chrisnick

1997 Accord Coupe
F23A1, never opened.
Prelude H23 eBay Intake tube
Blox aluminum velocity stack
AEM 6" dryflow filter
JVT "long tube" 4-2-1 header
2.25" test pipe+exhaust, 14" x 6" x 2.25" ID Magnaflow muffler
Timmytuning F23A1 chip/map/tune on a P28+ OBD2A to OBD1 jumper
62mm TB port-matched upper
Bisimoto intake manifold gasket
62mm H23A VTEC throttle body
thermal TB gasket
IAT sensor moved to intake piping

Tune is crazy rich past 5K(AFR's in the 10's), and VTEC needs set at about 3200RPM. Lots of power left to be made by dialing stuff in. Going to add a ported/gutted F23 lower plenum/runners, chop up/ modify my H2B PLM 4-2-1 header, 3" exhaust, add the cam gear and retune. Total investment in power mods+engine is about $600. Lots of junkyard diving for this stuff, only the filter/vibrant couplers are new.

Two different B18C1 powered cars with bolt ons/tunes made 140-145whp/115-120whtq on the same dyno under similar conditions within the past week. My car door bangs with both of them. See build thread in signature. Full weight, with a crap launch(2.1 60ft), the car runs 15.06@91-92mph off the limiter in 3rd gear. Daily driver/autocross car.




(not the most recent pic of the engine bay)

v4lu3s

Nice power for bolt ons and a base map

thadon805

iTrader: (3)

Nice power for little investment!

I think a lightweight flywheel + accord euro r/Accord type r transmission would be a VERY nice upgrade for your car. Would make it drive like a totally different car.

Unless, you are planning on boosting. The accord transmission gears are long and perfect for boost. Not to mention the compression ratio is pretty much meant for boost.

chrisnick

Getting a t2w4/exedy stage 1/flywheel over winter, I'll upgrade mounts at the same time. Although the trans isn't technically FSP legal, I'm not running the car at nationals, it's already too fat to be even remotely competitive even at a regional level. Just a fun daily/street car. I'll be happy if I can come close or exceed what Jason(AFAccord) pulled out of his car before he went boost. I'm fairly certain I can get to 175/180whp and close in torque without a cam swap.

I'm already collecting parts for a J build...

PyroProblem

Doesn't sound like hes finished tuning yet if your seeing 10:1 AFR and your vtec transition isn't smooth.
Curious to see how much is gained once the ecu tuning is complete.

chrisnick

It was a map from a friend down in Texas. Everyone's setup is different, I just wanted to see what kind of power it made as is and where it all landed. Still lots of room to improve! I'm not really going to waste my time tuning/money it any further in it's current setup, I'll wait until everything else is on it then retest/tune. Better to just do it once and do it right.

chrisnick

Gotta clean up the runner entry a little bit, but this should make some power! Runners used to extend all the way to the flange and have a plenum "pocket" in the area in front of them, this makes them about 3-4" shorter and the entry will be opened up a bit more for smoother entry. For reference, here's a side by side with an h22 manifold.

Let's just say this thing has serious potential for a street manifold when ported. Yes, the runners are smaller in diameter than the H22's, but for an ideal torque peak in the 4800-5500 range, the F23 just needs a little bit to be just about perfect. A little over 2" square for area. The potentially huge plenum easily rivals that of the H22, this is definitely the choke point as cast which makes the engine draw vacuum and flatline around 5000RPM. The F23 is wider, deeper, but shorter front to back than the H22.








H22 butterflys on F23 lower


Aside from this addition, went with a 2.5" exhaust, swapped in a 93-96 Prelude M2F4 trans, exedy stage 1 clutch, and will be switching to Neptune. I'll update the original pictures.

Tachi

Never would have thought manifold envy would be a thing. That looks like its going to really help that engine out, it's good to see your progress on this build!

chrisnick

Yup, gotta get the runner entry finished this weekend, April 17th is the retune date. After this, I'm cutting up the PLM H2B header I picked up for cheap to see if it'll make some more power. If I can get to 170whp/tq without taking off the head, I'll be plenty happy. If needed, I have a cam gear on the bench to play with the curve.

chrisnick

Cleaned up and ready to go.

Tachi

That is looking really cool! ^_^ I can't wait to see what's gained from the manifold.

Just a though, would there be anything to be gained by building-up half-pyramids of steelstick or jb-weld to smooth those flat areas into the front wall of the manifold?

chrisnick

Probably. Worth it on this? Benefit probably doesn't outweigh effort.

chrisnick

Intake on, egr deleted, and swapped to a no coolant JDM B20 IACV. Idles better. And pulls HARD as F to fuel cut at 6500. I think I'll be revving it to 7000 the way it keeps pulling. Zero loss of torque. Can't wait for Sunday.

Tachi

Now I really regret not being able to make it. What time are you scheduled for the dyno?

chrisnick

In the afternoon, maybe around 3.

chrisnick

Ported and stock side by side. Forgot to post this.

chrisnick

Well, results are in. Ported intake was worth some torque down low, about 10whp near Red line. Played with VTEC engagement and found it worked best around the factory engagement at 2400RPM. Gained an assload or torque under 4000RPM. Final run numbers were a little bit lower due to higher IAT's than the initial run, but you can see the old numbers, ported intake+old tune(crome), and new numbers(neptune). Not a big difference in overall peak numbers, but under the curve is sooo much better than before. 14's should be easy with all the new stuff done. Looks like the factory camshaft is holding it back quite a bit, but 140lbsft of torque at almost any point in the rev range is NOICE.

seelback

Good stuff!!! Nice to se testing done.

chrisnick

Sent an email to Derek at DDTech, time to make some more power.

Tachi

At least get a 1/4 et first. :D