I don't post much on H-T or online much, but do read a lot. I've had this CB7 for 8+ years and the past 2 summers the car has been turbo. I still consider myself a newbie and reading is learning, but wanted some random opinions on where to go from here. Here is the general setup I run:

JDM H22A engine
Skunk2 intake manifold
Darton sleeves
Eagle H rods
Arias forged pistons (8:5:1)
Cometic head gasket
ARP main studs
Cometic lower engine gasket kit
Endyne oil pump
Greddy timing belt
Greddy balancer belt
H22A 68mm throttle body
MSD Ignition system
Re-surfaced flywheel
Bully stage 4 clutch
Walbro 255lph fuel pump
Full A/C delete
3" full exhaust (no cat)
ESP engine mounts
ESP front lower traction bar
ESP alternator relocation bracket

GT35R Turbo (.70)
Mishimoto Intercooler
Mishimoto half radiator
Mishimoto slim radiator fan
Tail 50mm BOV
Tail 44mm WG
Top Mount 44mm Turbo manifold
Precision 880CC Low Impedance injectors
GM 3bar map sensor
S300 V2 ECU with boost control


With this setup I am making max 410WHP/296WTQ @ 17PSI. The bottom end was built by a professional machine shop, the car tuned by a professional tuner. From what I know the next steps to make more power should be something like:
- larger injectors 1000CC
- larger fuel pump (325lph+)
- meth install

I'm in the process of building a better transmission for it, and someone mentioned building a head for the block with Skunk2 Pro1 Cams would help, but I think this would only affect high rpm space (I'm not sure). Thoughts are welcome on how to progress from here for more power.

Thanks

 

pistons are a little low. i hated my cometic headgasket. what duty cycle are you at now.

 

Sorry, I do not know. I know it was dialed back a bit as I kept hitting boost cutoff, but I have yet to connect SManager to the ECU myself and check things out. (I only drive the car several times in the summer, i work on it more than i drive it)

 

i would switch to ethanol run a walbro 450lph with some id2000. 8an feed with stock feed as return and call it a day as far as fuel goes.

 

8.5:1

Please, come join us in the 21st century. We have cookies, milk, and better powerbands.

 

Get some thermal sleeving over those water lines. They'll burn through that turbine housing in short order. Get a turbo blanket while you're at it. Seriously talking here.

 

"i would switch to ethanol run a walbro 450lph with some id2000. 8an feed with stock feed as return and call it a day as far as fuel goes."

Thanks. Great advice. I thought id1000 would do the trick.

"8.5:1
Please, come join us in the 21st century. We have cookies, milk, and better powerbands."

Too newbie to know what you are getting at. I always thought low compression was best for high boost applications.


"Get some thermal sleeving over those water lines. They'll burn through that turbine housing in short order. Get a turbo blanket while you're at it. Seriously talking here."

Great advice, will look into this for sure! I'm assuming you are referring to the water lines feeding the turbo.



I was more looking for advice what should be added/changed for higher HP numbers here. Hoping to go for over 500HP next summer and wanted to start buying parts.

 

Safety is more of a concern than silly dyno numbers. You want to start buying parts, get the ones that keep the turbo and the engine in one piece..

The pistons are what that are. Can't do much about that, but you know next time.

 

with the technology we have now in engine management and further understanding of turbo systems, lowering compression so much is just completely unnecessary and it negatively effects every aspect in regards to engine response, turbo response, acceleration...etc. We have a lot more control over both systems nowadays.

 

Well, good to know. So you're saying a 9:1 or higher compression piston would of easily done the trick? Or there are better pistons for this application?

 

thats exactly what he was getting at, low comp for boost is the old way of thinking, should do a lot better with a higher compression ratio

 

my new turbo build which will be a street car is close to 11:1

now that is a little higher than I had originally planned (running a F20b head which has a smaller chamber) but I have 10.5:1 pistons.

plenty of stock engines are pushing beyond 400whp and they are what? 10:1-11:1? so why wouldn't a forged bottom end be able to do that?

all lowering the compression does is increase the amount of work the turbo needs to do in order to accomplish the same thing a higher compression engine could do on less and mean while get better response and likely better gas mileage.

 

I'm assuming low comp. pistons are something one would use if they were trying to hit 700HP+ ? or is this simply a thing of the past?

 

its an obsolete way of thinking. a lot of the SFWD guys are 10:1+

 

Interesting. So where to go from here??

 

Thing of the past..

 

Its a mustang dyno... will read low? But yes does seem low on both hp and torque try and different dynojet dyno for 17 psi... my big wheel 50 trim did just as good but dyno tomato tomatoe

Yea it's a 95mm... but H23V Built 9.6-1 compresson stock cams. 255 hp pump/stock lines 880cc precision inj... 50 trim big wheel T3/T4 411 hp 330 trq @ 15 psi . Same setup SC6176e @ 15 psi 473 trq 373 trq. Pump gas 91 Dynapack. I believe was around 90% on duty cycle

95mm H23V 9.6-1 compression type s/euro r cams with PS. Same manifold setup. T46266. -6 feed 340 stealth aero, stock line back. 1150cc grams. Pump gas 91. 15 psi 475 whp 373 trq on dynojet this time. So would of read lil higher on his Dynapack. 67% duty cycle. I am also methanol injection devils own but have yet to have it in use.

255 and stock lines should support 500-550whp.

