I've got an H22, which will stay naturally aspirated, and i'm going to get some custom exhaust work done, i've got mixed opinions whether to stay at 2.25" or to go to 2.5" what will maximize the flow and keep max power?

 

Depending on how far you go with modifying your h22a, My vote goes to 2.25, unless you plan on really trying to make some power N/A then go 2.5" , but Im betting your best off at 2.25

 

get 60mml....its like 2.37"

 

2.5"

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Eddiebx &raquo;</TD></TR><TR><TD CLASS="quote">2.5"</TD></TR></TABLE>

can you give some examples, like what kinda power i'm planning to go to to make use of the 2.5"

 

2.25 will be good to over 250 whp which is more than you will have.

 

with all the plans i have for this year i wanna try and make 230WHP

 

I urge you then to get a 2.25 , one of the biggest mistakes people make is getting to large of diameter exhaust. Keep that until you get up in the upper 200's then switch over to a 2.5 "

 

i don't plan to make upper 200's with N/A too much money for that

i'm getting another accord to H22-Turbo

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rival12 &raquo;</TD></TR><TR><TD CLASS="quote">i don't plan to make upper 200's with N/A too much money for that

i'm getting another accord to H22-Turbo</TD></TR></TABLE>

why?....if you want another accord, get a dx coupe, strip it, and just boost the F22...keep the H powered one relitivley stock (aka, keep it reliable), and then you'll have the best of both worlds -a full interior, really nice H powered NA daily driver, and a gutted boosted SOHC...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rival12 &raquo;</TD></TR><TR><TD CLASS="quote">can you give some examples, like what kinda power i'm planning to go to to make use of the 2.5"</TD></TR></TABLE>

2.5" is a good size for mildly modded h22s. i've tested them against 2.25 systems, and with the 2.5" you gain a few hp up top in vtec depending on how modded the motor is. but under vtec its pretty much the same between the two.

on more heavily modded h22s, the 2.25 starts to choke the motor abit, so the gains of going to a 2.5 are more apparent.

so basically get the 2.5" because you don't loose any power if your stock, and will be prepared for more mods in teh future.

 

2.25"

 

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

2.5" is a good size for mildly modded h22s. i've tested them against 2.25 systems, and with the 2.5" you gain a few hp up top in vtec depending on how modded the motor is. but under vtec its pretty much the same between the two.

on more heavily modded h22s, the 2.25 starts to choke the motor abit, so the gains of going to a 2.5 are more apparent.

so basically get the 2.5" because you don't loose any power if your stock, and will be prepared for more mods in teh future.</TD></TR></TABLE>


sounds good to me as welll

 

yeah your not gonna go wrong with either one, just 2.5" leaves you some more room to grow.

 

2.5 inch is what the honda/acura tuning book says for a h22, and for boost or Nit it sais add half inch. i have the book in front of me i would i had a scanner so i could out up the chart it has for all honda motors and what size to go with intake and exo.

 

2.5

 

well.....mines is at the shop now and im using a 2.75", gonna see what it does.....

 

sorry to go off topic but what do h22 swapped 5th gen and 6th gens generally run at the track? EX models

BTW 2.5" is good size. When you get the greddy header you should cut off stock collector, and weld 2.5" collector. Run that with 2.5 highflow cat or tpipe. Should flow real good and pull up top.

 

either or will work, if ur going all out and dont mind the noise go for 2.5. i had a 2.25 straight back to a greddy and it was a lil obnoxious sometimes.

 

hey man,
well i got a dx sedan with a 2.5 all the way back and tyhe reason why i got it is because i plan on droppin in the H (in my friends gargae) and boostin it. kind of a waste of money if u get 2.25 then switch over to 2.5 you know?

 

that h22 needs to breathe in vtec...and you really don't see that much of a loss down low with the 2.5...i don't have any experience with 2.5, but stock vs 2.5 just adds so much more power in vtec...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by KTeller8 &raquo;</TD></TR><TR><TD CLASS="quote">2.5 </TD></TR></TABLE>
having to little back pressure is a myth. The better flow, the better performance, its dyno proven. although yes, different diameter pipes and flanges will change your power range. when people say you shouldn't run open header because its bad for your engine because you don't have enough back pressure that's wrong, the huge disadvantage of running open header is on a cold night after you shut off your engine while the engine is still warm cold air can flow up into your head and into one of your open cylinders and cause an instant expansion of the cylinder causing it to seize the cylinder to the cylinder wall.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Nick H &raquo;</TD></TR><TR><TD CLASS="quote">that h22 needs to breathe in vtec...and you really don't see that much of a loss down low with the 2.5...i don't have any experience with 2.5, but stock vs 2.5 just adds so much more power in vtec...</TD></TR></TABLE>

i've dynoed a loss of roughly 10hp across teh board in vtec, from a 2.5 straight through muffler vs an rsx-s muffler(1 7/8"). both used the same 2.5" b-piping, just swapped the rear sections.

this was on a stock block and cammed motor however, so i bet on a stockish h22 the loss would be a bit less, but still apparent none the less.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Eddiebx &raquo;</TD></TR><TR><TD CLASS="quote">
this was on a stock block and cammed motor however, so i bet on a stockish h22 the loss would be a bit less, but still apparent none the less.</TD></TR></TABLE>

So there is a loss in power than from the 2.25" to 2.5"

i think i'll just grab a Greddy Header and go 2.25" to magnaflow.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rival12 &raquo;</TD></TR><TR><TD CLASS="quote">So there is a loss in power than from the 2.25" to 2.5"

i think i'll just grab a Greddy Header and go 2.25" to magnaflow.
</TD></TR></TABLE>

why not get a header w/ a 2.25 or 2.5 collector?.....no sense in spending money on a header and piping if it still bottlenecks at the cat....