So close to running 14's...

[Chrisnick]

With an internally stock F23A1:





Power/Suspension/Chassis Mods currently(basically I/H/E/TB, 4.266FD, stock ECU):
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
05-06 Acura RSX Type-S exhaust tip
F23A1 Swap
CE1 Wagon P2A5 4.266FD transmission
OBD2A P0H manual ECU
F23 intake manifold, TB port-matched upper
Bisimoto intake manifold gasket
62mm H23A VTEC throttle body
thermal TB gasket
IAT sensor moved to intake piping
Bilstein HD Shocks
Skunk2 Sport Springs
Progress 22mm rear sway bar
NO front sway bar
Neuspeed upper shock tower brace
Prothane Rear engine mount insert
Energy Suspension Front engine mount insert
Energy Suspension front radius rod bushings
Skunk2 5-speed dark grey shift knob
4th gen Prelude shifter
16x7 +45 TSW Trackstar 4's plasti-dipped flat black
205/50/16 BFGoodrich G-Force Sport Comp-2's

F23A1's suck and totally aren't worth swapping. Soooo close to running 14's. Car just doesn't 60ft like I want to, still gets a little wheel hop. Mounts and traction bar will be happening this winter. When I'd preload with the handbrake, it'd dig out GOOD then just spin the clutch into second. Ran 15.06 about 3 times, a 15.07, 15.09, then the last decent pass was a 15.12, all with 2.1-2.2 second short times. Hits the limiter in 3rd JUST as I cross the finish. Dropped tire pressures down to 20lbs, removed spare tire and passenger seat, which didn't make much of a difference at all since together they're MAYBE 40lbs. WOT shifting, of course. Dropping clutch anywhere from 4000-5000RPM, any kind of slip of the clutch would make it slip between shifts. Higher would spin, lower would bog.

Changes since running a 15.8 @ 86mph: H23A VTEC TB+matched upper intake, Velocity stack, cat delete+2.25" exhaust, and put a second IAT in the intake tube about 8" before the throttle body. 60ft times didn't really improve so I don't think the rear mount insert and radius rod bushings really did anything to help traction, maybe slightly less wheelhop at the track. Removing the cat and doing the full 2.25" exhaust helped the most, for sure, but the whole combo together makes it awesome. I'm basically at the limit of power with this gearing.

Plans for winter now:

T2T4 transmission
Stronger clutch
Ported/Gutted Lower intake
Traction bar
Solid mounts
Possibly a cam(since I now had a spare F23A1 cam)
Tune it.


Stay tuned kids, I'm coming for the cammed F22A's.

[Raf99]

No slicks?

[Chrisnick]

Nope, just dialed in air pressures on what I drive on daily. It would really benefit from them, as well as a limited slip, traction bar, solid mounts, double adjustable shocks.... you see where that's going lol

[af_1132]

Congratulations on those low 15 second passes, and the 90mph trap speed. I'm beginning to believe that I have an A6 cam as well, so you're not coming for me, hehe.

[Chrisnick]

I think your header and intake manifold are your limiting factors, moreso intake than header.

I about crapped myself at the times, I was NOT expecting it to improve .8 seconds and gain 4mph from the TB, V-stack, and exhaust.

[gloryaccordy]

Have you thought about swapping the F22A head? Yea you lose VTEC but they flow better and have better IM and cam choices.

['93CB7Ex]

or swap in a h22 and run mid 14's lol?

[Chrisnick]

Have you thought about swapping the F22A head? Yea you lose VTEC but they flow better and have better IM and cam choices.

IM is debatable, I can gut the lower of the F23 IM, have a LARGE but still smaller plenum than a similarly gutted H plenum(which is actually better from an N/A response standpoint, to a certain degree), with similar length runners. IM is not a restriction once it's modified. If I want or need a larger plenum, I'll just make a spacer between the upper and lower or make my own upper.

Geometry is better with the F22A head, sure, but larger ports do not necessarily mean higher flow; you'd be very surprised at the port size and geometry of some race engines, they're smaller and shaped much differently than you would think. The SOHC VTEC heads actually flow better from a flow bench standpoint as cast, and have a higher velocity. I'll take velocity over volume on a street engine that's not boosted. The POTENTIAL for both larger ports and velocity is certainly there from the F22A head, but I'm not really at a disadvantage at all considering the results from nearly all but the most hardcore SOHC builds. The largest downfall of the VTEC head is that there isn't too much of an easy aftermarket cam selection. If I do intend to do a headswap to eliminate VTEC, I'll go straight to the F23 Non-VTEC's head; simpler valvetrain(with the potential to run the VTEC's roller rockers), a camshaft that has normal lobes that can be reprofiled easily, and the SAME casting as the VTEC head. I don't really see the benefit of the F22A heads if I'm not doing any porting, other than possibly an easier way to put a camshaft in. Dollar wise, after that kind of investment, I'd probably be better off with a custom VTEC cam from DDTech, hardwelding and all. It's definitely less work.

or swap in a h22 and run mid 14's lol?

If I H-swapped, I'd be disappointed if it didn't go mid 13's to be honest. As it sits now, the difference in acceleration isn't THAT much. The gearing and powerband work out fairly well with this combo. Shorter gearing would help overall, but in the 1/4 mile, I'm not gaining too much by going into 4th gear since I'm hitting the limiter in 3rd two feet after the traps. The extra shift even has the potential to make the car run a SLOWER time than what is already has.


With what I have currently, and what's in waiting/going to happen, the car WILL be in the mid 14's very, very, very easily next year, without even touching anything inside the head/block. I love how downplayed the F23's are, keeps parts cheap and results more satisfying. As before, my plans for winter:-

T2T4 transmission
Stronger clutch
Ported/Gutted Lower intake
Traction bar
Solid mounts
Install cam gear
Tune it

A cam will certainly come later as long as I don't somehow manage to kill this thing. AFAccord and I have been talking, and just from the power mods(cam gear, intake manifold, tune) I should easily be able to see another 20 peak HP/TQ, with nothing lost throughout the rev range. Only once I make more power will there be better application with the intended drivetrain/chassis modifications. 180whp/tq is the goal with at least a 14.5 @ 94-95mph, 2.0 second 60ft on street tires, without touching anything internally... and still being my daily driver/autox beater.

[GhostAccord]

If you are staying NA. Nice duration cam with some overlap and a set of individual throttles will more than get you to where you want to be. Will it be driveable on the streets, Yes! If you take the time to tune it. As I'm sure you would.

[Chrisnick]

I'd bet even with the stock camshaft properly sized IRTB's would be a HUGE improvement all over the powerband.

You don't happen to have anything laying around that could give me a head start on such an undertaking, would you?

[GhostAccord]

Sorry, the two sets of throttles that I have are spoken for. 1 for my 2.1L Ford and the Ducati set for the F22 flange will some day be up and running. That being said, everything has it's price.