GAINS: Cams -vs- Pistons

Alright, its beginning to sound like the pistons may be more trouble than they are worth... so my question is, what is the difference in gains from, say, CTR Cams and CTR pistons? Or, Skunk2 Cams and CTR pistons? Or should I drop this whole internal idea and get a Skunk2 Intake Manifold? IDEAS PLEASE!

i wouldn't mind hearing the answer to all this as well.... Si2000, why do you say pistons are more trouble than they're worth?

why would getting the manifold mean youd have to forget the others? its only like 330 bucks

More importantly, what are your power goals for this engine, what is the intended use, how much will you have to spend total, and what mods have you done so far?

When it comes to building a motor up with aftermarket parts, you HAVE to have a plan before you start buying things. What's your plan?

Originally posted by texan
When it comes to building a motor up with aftermarket parts, you HAVE to have a plan before you start buying things. What's your plan?
This is absolutely true, and seems to be heavily lacking around here - all the parts must be designed to work together to produce good power. For instance, cams, pistons (compression ratio), and head porting must all be chosen to produce the maximum efficiency - if one component isn't set right, the whole assembly suffers. Even if you have top quality components, if they are not matched well to each other you will produce poor power, poor mileage, and have loads of reliabilty problems.

That being said, if you are only going to make ONE internal engine modification in your entire life: A set of mild performance cams is usually the way to go.
:cool:

Originally posted by fritz_269

A set of mild performance cams is usually the way to go.
:cool:


And in your case Si2000 Vtec that is the best advice to take.

Get a good reliable shop to install them with some Adjustable cam gears, and get them properly tuned on a Dyno.
Forget about a new inlet manifold etc, but a CTR type 4-1 Extractor might help a little (for some reason the USDM B16a has a poor exhaust manifold design compared to JDM version)
You should feel a noticable gain, and a peak hp increase from 160 to around 175hp.

what kind of gains could be expected from a b18b with street cams, adjustable cam gears, CAI/h/e, type r pistons, ss valves, bronze valve guides?

Originally posted by soul180
what kind of gains could be expected from a b18b with street cams, adjustable cam gears, CAI/h/e, type r pistons, ss valves, bronze valve guides?

I assume you mean a B18c? in which case you would basicly be building an almost Type-R engine, and so would have almost as much hp. (depending on your choice of "street" cam of course, you might get more)

If you are talking about a B18b, then gains around 15% could be expected, but then it depends largely on the type or cams you choose, and what the fuel delivery and ingnition limits are on the B18b ECU.

You might find for the money it would be cheaper to simply swap the B18b for a VTEC B18c.

i am tlaking aobut the b18b ls engine. Around my part of town, it definietly is not cheaper to do the swap. I am thinking of crower cams, as well i am going to get a str high flow fuel rail, aem fuel pressure regulator, probably stock injectors, unless they are inadequate. Thanks moppie!

sorry, also, i'm planning on getting 8mm spark wires, ngk (or the like) plugs. I hear it will be well worth it to upgrade to a msd ignition and modified distributor cap.

soul180 - AFAIK, There is no need for the ss valves, bronze valve guides, fuel rail, or 8mm wires or an ignition. You probably won't need an aftermarket FPR either. None of these things will give you more power, because none are inadequate in their stock form for a mild-cammed NA B18b with a stock redline.

Save the money - particularly on pulling the head and replacing the valves and guides for no reason.

Also, you might want to keep asking around to make sure you can run the type-R pistons on the pump gas available in your area. What will they make your static compression ratio?
:cool:

one thing i should add is that i plan on doing a mild port and polish job on the head, does that make a difference?

Wow didn't think people were going to reply! They never do...

Anyway, current mods are: AEM CAI, DC 4-1 Header, Tenzo Axle-Back.

Plans: I'm going to buy the pistons. A friend of mine that is building an LSvtec is going to help me put them in. Eventually, I want to rebuild the valvetrain and get a new ECU to benefit from the higher revs.

The money I am dealing with right now: About $800. I'm picking up the pistons and rings new for $330. That leaves me with about $300 to play with after all my machine work is done for installing the pistons (shaving the rods, honing the cylinder walls). I was thinking maybe Skunk2 Intake manifold? Maybe an SAFC (don't see a need for VAFC)?

So what do you guys think?

are there different rods you could buy so you woulnd't have to shave them? also, what's honing the cylinder walls?

honing the cylindrs is that thing you put on the dril and it has like lots and lots of little balls trhat push against the cylinder wall and it spins and ypu go in and out, thats what leaves that 30 degre checkerbopard pattern in the cylinder walls. I have one bnut moine just has 3 long friction pads.


You can probably get a better explanation from someone else, but oi tried! :D

Sol180 have you ever thought about putting a b16A head on your B18B it would give you a lot of juice up high. Sorry I'm off topic just thought I ask

What 94tegRS was describing is called flex honing, which is not a true cylinder honing in terms of really taking off any amount of material (nor does it align hone the bore with a torque plate). Honing is the process by which one opens up the bore through precision machine work to either just clean it up or to increase the bore size for more engine displacement. Unfortunately, on most aluminum block motors (which have thin cylinder liners of various materials) there's very little material that can be taken off before you have to replace the sleeve entirely, which is a whole 'nother topic along with more machine work.

so what is the thing i described good for? when I rebuilt my bug engine, my dad had me do that to it, and I know they looked alot better inside at least.

Oh they work, don't get me wrong. But they only take off about .005" maximum I believe, which is good for a basic cleanup assuming there's no real scoring of the bores. If there is, you can't remove enough material with them and still keep the bores straight. So they work for a simple rebuild when there's nothing wrong with the cylinder bores other than normal wear, but if they are scored or out of round in any way you'll need real honing machine work.

so is there a need to do this if i replace my pistons, or is it just a good idea while it's all torn apart?

Yes, you always clean up the bore when you replace pistons. The new rings need a proper surface to seat to. Cylinder sealing is fundamental to engine function and performance, it should be given the highest priority during any engine rebuild.

Hey Texan, while you're on the subject what do you think is typical for how much over-boring you can do on a Honda motor before you have to re-sleeve it? Just curious. :)

I believe the ballpark is around .020" for most Honda motors, but I could be mistaken. And that damn metric conversion thing always confuses my memory :). The gist is that overboring to make meaningful increases in displacement basically isn't possible with stock sleeves, you have to do the expensive machining work to get anywhere with that approach.

Makes sense. The most you can safely go on the Cobra aluminum block bore is about .030". Enough to be able to play with the valves a bit, but not enough to increase displacement all that significantly. Cool. :)

BTW, what do you think of Ford casting the Cobra block in iron for the upcoming '03 year? Seems like a backwards step to me, evidently Ford doesn't have aluminum blocks quite figured out yet.