I would step up to upgraded fuel pump wires 10 gauge/relay and 340+ pump... -6 fuel feed will only help...

I would step up injectors to atleast 1000cc... can get the trusty 1000ids or cheap out and get 1100 precisions.... Saturated/High Impedence only way to fly

I would step up the turbo to a T4.... H22's after 600 hp seem to need a T4... H motors need to breath. T3 becomes restrictive at a point.

Your GT35R should of realiscally probably made same hp and trq to the wheels as my T46266 and SC6176e. GT35R more like a 6262 believe...
H22A friends GT35R T3 made 480 hp and 370 trq at 17 psi pump

 

Orange is the new black jk... but 9-1 is the new 8.5-1

Running higher compression will better improve throttle response and down low power especially on lower boost levels... and spool up time

Personally if trying to get upwards of 30 psi or more... anything more then 10-1 would get finicky... becomes harder to tune etc.

Yes guys taking the motors to the max are running higher compression... but your accord isn't going to be a outlaw or sfwd.

No way would I do a rebuild to bump up compression if your compression test is good and 190 across...

 

Yea if the engine is freshly built don't take it apart.

Is the static compression ratio a bit low by today's standards? Yes to a point
Will it still make power? Yes

Don't worry, just get a proper tune and drive the damn thing. If the engine has to be torn down in the future then I would consider a change of piston.

 

Well thanks everyone. This is what I was looking to hear.

Thanks ESP.net (if you are the ESP guy i run your mounts, traction bar, and alt relocation, cheers to you). Interesting to see other H22A setups with the same turbo's and PSI hitting different numbers. Goes to show not all identical setups are the same. The only thing that confused me on what you noted was the 1000CC high impedance. Currently I currently have low impedance and I thought this was a OBDI vs OBDII thing, I'll have to read up on if there is 1000CC low impedance or convert to a high impedance; again just not something I've read up on. I'd be happy with 480, but over 500 would be the next goal.

Thanks Wantboost. Agreed with what you said.


So the next plan is to start buying parts over the winter.
- 1000CC injectors
- probably go with braided 6an fuel line
- larger fuel pump and some meth
- turbo blanket
- start rebuilding the head down the road

Currently the weak link is the transmission so that is getting attention now. Rebuilding a T2T4 transmission and swapping a F23 5th gears into it along with some carbon synchros. The other issue is putting this power to the ground. While a full LSD tranny will help the max tires that can fit on a cb7 are 225/50/17, and currently I run 215/45/17 as they have the look I want. So I'll be getting into boost by gear down the road it looks like too.


Thanks everyone for the help.

 

In addition to the blanket (PTP makes quality blankets), Shodan recommended some heat sleeving for the water lines. DEI makes some as well as many other generic brands that work just as well (Jegs / Summit)

 

Thanks, I tried looking for these last time it was mentioned here but I couldn't find them. Let me try looking again...

 

Go to DEI and get the part numbers for the thermal sleeving. Then head to Summit Racing .com with those numbers and search for them. Easy.

You're a big boy.. you can find it.

 

Yes same guy.

I got my turbo blanket from Real Street. Good price good quality. Any turbo that is or smaller T4 .81 can run a T3 blanket... smaller and tighter. What I run on my T4 .81. I only thermal wrap turbo/blanket, downpipe and dumptube till after oil pan. Thermal wrapping turbo manifold personally I think just makes manifold welds possibly weaker with the trapped heat and weight and just turns it into a sauna type deal.

As far as injectors yes OBD1 Prelude/Accord use Low Impedence/Peak and Hold injectors. These require the resistor box. All the trick injectors are High Impedence/Saturated/OBD2. It is as simple as un plugging your resistor box and tossing it out. Then from there use the box connector and run about 6" of pigtail which usually is all the way to box. Then cut. Then will connect all wires/soder together. Made your own adapter/conversion. Then wrap up and good to go. But read up online good write ups on how to delete resistor box. You will obviously need a retune soon as you go with High impedenct/Saturated injectors. Wont fire up with a tune of Low Impdedence/Peak and Hold. All forms of tunable ecu's hondata/aem etc etc can use either or type of injectors no matter what obd.

Also do compression test just to see where your at now... I usually do them every 2 months or so depending how I drive them/often to see whats up.


As far as the transmissions go no matter H/F with or not with LSD.... even carbon synchro'd up. I have a M2B4 JDM LSD fresh rebuld carbon synchro's and sleeve. The limitations seems to be in the area of 400+ ft lbs of torque and 550 whp. Anything around there it is a crapshoot...Have a friend that has gone probably as much as 20 H22 transmissions taking it to the limitations... so expect the worst and plan ahead... especially in a heavier car such as accord/prelude. Anything more will want and need an aftermarket LSD and custom gears which gets real spendy. Aftermarket LSD and carbon synchro'd up and a 5th gear cuff may get you to 600 but no 5th gear obviously with a cuff.

Seems your not going to try and go too crazy on power so you should be okay on the trans. I wouldn't upgrade the piping size of intercooler unless going crazy... just probably not worth effort but most like 2.5" on hot side and 3" on cold.

 

The only issue with blankets is that high EGTs actually cause metallurgical degradation of the turbine housing material... So just keep an eye on things.

It typically starts from the inside out with the inner surface of the volute flaking off and progresses from there. It's a fairly common problem with rotaries but they have crazy high EGTs. Just be mindful and make it a point to regularly inspect the turbine housing