We had a little dyno day today at Import Speciality Automotive in Tacoma WA. Since I don't have much to adjust on my car, I took the opportunity to see what type of HP differences I'd see with different disk combos in the Supertrapp.
My distributor decided to **** the bed on my third pull and I ended up with a torque reading of 130. This is obviously not correct and contrary to popular belief at the time, I didn't "hit the NAWS".

Pull #1. 4 disks in. 85.3 hp & 93.7 tq
Pull #2. 8 disks in. 93.1 hp & 97.7 tq
Pull #3. wide open 94.6 hp & 130.1 tq (false tq reading)

Richard showed up with a turbo hybrid that put down 266 hp. I'm not a big fan of the drag race scene, but his car (daily commuter) just ran a 12.5 @ 112mph a week ago. That kind of stuff is actually pretty impressive. I took a few pictures... http://members7.clubphoto.com/john51...84/guest.phtml


[Modified by johng, 5:16 PM 9/28/2002]

 

Excellent info John, thanks for posting

 

Decent numbers for a D15B7. How many miles and what kind of mods?

I was thinking about taking my 93 Dx hatch to H5 in Honda-challenge, so that's why I'm curious.

Oh, and back on the topic...Supertrapp on my Honda ATV, I noticed serious gains with the more disks added. It did not hurt my torque at all. Only thing it did was make it a little louder, but that isn't an issue with a race bike.


[Modified by Todd00, 11:19 PM 9/28/2002]

 

so the more discs you have is better? Wouldn't that have more backpressure? Which is loudest?

 

Todd,
Mods..... what mods. It's a stock D15 with 190,000 miles. I was pretty suprised to see it make 94 at the wheels also. Must be a "Wednesday motor". The only thing I've done is add a Injen cold air intake, new plugs, wires and the clutch/flywheel. That's it. Now it looks like I need a new distributor. I'm just trying to make it through the last few events of the season with it. I'll tear it down this winter.
A few guys offered to donate their spare distributors, so it looks I'll have that taken care of by PIR on the 12th. The dyno graph looks terrible by the way. The line starts off okay, but by 4500 rpm, it gets very rough.

Jeremy,
The more disks you have in, the more air gaps you have between the disks. This means a more "open" exhaust, not more restriction.

 

John,

Spend the $100 and get the distributor core from the honda dealer and replace the whole thing. If not, the D series motors love to eat distributor bearings and no telling when one will go bad.

Put a header on that car and watch HP jump to ~100. D series has such a crappy exhaust manifold.

Still though, 94 is pretty good for 190K miles. I think SCC dynoed their D15B7 (befoe they swapped it out) and got around the same results. Amazing how well the D series holds up.

 

do you have any guesses on what kinda power you would make with no muffler at all. like if you just completely unbolted it?

 

118 whp hp with simple mods, likely class rules won't allow them.

I miss my old DX motor. Been resting on engine stand for 3 years now.

 

Todd,
Didn't know there was a bearing in there to be concerned about. Does it come with the new distributor standard? Do you recommend replacing all the inner bits at the same time, or just swapping over all the old stuff? The new core from the dealer is $120. The cap & rotor are about $40 for the pair, and the new coil thingy and igniter are $120 per bit. Maybe I'll just do the new core, cap & rotor for now.

Mista Bone,
Love the tranny info you have and I continue to find uses for it. I think I'll email you for more tuning tips if you're willing to share.

John -- who's donor distributor deal already fell through.

 

John,

https://honda-tech.com/zerothread?id=214630

Go the route with the $120 core and the cap & rotor. Well worth it if it has never been done. You might try ordering the parts from A&H motor as they are cheaper than most dealers.

 

Hello Johng,

Here is a page that was written by some one on G2IC on rebuilding B series distributors. The original page was shut down and Charlie copied most of it, I have the original save on my home computer but not web accessible, if you need it let me know. You should be able to use most of the info to repair yours less expensive than purchasing a new housing just for the bearing.
http://www.angelfire.com/ca/DrOhm/di...torRepair.html



[Modified by DB1-R81, 12:06 PM 9/30/2002]

 

Where were you earlier (or where was I)? I already dropped $180 at Honda for the new parts, and just finished hacking everything back together. Thanks for the link though.

 

Hey Johng,

Sorry, just one of those race weekends where I don't get on the computer to often. Good to here you got the distributor back together, just repair the old one for a spare, Honda’s tend to eat distributors.