I am going to have my IM off this week for a throttle body/port matching and i was hoping i would be able to do some quick iab tricks to maybe pick up some power or throttle response...

I know 2lude4u's thread, so none of that stuff is news to me, but how about taking out the iab plate completely, that makes a smaller runner more suited for my stock rpm range....

the motor set up is just a jdm h22, j's racing intake, 70mm str t-body, rmf header, 60mm catback, tuned s200....

thanks for the imput boys

 

bump it up...

 

i just took out the valves. Left the shaft and everything in for now until i get time to take it out and weld the holes shut. not really much else you can do to it.

btw, did you get your motor tuned with the RMF header?

 

not yet, this is all going together next week, hopefully tuning next saturday at RLZ, i will keep everyone updated....

anyone with any other ideas?


Modified by mgags7 at 11:13 AM 9/16/2005

 

id leave them in. My bottom end sucked *** when my IABs were disabled.

 

i had figured as much....we will see what brad thinks when i get there, may end up taking em out or i dont know....either way they will be thrown into the tuning.....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">

...I know 2lude4u's thread, so none of that stuff is news to me, but how about taking out the iab plate completely, that makes a smaller runner more suited for my stock rpm range....
</TD></TR></TABLE>

A shorter runner will be more suited for a higher rev range.

for example: an 11 inch runner length...

For 2nd harmonic, RPM range is from 10680 to 12960 with a pulse strength of 10 percent
For 3rd harmonic, RPM range is from 8025 to 9171 with a pulse strength of 7 percent
For 4th harmonic, RPM range is from 6256 to 6996 with a pulse strength of 4 percent


compared to a a 14" runner is:

For 2nd harmonic, RPM range is from 8702 to 10560 with a pulse strength of 10 percent
For 3rd harmonic, RPM range is from 6539 to 7473 with a pulse strength of 7 percent
For 4th harmonic, RPM range is from 5098 to 5701 with a pulse strength of 4 percent


You can see how drastically 3" can change the RPM range.


BTW, the length of the runner starts at the back of the valve seat.

 

so optimally i would want the 2nd harmonic in my higher rev range, and the rest lower down....

good info, thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">so optimally i would want the 2nd harmonic in my higher rev range, and the rest lower down....

good info, thanks</TD></TR></TABLE> Yes. Also, plenum volume should equal the displacement of your engine. This is not possible with the stock manifold, but if you were to use 2 or 3 IAB plates hollowed out and stacked together plenum volume will increase.

 

hmmm.....sounds interesting....

anyone have any extra iab plates?

edit: thanks 2.6

 

good info

 

My setup netted some strange results. I am using a hollowed out manifold that has 2 butterfly plates that are gutted/hollowed also. Prior to that I had a stock manifold with slight porting to match my 64mm throttle body and porting that went 1 1/2" into the runners.

It took me alot of tuning to get the manifold at a positive. I adjusted my intake cam +1 degree, added timing down low and made the AFR a solid 12.7-12.8 across the board. I actually gained about 5lb/ft of torque on the low-end. Picked up 0.1 lb/ft of peak torque and &lt;1 peak whp. The graphs of my new manifold and old manifold kept crossing in several places

Here is the dyno graph. Dark blue is the manifold that's been gutted w/ 2 IAB plates stacked. The light blue is the OEM manifold.



Modified by precord96 at 6:29 PM 9/17/2005

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 2point6 &raquo;</TD></TR><TR><TD CLASS="quote"> Yes. Also, plenum volume should equal the displacement of your engine. This is not possible with the stock manifold, but if you were to use 2 or 3 IAB plates hollowed out and stacked together plenum volume will increase.</TD></TR></TABLE>

Could you explain to me the reasoning behind this?

Also, what is technically considered the plenum? I.E.-how would i go about calculating plenum volume?

 

how would the results differ on a turboed car?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 2point6 &raquo;</TD></TR><TR><TD CLASS="quote"> Yes. Also, plenum volume should equal the displacement of your engine. This is not possible with the stock manifold, but if you were to use 2 or 3 IAB plates hollowed out and stacked together plenum volume will increase.</TD></TR></TABLE>I would like to know the theory behind this. It sounds as if your talking about making velocity stacks... old V8 trick.

 

stop wasting your time, i dont see how the euro r and the skunk2 IM arent two clearly good options, any of this intake manifolds side by side would completly reveal that both are a better design to begin with. i wouldnt wanna bother taking of my manifold to remove those butterflys and putting the stock p.o.s. back on.

 

DC West someone would want to do this because you can buy stacking plates from blacktrax for $30 instead of $350 sk2 or $220 plus alot of labor euro r

2 point 6 would you add the 2-3 plates with the butterflies in or out. I remember seing a post where you mentioned something along the lines of modifing a stock manifold with better results than the euro r. Correct me if I am wrong. Would you care to share what you were talking about

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boostlude &raquo;</TD></TR><TR><TD CLASS="quote">DC West someone would want to do this because you can buy stacking plates from blacktrax for $30 instead of $350 sk2 or $220 plus alot of labor euro r

2 point 6 would you add the 2-3 plates with the butterflies in or out. I remember seing a post where you mentioned something along the lines of modifing a stock manifold with better results than the euro r. Correct me if I am wrong. Would you care to share what you were talking about
</TD></TR></TABLE>

Up

 

I would add atleast 2 plates with the centers cut out completely. However, you need to modify the bottom portion of the manifold to match your desired RPM range as well. This is a lot of work and most people won't take the time.


Modified by 2point6 at 11:24 AM 9/25/2005

 

I was thinking the bend in the lower portion in the manifold is almost a 90 degree bend and that could be smoothed out to be a better transition. The runners change from going horizontal to vertical so abruptly into the plenum. I was thinking of smooting this transition out with a grinder and testing the results.

 

the stock bottom half can definitely be used....

brad @ rlz is making a one-off manifold for my friends h22 build, most likely he will be using the stock bottom half....not quite sure what hes gonna grind out, but we were down there while i was getting tuned and brad showed us a plate he made for the plenum, handmade perfection, freakin amazing....

my friend (jd3jdm)'s build will be done in a month or two, it is gonna be real sick, so we will see from that if any of this stuff is gonna really work well.....

 

^^yeah I can't wait...
You guys will see soon!
Don't let any cats out of the bag about the build yet