I wanted to keep this setup under wraps until it was done but I thought if I got all the H-T members imput it might come out better. Anyways the goal here is to gain low end hp/torque on a 2000 Integra GSR under current Street Prepared rules.

Plans:

ITR Throttle Body:
Overbore (70-68mm?)
Knife edge butterfly plate
Replace screws with rivits or countersunk screws

GSR Manifold:
Knife edge butterfly plates
Replace screws with rivits or countersunk screws
Port match with overbore throtle body

P72 OBD2 2000 ECU:
OBD2=>OBD1 reprogram
Agressive fuel maps


I'm not considering the ITR manifold because you sacrafice low end power. ITBs are out of my price range. Tech3 is an option but not worth the $ in my opinion (right now that is). By using the P72 OBD2 ECU I can directly plug in the ECU w/o a harness adapter and when I drive on the street or need to pass smog I can switch back to my un-modded ECU.

Please post if you have anything that I should add to this list, preferably mods to the TB, IM or ECU.

I will be posting dyno graphs from before and after these mods (whenever I finish them).

 

hey...I think I talked to you at nationals! I was the tall white guy with the shaved head asking you about your wheel offset...yada yada....anyways, that set-up sounds good. have you considered balancing your engine? punching it the allowable .020 over? shaving the head the allowable .010? run a lighter flywheel? I dunno...that's some of the things I'm planning but I'm running an Integra RS in DSP so I need to find all the HP I can if I want to keep up with the Bimmers

 

Legally in SP you can go .0472 over on the block. You can mill the GSR head .2mm based on a height of 142mm (i.e., minimum heade height of 140mm).

Carlos, you should push to have the classifications re-written to put all G3s except the ITR on the same line in DSP. This would allow you to use a GSR motor and would allow me to fill my sunroof and get a new headliner I plan on having the engine rebuilt this year at .040 over and port matching the head. I'd like to do some balancing too if I have the cash. I'm really in need of power; the car handles about as good as its going to.

Incidentally, if you haven't written your letter to the SEB asking for the upper a-arm replacements, please do. I have too much negative camber right now, to the point where I am not using my entire contact patch... I'm sure more tire contact would help me go faster.

Mike

 

dunno which setup, but power isn't everything.. depending on the track, that is..

 

Agreed, but the south course at this year's nationals really benefitted the cars with more torque. Having a second driver and rear wheel drive helped too...

Mike

 

agreed....south course power+lightweight=fast in the class I ran (EP RX7) you HAD to have a 2nd driver if you wanted to win....look at Jon Thomas and how many years him and Tom Lombardo have been co-driving that little civic in EP!

 

you run in the DC area?(fed-ex field/rosecroft) i think i've seen your car a lot.. black GSR with panasports?

true. some tracks are most definately built for higher horsepower cars.. which sucks for me because i'm in SM2, where as long as it's 3.0 liters or under, anything goes for power-wize!!! so i'm gonna turbo, super-charge, and spray a 150 shot on my B16a crx. heheheeeee. j/k...

it would be nice to see some dyno numbers of the setups you're thinking about though, it would make it easier i'm sure..

 

Hmm, one minute you're trying to convince me to switch to DSP and the next you're talking about mods. I smell something fishy here!

I didn't stick around but how did you do on Sunday's enduro?

 

Yup, that's Mike.

And the courses at Nationals tend to be like FedEx (large and fast).

Back to the original question - I know in Improved Touring, much of the power gains to be had comes from blueprinting the head and valvetrain. The head rules are very similar to SP (stock, shaved a little, port matched). If you have a few extra dollars lying around, this might be a good place to look for power.

 

all G3s except the ITR on the same line in DSP

Right. The ITR should be on its own line in DSP

 

hahaha...man I have a friend who runs a DS ITR, and just for kicks he decided to run CSP with it....gave all those miata's a nice whoopin'!

 

I know this quite well. My suspension is working great (I just need to drive better) and I could always use some more low end power. The TB, IM and ECU are only costing me $350 for all three then there is the cost of the modificatons so it's not like I'm blowing a large sum on money on this project.

Before my post gets completely hijacked , have any of you had any luck with (or tried) mods as mentioned above. I'm not looking at any engine work right now as I need the car to drive every day and the above listed parts I can put together and install with no down time.




