Turbo-charged

mild build h22. stock head, stock cams, stock intake manifold. 2.5 inch downpipe, greddy ic piping with their cast "pancake" style intercooler pipe. lovefab manifold with 38mm wastegate. the ONLY change made between the 2 runs shown is the low power graph was with a 2.5 inch exhaust and the higher hp graph was a 3 inch exhaust that me and fred made. 3 inch stainless, tig welded.

the slight midrange dip is a rich air/fuel spot...but unfortunatly the MSD took a crap and i was unable to clean it up right there. thanks to Jeff Evans for educating me on some of the previous MSD problems he has had to help identify the problem.

both dyno runs are done at the exact same boost level, 15psi. i also pulled out a little bit of timing on the higher hp graph.

ive done before and after testing on exhausts previously, but have never seen gains as good as seen here.

ignore the 50 runs....this car has had like 400 differnt set ups on it over the years and they are all just kept in the same file.

boostincoupe

nice!

Dragline

I bet the customer was happy with that

Turbocivic94

nice gains

archmage

I wonder how it'd be with a 3" DP ?

0Synapse Motorsport

Great comparision

non-VTEC

wow.......i think i will deffinatly change my 2.5" to 3" now.......

95GSRTT

It wasnt stated but just implyed, but was this with the same 2.5inch downpipe?

Turbo-charged

yes this is with the same 2.5 inch downpipe, it was not changed.

i'd love to do a 3 inch downpipe for him as well but it wont fit. car has a/c power steering, etc etc. we had to custom fab him a front engine mount too. whoever did fab work on the car previosuly tried to make a mount that bolted to the slave cylinder and it ripped the threads out and broke a peice off of the trans. needless to say there isnt much room down there anymore. IC piping from the turbo to the intercooler is only 2 inch piping.

id really like to experiment with intake manifolds on this car

jsprelude

I just want to thank Joe for all the work he has done on the Prelude! Topclass work and a super nice guy! Just for the record here is the current setup
H22a
*AEBS sleeves
*Arias 9:01 89mm pistons
*Crower Rods
*Micro balanced crank
*Ported head by Endyne 3 angle valve job
*ARP head studs
*Crower dual valve springs/ Retainers
*Ferrea Valves
*Love Fab Manifold
*Precision SC61 t3/t4
*38 mm Tial wastegate
*Koyo radiator
*Greddy intercooler
*Greddy Profect B spec boost controller
*TurboXS type H blowoff valve
*Skunk2 cam gears
*hondata s100 with boost option
*AEM underdrive pulleys
*msd sci ignition system
*msd blaster 2 coil
*Custom 3 inch turbo catback dual Exhaust
*custom 2.5 inch downpipe
*str 70mm throttle body
*custom ported and polished type s manifold
*walboro 255 fuel pump

Thanks again Joe!





Modified by jsprelude at 12:59 PM 2/17/2006

Under_Pressure

Very nice gains!

Now can u plz do it again but this time open downpipe on both! That would be awesome info to look at!

Turbo-charged

i think if we did open downpipe it wouldnt give very good results on how well each exhaust performed


i assume your asking to do testing between an open 2.5 and 3 inch downpipes rather than exhausts?

send me a junk Mild steel downpipe flange and a couple mandrel mild steel 2.5 bends and i'll gladely do a test (i only stock stainless). im putting together a winter beater stock LS motor right now and i'd be more than glad to do a test if you want....i'll even send the 2.5 inch downpipe back to you after i fab it up.

95GSRTT

I would have never thought that there would be THAT big of a change between the 2. Was there any kind of caved in cat or anything? Either way, glad I still have a 3" exhaust for my future turbo plans then lol. Just gotta make sure to get a lot of resonators lol. Good work though!

Under_Pressure

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Turbo-charged &raquo;</TD></TR><TR><TD CLASS="quote">i think if we did open downpipe it wouldnt give very good results on how well each exhaust performed


i assume your asking to do testing between an open 2.5 and 3 inch downpipes rather than exhausts?

send me a junk Mild steel downpipe flange and a couple mandrel mild steel 2.5 bends and i'll gladely do a test (i only stock stainless). im putting together a winter beater stock LS motor right now and i'd be more than glad to do a test if you want....i'll even send the 2.5 inch downpipe back to you after i fab it up.</TD></TR></TABLE>

wait this wasn't your car! dam ya i just meant unbolt the downpipe form the exhaust to see what gains where yielded.

D@nnY

do you have a rpm based graph? I dont see how you gained 50 hp in the lowere portion if it wasnt even in boost

Turbo-charged

so another words do 2.5 inch open downpipe vs. 2.5 dp and 3 inch exhaust?

on my personal car i had 3 inch downpipe and 3 inch exhaust. i lost 60 horsepower by unbolting the exhaust (but the air fuel went off the chart rich) the air fuel was so bad that i didnt feel like messing with it so i just put the exhaust back on. not to mention the 2 step in my car is so loud and violent...that with open downpipe i can feel the downpipe exploding under my seat and it kinda hurt my *****.....so i decided i liked having an exhaust haha

Turbo-charged

when i uploaded it i wasnt paying attention and loaded mph on accident....this turbo spools almost instantly...it was def. in boost in the lower part of the graph.

i love sc61's on h22's.

Dragline

Ya I don't see why you couldn't be in boost A 55mph..

SlowB16si

dang i cant wait to upgrade my shitty 2.25" exhaust to 3".

all go teg

those are some impressive numbers, id like to see if there would be the same gains for a set up that's not using as much boost

Dublocivic

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote"> downpipe exploding under my seat and it kinda hurt my *****.....</TD></TR></TABLE>

hahaha

turncoat

Looks like boost creep at the top end, I'll bet that 38mm Tial isn't keeping up with the amount of flow it has to deal with.

impressive though...

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Turbo-charged &raquo;</TD></TR><TR><TD CLASS="quote">... 38mm wastegate.

</TD></TR></TABLE>

thursday

i wonder how much the timing change affected the comparison. Nice numbers though

Turbo-charged

not sure on the HP difference with the timing adjustment. peak torque went down just a little. if i remember correctly this car was in the 305-310ft/lbs range.

jsprelude

Hey joe you have any pics of the exhaust??