ok im helping my friend with his gsr and he wants start ordering parts but i just want to go over some things first.....

b18c1
CTR pistons
arp rod bolts
arp head studs
head ported
skunk2 i/m
dc 4-1 header
skunk2 stage 2 cams or rocket m22's....need input on both of these
2.5 in full exhaust
CAI
and just a basic hondata chipped ecu.

just wondering if any1 else has a similar setup and would like to know about both of the cams and injectors will the 240's do or will it need to be upgraded. thanks

 

240cc injectors might be sufficent for that setup, i hope u clay the motor, or turn it over slowly to listen if the valves are hitting the pistons even though i think ctr pistons have valve reliefs in them

 

I would not run those ctr pistons! The compression is too much, run a more practical P30 or PR3.

 

You will need something like hondata to tune with and header with a 2.5 inch collector. If the ctr's yeild a 12:1 compression (or somewhere around there) then that is perfect for the skunk2 stage 2's.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jdmHboy &raquo;</TD></TR><TR><TD CLASS="quote">You will need something like hondata to tune with and header with a 2.5 inch collector. If the ctr's yeild a 12:1 compression (or somewhere around there) then that is perfect for the skunk2 stage 2's.</TD></TR></TABLE>

word!

 

that is so close to my set-up, let us know how it goes.

good luck

 

Heres the compression with those pistons:

P72 head/B18C Block

STD = 12.924594026551906
.25 OS = 12.989047869209281

 

the dc 4-1 is gonna be jdm (2.5")? if not that would bottleneck your piping

 

You will need something like hondata to tune with and header with a 2.5 inch collector. If the ctr's yeild a 12:1 compression (or somewhere around there) then that is perfect for the skunk2 stage 2's.

Yes agree that an upgraded ecu, such as skunk 2 p72 or hondata would be sufficient, and an upgraded valve train ( ti, valves, springs and retainers) to rev higher and get more out of those cams would help as well, but your well on your way

 

excellent choice with the ctr's!!!
your setup is very similar to mine.
i would upgrade those injectors though to at least 290's or 310's.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Runnerdown &raquo;</TD></TR><TR><TD CLASS="quote">Heres the compression with those pistons:

P72 head/B18C Block

STD = 12.924594026551906
.25 OS = 12.989047869209281


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

This is incorrect info

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Runnerdown &raquo;</TD></TR><TR><TD CLASS="quote">Heres the compression with those pistons:

P72 head/B18C Block

STD = 12.924594026551906
.25 OS = 12.989047869209281


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

i wouldnt dare run that on the street

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Runnerdown &raquo;</TD></TR><TR><TD CLASS="quote">Heres the compression with those pistons:

P72 head/B18C Block

STD = 12.924594026551906
.25 OS = 12.989047869209281


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

i REALLY dont think it is that much, i was runing the JDM p30 pistons ( not THAT far off of the PCT(ctr) pistons) and my cr was like 11.5 or so, the ctr pistons are calc wrong on alot of the CR cals out there


he can run them just make sure you get it tuned off the bat( ASAP) and run bigger injectors, i had 440s in my setup alot like yours, and grab some 7 series spark plugs ( one range colder then stock) these are all things straight from my tuners mouth. . . .


EDIT: dont waste your money on a jdm itr header get somethign that will flow better

 

A friend of mine does ~210whp on his mild compression ITR motor. Let me know if we can help you.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by clean rice &raquo;</TD></TR><TR><TD CLASS="quote">This is incorrect info</TD></TR></TABLE>

Actually it might be pretty darn close.

 

I run mine on the street with 93 pump gas does great here are my specs

B18C1 Motor
Block has been hot tanked and bored 0.25
ACL Bearings (Main and Rod Bearings)
SuperTech Stainless Steel valves
Shotpened GSR Rod
CTR O/S Pistons
ARP Rod Bolts
ARP Head Studs
ITR thorttle body
Hondata intake manifold gasket
Skunk2 Stage 2 cam
Skunk2 Cam Gears
Skunk2 valve srings
Skunk2 retaniers
Skunk2 intake manifold
S2000 fuel pump
Lucas 440cc injectors
STR fuel rail
00 JDM ITR header ported inside,welded outside
Car Sound high flow cat 2.5"
2.5 Manga Flow Muffler ( sleeper)
Hondata S200 Tuned by Mase on Honda-Tech

dyno pic

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Runnerdown &raquo;</TD></TR><TR><TD CLASS="quote">Heres the compression with those pistons:

P72 head/B18C Block

STD = 12.924594026551906
.25 OS = 12.989047869209281


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

Where did you get that info??? Seriously, I don't know how people mess up compression calculators... Whatever.

