Doing a little building of my motor...(caution-nerd stuff inside)

AltimaXX said:
Bone-Dynamic compression doesn't refer to variable compression, rather it refers to the actual compression ratio when the engine is running(I believe that's how to put it) Ordinarily, the compression ratios that people refer to are "static" compression ratios, but larger, more aggressive cams will actually bleed off compression(as will timing that's incorrect, for example if an aftermarket cam isn't degreed correctly) so that's where you get the "dynamic" compression ratio. You have to be careful not to give up too much of your compression via the cams...which is one of the reasons why you want a higher compression ratio when you use more aggressive cams.
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This is why Mazda has multiple listings for the compression ratio of the miller cycle engine it's millenia S, it purpously runs long duration intake cams that push air back out the cylinder... or more correctly compress against the supercharger.

thedguy-:lol: Believe me, I'm fighting an uphill battle with very short legs and carrying a lot of weight. I wonder myself why I bought a Honda when I'm worried about midrange and low-end power...but oh well. I love the whole package of the car...it's exactly what I want. Plus...I kinda like being different...uphill or not.:)
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I was only kidding ;) It'll be interesting to see a Honda engine that doesn't have to scream out to be useful.

I hope to have the funds in the next year to build a motor for the miata, it's starting to lose oil pressure, and it's burning oil.
 
Update time...and depressingly, they aren't what I had originally planned. However, the motor has moved forward...

The motor's timing had been set incorrectly, and fixing that made the car run better all around. (not by me, ironically it was the only time the car has been touched by a professional mechanic since I've owned it...that's what I get for trusting someone else with my car, I suppose)

I had a good opportunity to switch to a higher-quality header that a friend of mine had, so I jumped on that and am very, very pleased with the result. The new header, while still a 4-2-1 design with a 2" collector, has much larger primaries and better transitions and welds. The motor's power now carries better out to redline...I hadn't realized how much my old header was choking the car down.

I fried the stock clutch at the track, and swapped in a SPEC 6-puck sprung hub clutch, combined with a Fidanza 8 lb flywheel(down from 18). I love the flywheel, and the clutch grabs like a grandmother from hell, but it chattered fairly badly until I also upgraded to solid billet motor mounts.

I also got a good deal on a transmission from a GSR model Integra (Sir-G, or Si-VTEC, for those of you outside the US) and have that waiting to go in when I get a chance.

I've also dropped another 10 lbs off of the car with a lightweight battery...still have full front interior and working A/C and accessories.

Unfortunately...all of that has cost me a fair bit of money, and I also have had to redo my rear brakes twice due to 1 incorrect install(my fault, I admit) and one defective part, so that set me back as well. I still haven't even been able to get my cams in yet...but all in due time. I'm actually very happy with the motor as it is, so I'm probably going to put off the motor another paycheck or two, or even wait til after christmas, and go ahead and upgrade my tires and dampers. The tires that I currently have installed have too large of a sidewall, so switching to stock or slightly smaller sidewall tires will help drastically with the car's gearing, rotational inertia, and handling. I also need to find time to pull off my crank pulley, and take it to a machine shop...I'm going to have the extra groove left over from the power steering belt machined off, which should save roughly a pound.

I apologize for the slow update, and strange change in plans, but such is life. I'm not one to pass up deals when they come up, even if it means pushing back other plans.
 
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What plans do you have for tuning once you get the engine upgrades? This will help get all the horsepower from the upgrades you plan on doing. Crome or Hondata are popular routes, and if you decide to modify the engine any further you will need tuning anyways. Not to mention the security of knowing you aren't running too lean.

What header did you end up with? Did you notice any more rattles or squeaks or anything when you switched to the billet mounts? Mine are getting pretty worn and I am considering upgrading to billet or just going OEM.

Also, I have a set of Tanabe Sustec coilovers I took off my DC2 this summer if you are interested. (Switched to Koni Yellows and ITR Springs)
 
I'll be doing an OBD1 conversion with a chipped ECU tuned on Crome by a local guy who's very, very good. I ended up with a Greddy header, and I absolutely love it.
The billet mounts are, to be honest, horrific. The car vibrates so badly that not only can I tell I have solid mounts, all the time, but everyone else can, too-the car sounds like a tin can full of gravel siting at idle. It's bad...I'm going to change them out after christmas.
 
sounds like fun! just wondering... what kind of suspension mods are you planning on having done to your car?
 