[Modified by Geratol, 12:14 AM 10/8/2002]

 

As you know my tires are on their last few runs. I go out and start doing the laps, 1, 2, 3, 4, no white flag, 5, there's the white flag, 6, checkered flag. I come in with a 3:00:xxx on 6 laps. Of course I get a re-run which normaly is great but my tires are so near cording. I water them down and bleed some air and do five more laps with a 2:32:xxx. Enough for first place in my one person class but I was happy with the overall time even tough my first set was faster. When I went to change wheels my rotors were bright blue/purple but the brake pads never once faded .

 

have you maybe thought of getting a larger throttle body and knife edging the butterfly and what not? that'll give you better tip in. All the cars I've driven with larger throttle bodies have INSTANT throttle response.

 

Another thing you could try is installing something like a phenolic spacer between the head and the manifold. It has two benefits: 1 - keeps the manifold cooler by isolating it from the engine. 2 - Effectively lenghtens the intake runners (depending on thickness) and increase low end torque... How much room between the firewall and the manifold on a GSR anyway? A 1/2 spacer should fit, nah?

Another thing to do maybe, would be to extrude-hone the manifold...

 

I had thought of the Hondata intake manifold gasket but I couldn't tell if it actually helps or is it just the flava-of-da-month. I'll also look into this spacer you mention and how much room I have to work with.

As for the extrude-hone, I'm not going to do anything like that because I have heard that the inside of the manifold needs to be rough to promote air/fuel mixture.

Thanks for the sugestions, this kind of post is what I was looking for when I started this thread.

 

Ahhh... your secrets out. I was acutally going through some similar ideas my self... I was thinking about the rebuild that mike mentioned. After discussing some ideas with a friend locally I'm very wary of loosing what little torque I have. You said ITBs are out of your price range but do they acutally produce noticable lowend grunt?

oh... I've also got that e-mail for you....

 

That's an old myth leftover from the carburator days... Not an issue on a modern FI intake manifold since the fuel gets injected at the exit of the manifold and almost directly into the head. For the head intake port however, the rule still applies, but you can't port more than 1 inch into the head anyway...

 

Thanks for clearing that up. Now if I increase diameter of the runners then I have to increase the size of the ports in the by-pass bracket (or whatever you call the gsr secondaries thingy) which would call for new larger brass butterfly plates and more custom work.

I still wonder, why would honda still make intake manifolds with rough interiors if it isn't necessary?

 

DONT TEMPT ME!

 

As usual, the answer is COST. Sand cast-aluminum parts are dirt cheap to make...

 

I'm not trying to tempt you... I'm just trying to get some useful info on an ITB setup. So I can tempt myself... Seriously though, Do ITBs suffer the same problem of loss of low/midrange power that you'd experience with a Type R manifold or Skunk 2 manifold? Anyone have any practicle info on this? Any info? impracticle info..?...? I know you're out there...

 

In a nutshell, ITB setup use VERY short intake runners compared even to ITR manifold. Longer runners produce better lowend torque than short runners due to increased velocity...

IMO, it is futile to try to make any significant low-end torque gains with these engines. You are better off concentrating on top end power and adjusting your driving accordingly. I mean it's probably easier to gain peak 20hp on top and extend your useable RPM range by 1000rpm than to try to make some measly 5-6ft-lbs at 4000-5000rpm. And the extra RPM on top will give you several MPH in each gear and would be more beneficial on your average solo2 course...

 

I was under the impression you couldn't safely raise the the RPM range with these engines without upgrading some internals... llike valve springs etc... Keep in mind I'm no Mechanic (I just break things), I just drive the damn thing

Edit : Especially raise it 1000 RPM... seems bad to me....


[Modified by Watkinsm3, 8:41 AM 10/9/2002]

 

Sure you can. Sure it won't last 300K miles anymore but I mean it's not like the engine will blow up the first time you run it to 8.5-9K. Besides in a typical autox, it will only see a few short bursts in 1st-2nd gear to that RPM. I would worry more on a road course where you run 20-30min sessions at those RPMs in 4th and 5th gears... If your engine has more than 60-80k miles on it, just get some new springs and you'll be ok...

And hey, besides, if you wanna make a run at the big-boys in DSP in Topeka, sooner or later you will have to consider engines "wear items",