According to C-speed's CR calculator, the compression will depend mostly on the piston-to-deck height of the CTRs.

If PTD Height = 0.020" (which is the same as it would be in a B16B block) then the CR is 12.4:1

If PTD Height = 0.030" then the CR is 12:1 This height would be the lower, stock form of a GSR. I'm betting it would turn out to be 0.020"

The only way to be %100 sure is to measure the PTD Height once the pistons are dropped in your block. Even if the compression ratio turns out to be higher than what you'd like, you can easily fix it with a thicker headgasket. CTR pistons in a GSR block/head combo seem pretty safe to me.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tommy69 &raquo;</TD></TR><TR><TD CLASS="quote">Actually it might be pretty darn close.</TD></TR></TABLE>

Ummm, no.......

 

go P30s! what octane do you plan on running?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by clean rice &raquo;</TD></TR><TR><TD CLASS="quote">Ummm, no....... </TD></TR></TABLE>

Why don't you explain, and provide some info

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MrTodd &raquo;</TD></TR><TR><TD CLASS="quote">Where did you get that info??? Seriously, I don't know how people mess up compression calculators... Whatever.</TD></TR></TABLE>

People do no mess up compression calculators, C-speed is wrong as they do not acknowledge CTR has the biggest compression height.

There is a sticky post in this forum, which lists static compression ratio of every Bseries block/head combination when using PCT pistons.

The research and calculations are right there done by Omniman and Altered.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Runnerdown &raquo;</TD></TR><TR><TD CLASS="quote">I would not run those ctr pistons! The compression is too much, run a more practical P30 or PR3.</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MrTodd &raquo;</TD></TR><TR><TD CLASS="quote">Where did you get that info??? Seriously, I don't know how people mess up compression calculators... Whatever.

According to C-speed's CR calculator, the compression will depend mostly on the piston-to-deck height of the CTRs.

If PTD Height = 0.020" (which is the same as it would be in a B16B block) then the CR is 12.4:1

If PTD Height = 0.030" then the CR is 12:1 This height would be the lower, stock form of a GSR. I'm betting it would turn out to be 0.020"

The only way to be %100 sure is to measure the PTD Height once the pistons are dropped in your block. Even if the compression ratio turns out to be higher than what you'd like, you can easily fix it with a thicker headgasket. CTR pistons in a GSR block/head combo seem pretty safe to me.</TD></TR></TABLE>

That explain it for you Tony?? I know SEVERAL gsr motors personally with ctr pistons in them and they have NO detonation what so ever on pump gas. This is a very do-able combination, even on 91 octane. On ff-squads calculator it comes to 12.3 with an oem headgasket. I know c-speed's is off, but Katman knows what he is talking about.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by clean rice &raquo;</TD></TR><TR><TD CLASS="quote">That explain it for you Tony?? I know SEVERAL gsr motors personally with ctr pistons in them and they have NO detonation what so ever on pump gas. This is a very do-able combination, maybe you outta know wtf you're talking about before you start talking.....I have been reading that post, and it backs the 12.1 compression theory.</TD></TR></TABLE>

My name isn't Tony. I did my reasearch before I started talking, I never said it's not doable, I said the compression ratio is in the high 12s and I'm not the one who doesnt know what I'm talking about.

I asked you to explain, and back up your statement with some info and you didn't.

Gotta give it to you tho.. that avatar matches you 100%.

 

Tommy/Tony same thing. So, you are saying that you can run 12.9 compression on 91 octane? Not likely Tony..........and if you looked at what I quoted then that will back up my opinion. Go to ff-squads calculator, that is accurate as katman knows what he is talking about. Like my avatar huh? Keep staring at it pal!