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Looking at competing in NASA honda challenge. For those of you that don't know, its a road racing series with NASA with very particular rules. I've decided that the best route is probably to go with the lightest package possible since all cars are run on the same size tires, which means i'll be using a CRX! With that in mind, i can use basically any engine, but there are some serious weight penalties for using B and K series stuff.

I've decided that a D series will be the best route forward. It'll allow me to hit minimum weight easier than any other engine due to a D series being a solid 100 lbs lighter than a B series, and probably 150-200 lbs lighter than a K series. Not only that, due to the restricted engine mods, i'm not convinced that a B or K series can make enough power to offset the additional weight. Keep in mind all cars will have full roll cages for wheel to wheel racing (added weight) and cutting of the unibody is restricted, so you can't go balls out tube-frame to cut weight. Take a look below to see how far you can build each engine.


1) OEM throttle body (from any series engine)
2) Non OEM cams will incur a minimum 100 lb penalty
3) Cams, cam gears, valve springs, retainers, and keepers are unrestricted.
4) OEM rods required (from any series engine)
5) Valve preparation (angle, cut, etc.) is unrestricted
6) Engine management systems are unrestricted
7) Cylinder head preparation and porting is unrestricted. Valve size and material must conform to original specification for that particular head.
8) Intake manifolds must be unmodified OEM Honda parts.
9) Port matching is allowed but cannot be machined beyond one (1) inch into the intake manifold


Couple restrictions based on engine class
1) Max Compression: D series - 12.7, B series - 12.7, K series - 12.5
2) Min Vehicle Weight: D series - 2000, B series - 2250, K20 - 2350, K24 - 2600
3) K series must use OEM cams, Max compression of 12.5
4) B series must use Unmodified OEM crank, max 70mm throttle body, OEM style “log” intake manifold, engine otherwise unrestricted (unless otherwise noted above)
5) D series completely unrestricted (unless otherwise noted above)

That's it!

So right off the bat, the k24 is out due to a maximum of 250lb of ballast being allowed. Can't get up to 2600 lbs.

So i'll summarize each engine...

D Series - 100 lb penalty for aftermarket cams (is it worth it? Probably not?) Max Compression 12.7. Unlimited head prep. OEM intake manifold. Can you mix/match enough OEM cams (JDM d15b?), with unlimited head prep to match a b series in power output?

B Series - 250 lb penalty over a D series. 70mm max throttle body. 12.7 Max Compression. OEM intake manifolds. Unlimited head prep. Is aftermarket cams worth 100 lbs over a b20 vtec with CTR or ITR cams?? I think probably not. Is a b20 vtec with CTR cams worth a 250 lb penalty over a D series built to limits above? How much more power can a B series make over a D series within this ruleset?



K20 - Stock cams, OEM intake manifold, max comp of 12.5. Unlimited head prep. How much more power can this make over a D or B series engine build within the same rules. Is it worth a 350 lb penalty over a D series? 100 lb penalty over a B series?? Maybe a type R setup??


I'm not sure if its possible, but if you can hit 160 wheel on a D series in this build, it might be better than the B or K series???
 

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Discussion Starter #2
Just throwing this out there, but can K or B series intake manifolds fit on a D? did the D series integras have aggressively tuned intake manifolds?
 

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Brokedick Millionaire
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Skunk2 intake on a D16A6, LS TB I think. Do the points/dyno to fit into H4. Seek out info from various posts from Myers Motorsports (Sam Myers) who won NASA (and SCCA)

I've forgotton how many wins I've gotten under Sam as his transmission builder, as well as SCCA ITA and STL wins with other teams.

I think the car with B16 swap does H2 duty and with an intake/TB swap falls into SCCA STL classing, aka 2016 National champion @ Indy with Adam Roberts wheeling the car.

"The Other Wife" doing splitter testing

 

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Discussion Starter #4
Skunk2 intake on a D16A6, LS TB I think. Do the points/dyno to fit into H4. Seek out info from various posts from Myers Motorsports (Sam Myers) who won NASA (and SCCA)

I've forgotton how many wins I've gotten under Sam as his transmission builder, as well as SCCA ITA and STL wins with other teams.

I think the car with B16 swap does H2 duty and with an intake/TB swap falls into SCCA STL classing, aka 2016 National champion @ Indy with Adam Roberts wheeling the car.

"The Other Wife" doing splitter testing

So your recommendation is to forget H1 and go for H4?? I thought skunk2 intake manifolds qualified as non-oem?
 

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Is HC even still a thing?

I was thinking about building an engine for the Tape-R to run HC, but I've talked to several regional NASA racers and officials, and they've said the class is so small in the Central states that they may not continue to run it or group it with another class.
 

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Brokedick Millionaire
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NASA Championship will be at Mid Ohio again in 2019....wonder if Eric Waddell, Adam Roberts, or Greg Vanderslues will drive it?
 

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Tape-R taper/driver
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Sorry, I should have been more specific.

I don't know if the whole class is getting dissolved, as I've heard the coastal regions still have decent attendance. I was just dissuaded from prepping the Tape-R for a class that I either couldn't race in or would be running solo or with minimal competitors locally.
 

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Brokedick Millionaire
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D-Series Tech - High Compression Stroker - Honda Tuning Magazine

It’s an pretty old article, but they used a D17a7 rotating assembly in a d16 block. It made 171whp and 135tq.
It also kept having issues for Colin. Either popping head gaskets or pushing out oil pan gaskets. The only reason Colin won his class at NASA Nationals @ Mid Ohio was because I had a spare set of shifter forks at home that I brought to Mid-Ohio on Saturday night so he could race on Sunday. IIRC he only needed to make 1/2 the laps to get enough points to win.

Again, it was Sam Myers who called me while I was running my courier route asking if I had a set of forks. Due to the time issues of slapping the trans back in the car Saturday night and trying to get some sleep for Sunday, Colin didn't have time to stop by to say "Thanks".

But the next NASA event we both were at, at Mid Ohio, he hunted me down and brought beers to chat.
 

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Ill be honest, a d15 w its rev potential, open head porting and 12.7:1? I tell you thats what id be doing, a d15 that would rev out to like 9k even w the 100 hp (edit :lbs) penalty. Ppl rev em like that making no power to avoid a gear change now and again and they hold it fine. Piston speed is what it is.
 

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Brokedick Millionaire
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SS did a NASA build D16 "High Compression Stroker D16a6 Using D17a7 Internals" I cant post links
I didn't last long either.

I got to talk with Brian @ HASport about the engine builder, did some transmission work for the second owner/driver, Colin Botha.
 

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Do you know of anyone running a d15 in competition? The lucky dog rookie car runs a usdm b7 block w z6 head and has lasted 2+ seasons of endurance events with zero glitches. Just pure track time. Hundreds of hours. Beaten by novices lol.
 

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Brokedick Millionaire
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I know someone who was building a D15B VTEC CRX, but running Grid.Life got in the way :)

It has a trans I built....
 
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