I've got Tokico Illumina shocks, a 22mm rear swaybar(OEM Integra Type-R), adjustable spherical swaybar endlinks, poly bushings here and there on the suspension, coilover sleeves that I'd like to replace with springs, my car came from the factory with the upgraded 24mm front swaybar, lots of chassis bracing, hawk brake pads and powerslot rotors. It's a riot in the mountains :D
 
I've heard good and bad things about the billet mounts (and poly bushings too).
You could always fill a stock motor mount with poly window sealant to add some stiffness.
This is an alternative some people use before switching to billet mounts.
My brother said the ITR rear swaybar was one of the best mods he did to his Integra in terms of handling.
I am hoping to do that this summer with a rear subframe brace. Did you notice much of an improvement in handling from switching sway bars?
 
Hard to say, honestly. The swaybar helped, I think...but I'm really, really picky about the way cars handle, and mine drives me crazy right now. It just doesn't feel composed...I honestly liked it better with the stock bar, I think. I have pretty stiff springs, so the car isn't that bad even with no rear swaybar...it understeers when pushed, but it feels good aside from that. I've had filled mounts, and inserts...even those didn't even begin to hold this clutch lol...ah well.
 
Just a little update...after far too many delays and much time with parts sitting around and no time to install them...I dropped my car off at a friend's shop for the cams and valvetrain to be installed today. I'll try to update with videos and pictures by this weekend.
So damn excited :D
 
jayhawk said:
Same here. To turbo it, in my opinion, is an insult to the engineers who designed it for anything but forced induction.
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I think I've brought it up before, but a great NA engine like that also makes a great boosted motor when rebuilt for it.
 
True...Honda motors make great power boosted. It's just not my thing, though. I am riding in a 350whp Integra tonight that's threatening to change my mind, though.
News...the car feels amazing with the cams. It pulls hard to the 7600 rpm rev limit...I love them. Videos when I can get my point and shoot back from my mom...
 
Does that new gearbox have a helical diff in it? That thing transforms the car, the torque biasing makes the car feel impossibly grippy when you crank the gas out of a corner! :D
 
Any updates?
 
Ahh...not really. Car still sits as it did last time I posted. It's for sale now...I'm trying to find an NA Miata. The car feels great, it pulls hard for what it is. I never got any videos of it, I have no way of recording them...so...
 
My friend just got a DC4 LS and I've been trying to convince him to go NA B18B like yours because its just cooler. Seems like they can make just as much power (or close to it) with more torque and a more usable powerband.
 
Well, they won't make as much power past a certain point. 160-170whp is the most you frequently hear about...people have broken 200whp with fully built non VTEC motors, but a bolt-on Type-R swap will make that...soo... My car is making about the same power as a stock LS/VTEC hybrid motor, but mine won't make much more power and still be very streetable. A VTEC motor can be massively cammed, with 12:1 compression, etc. and still be just as streetable as my mild non-vtec build.
 
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AltimaXX said:
Yeah, I'll need to be very careful with the timing. Milling the head will throw the timing off as well. The cams I'm buying are high quality, so I'm not too worried about them being off, but I'll be careful...thanks for the advice.
Haha, and yes, I am rather unique in that regard
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Are you guys saying that by milling the heads down, the cam is closer the crank, (isnt the crank pulley that what your timing belts run off of?) so the timing belts are off?

Or is it just that these smaller motors are a lot more affected by advancing or retarding the cam in relation to the bottom end?
 
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InfernalVortex said:
Are you guys saying that by milling the heads down, the cam is closer the crank, (isnt the crank pulley that what your timing belts run off of?) so the timing belts are off?

Or is it just that these smaller motors are a lot more affected by advancing or retarding the cam in relation to the bottom end?
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Milling the head changes the distance between the pulleys and tends to have an effect on belt length.

On my miata's engine if I mill it the head .020 I can gain nearly 4hp, most of that is because the timing gets changed by a few degrees.
 
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