Intakes

[85boostbox]

What is your opinion on the 1 piece and 2 piece intakes. Been doing some reading and comparing so of our intakes to some of the most efficient engines of all time practically. A lot of similarities but want to find out what you guys think???

[johnl]

I like long runners, no data, just from observing what appears to work in naturally aspirated engines, and by that comparison neither the 2 or 1 piece runner appears to be long enough.

[85boostbox]

I have been doing A LOT of reading lately. Preparing my build pretty much. See I think that is where people make mistakes is right there. A turbo engine and a naturally aspirated engine are 2 very different animals.

I have noticed one VERY key difference which is a big difference inbetween the 1 piece and 2 piece outside of the obvious. And if you look at Formula One cars that were turbocharged back in the day you will see the similarity.

All about efficiency...

[Warren Stramer]

A turbo engine and a naturally aspirated engine are 2 very different animals.

I'm curious, what or who led you to that conclusion? Not to be argumentative, but that is categorically false.

[thedon809]

I'm curious, what or who led you to that conclusion? Not to be argumentative, but that is categorically false.

I never bought what people said about turbo vs n/a being way different.

[85boostbox]

I'm curious, what or who led you to that conclusion? Not to be argumentative, but that is categorically false.

No its not. Would you shove a high overlap cam into a turbo engine? No. Timing? Would you advance the timing as much in a N/A engine as you would a turbo engine? No. Would you agree that there is a lot less room for error than there is for a turbo engine. I would. Typically you would port heads differently against a turbo and N/A. Anything that has forced induction you have to look at stuff from a different angle correct?

All of this stuff makes building a turbo engine a different animal...


Paul

[Warren Stramer]

No its not. Would you shove a high overlap cam into a turbo engine?

Yes, and many of us do.and maybe we should define "high overlap"

Timing? Would you advance the timing as much in a N/A engine as you would a turbo engine? No.

Possibly, depends on the cyl pressure, (static CR, dynamic CR, valve events, expected peak HP rpm and Fuel type) but those would be a TUNING decisions.

Would you agree that there is a lot less room for error than there is for a turbo engine. I would.

I'm not sure if you mean tuning error, or design error??

Typically you would port heads differently against a turbo and N/A.

why would you think that? What would need to be different in port design? and why?

Anything that has forced induction you have to look at stuff from a different angle correct?
All of this stuff makes building a turbo engine a different animal...

Well yes, no, and maybe. I'm trying to get a point across that all IC engines are essentially the same, turbo or NA, except for the DENSITY OF THE AIR BEING INGESTED, and in the case of a turbocharged engine, a turbine in the exhaust stream, which can be either a huge restriction, or not. and the more it is not, then the more the two engines become the same.
A well designed turbocharged engine is no different than a NA engine running in a very dense atmosphere.
there are some design nuances to be sure, but not so much as to make them "a very different animal."

[turbovanman²]

No its not. Would you shove a high overlap cam into a turbo engine? No. Timing? Would you advance the timing as much in a N/A engine as you would a turbo engine? No. Would you agree that there is a lot less room for error than there is for a turbo engine. I would. Typically you would port heads differently against a turbo and N/A. Anything that has forced induction you have to look at stuff from a different angle correct?

All of this stuff makes building a turbo engine a different animal...


Paul

You'd be wrong in that assumption. Talk to guys/shops like Lingenfelter, Dutweiler etc, they all agree a good ported n/a head is a great boosted head.

[fishcleaner]

I went with a 2 piece because the injectors point more direct to the valve, but after looking at some custom race intakes, they have the injectors pointing to the bottom of the runner, maybe creating a curtain of fuel that the air has to go thru. If you are going stock, I would opt for the 2 piece, that's what Shelby did.

[contraption22]

, I would opt for the 2 piece, that's what Shelby did.

I don't really think Shelby opted for anything. He used what Chrysler had available.

