at various lift values but I basically guessed lol. My assumption is your intake mani ports will outflow the heads you will have on this thing so the restriction will be in the heads which you already know.