I have a greddy kit on my d16y7, I'm considering a y8 mani swap, but I've heard gains aren't too great for NA people. I did a search and was discouraged to find this out, but there were no posts that I could find that were turbo-related. So...

What kind of gain can I expect for a y8 intake manifold swap for my d16y7 on 8psi of boost? Thanks for any input.

 

From what I'm seen/heard ( not real scientic proof or anything ).
Z6 = N/A
Y8 = turbo ( has a bigger pletuim/bubble thingy )
A6 = cheap for first timer MPFI swap guys.

I'd bet you'd see a descent increase in top=end power no matter what intake you trade for the Y7 one...

I'd bet you'd see a better HP increase with swapping in fresh plugs everytime you drive ( of course that's silly).

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 89dxhunchback &raquo;</TD></TR><TR><TD CLASS="quote">Z6 = N/A</TD></TR></TABLE>
Naturally Aspirated? Or Not Applicable?

What about swapping a Z6 head for a Y8 head? Naturally Aspirated? or Turbo?
-PHiZ

 

It's gain over the y7 for sure. How much I'm not sure but with boost in the picture it would help quite a bit.

 

lol @ sohc.

With any manifold you change your 7 out for you'll see an increase. its just if 2-8whp is that much to you? why not just get a skunk2 and get 12-18?

-ryan

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tegasaurus &raquo;</TD></TR><TR><TD CLASS="quote">lol @ sohc.

With any manifold you change your 7 out for you'll see an increase. its just if 2-8whp is that much to you? why not just get a skunk2 and get 12-18?

-ryan</TD></TR></TABLE>


I call BS on the Shunk @ giving 12-18 Hp

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by infinatenexus &raquo;</TD></TR><TR><TD CLASS="quote">


I call BS on the Shunk @ giving 12-18 Hp</TD></TR></TABLE>

keep in mind this is a turbocharged car, son... from a y7 intake manifold to a s2 would be drasticasaurus

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tegasaurus &raquo;</TD></TR><TR><TD CLASS="quote">

keep in mind this is a turbocharged car, son... from a y7 intake manifold to a s2 would be drasticasaurus</TD></TR></TABLE>


lmao@son.....

 

I swapped out the Y7 manifold from a d16a...umm whatever manifold the 90 Si had in it. This is on my daily beater and I dont know if it gained anything---nor do I care, lol.

 

I swapped the Y8 on my friend's Y7, made a nice difference on the ***-dyno over 5k, noticeable on a DX

 

No for real, someone drop some science on long vs short runners and plenum volume on NA and FI setups....
-PHiZ

 

without hardXcore science crap, the longer and "thinner" (minimum is the size of the intake port) the runner the lower your power will come. the shorter and thicker it is, the higher up it will come.

true in cases of n/a and fi

-ryan

 

From a flow stand point, the stock z6 intake manifold flows the most cfm out of any of the oem d series manifolds. I did this test on a superflow flow bench. Let me see if i can find the charts.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by norcalcrx &raquo;</TD></TR><TR><TD CLASS="quote">From a flow stand point, the stock z6 intake manifold flows the most cfm out of any of the oem d series manifolds. I did this test on a superflow flow bench. Let me see if i can find the charts.</TD></TR></TABLE>

WOW. is raw CFMs the only criteria we evaluate IMs on? Cause I've always heard it told that the D16Z6 head flows the best and the D16Y8 IM flows the best.

Besides raw CFM, there is velocity to take into account, and I believe "laminar" flow??? How does plenum size act on airflow?
-PHiZ

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PHiZ &raquo;</TD></TR><TR><TD CLASS="quote">

WOW. is raw CFMs the only criteria we evaluate IMs on? Cause I've always heard it told that the D16Z6 head flows the best and the D16Y8 IM flows the best.

Besides raw CFM, there is velocity to take into account, and I believe "laminar" flow??? How does plenum size act on airflow?
-PHiZ</TD></TR></TABLE>

A6 head flows the best by a good margin.

Running a Y8 intake on a D16Z6 @ 10 psi, feels about the same as a stock high mileage ZC with the "poorer" D16A1 intake manifold on it did at 7 psi.

I could really give a flying woo-hoo less about cfm flowed until it presents a restriction to compressor efficiency. Your questions in re quality of and characteristics of flow, however, are entirely valid. I'd hate to be sending a significant amount more air down one particular runner as it would be running leaner than your wideband readings suggested.

 

hey how about the fact that you'll be able to run a normal strut bar with a y8 over y7 mani.

the y7 is really an odd design.

but yeah, from my research, the z6 mani beats out the y8 for allmotor, just by a small ammount though.

but the y8 is probly great for turbo,
also if your already obdII, you dont want to go back to an obdI mani