I think the two piece should work better going by theory, by what's on paper, and by just looking at the two designs. The fact of the matter is most of the people will never optimize their mild combinations to the point where a significant difference in performance could be measured. And those with more radical setups have moved to either significantly modified factory intakes or nearly clean-sheet redesigns.

[85boostbox]

I don't really think Shelby opted for anything. He used what Chrysler had available.

Chrysler didnt have a 2 piece in 1986. It was Shelby built and designed.

[contraption22]

Chrysler didnt have a 2 piece in 1986. It was Shelby built and designed.

It was Chrysler built and designed. The GLHS received them as did all early TII's.

[lengel]

I could be way off on this, but a one piece has to be a lot cheaper to manufacture then a two piece. This is why I think Chrysler went to a one piece.

[85boostbox]

Now onto what I want to say while my stupid computer decides to act right...


I have been studying a lot into Porsche and Cosworth turbo designs and what they do to get so much power out of a small engine. They OBVIOUSLY have the turbo world down pat. Now look at the F1 cars that Cosworth produces. Look at the intake and how it is designed. Notice how the throttle body tract is angled almost directly at the center of the runners and the intake runners. Now look at the 1 piece. Notice anything similiar. Look at the 2 piece. Straight... Runners are also straight.

Now look at the Maserati TC 16V. Look at the intake. Notice a similarity with the runners inbetween the 1 piece and that intake. And the throttle body tract is somewhat similiar as well. Goes up and then directs down. They are designing there intakes the SAME way now and days. They MUST be doing something right. Look at cosworths site and look at there aftermarket intakes. They have the throttle body tract aiming the same way.

---------- Post added at 09:28 PM ---------- Previous post was at 09:24 PM ----------

We have literally hammered this topic to death, but the 2 piece is far superior to the one piece, even if flow numbers are fairly close, one has to see inside a one piece to see what a pile of junk it truly is.

Flow numbers mean NOTHING when there is no velocity. Turbgocharging is ALL about velocity and flow.

[85boostbox]

I will say this. A custom intake will out do as long as enough thought goes into it a stock piece any day.

Now onto what Shelby did. Yes he created the 2 piece. But if it was so well with efficiency why didn't Chrysler stick with it. And why didn't Shelby continue to use it after 87. I would imagine if it was so efficient he would have especially used it on the 89 csx. I think there was more engineering that went into the 1 price then what directly meets the eye. Remember turbocharging is all about velocity and efficiency. They obviously coincide with each other.

[cordes]

I think it has been proven out that the two piece intake is superior to the one piece. However that is not to say that great power can't be made through a one piece if something mild is desired.

[turbovanman²]

We have literally hammered this topic to death, but the 2 piece is far superior to the one piece, even if flow numbers are fairly close, one has to see inside a one piece to see what a pile of junk it truly is.

[Khajjathefang]

Its 20freaking12 and people are still clinging to the notion that the 1 piece was anywhere near the 2 in performance? Guys, people have cut these things up, search it. Its a giant pile of dook on the inside. The only place they are better is when heavily modded with a cut down two inch runner, huge plenum, and bigger neck.

btdubs: do you really think a harmonic bounce is going to affect air when its being crammed in at 2+ atmospheres? Short runners, short as you can get.

[roachjuice]

I honestly don't think it matters much on a mild setup. Has anyone EVER did a back to back comparison between the 1 and 2 piece? Afaik no one has done it yet with no other changes.

[85boostbox]

Its 20freaking12 and people are still clinging to the notion that the 1 piece was anywhere near the 2 in performance? Guys, people have cut these things up, search it. Its a giant pile of dook on the inside. The only place they are better is when heavily modded with a cut down two inch runner, huge plenum, and bigger neck.

btdubs: do you really think a harmonic bounce is going to affect air when its being crammed in at 2+ atmospheres? Short runners, short as you can get.

Cut them up all you want. Look at the engineering aspect.