Dimi

Does anyone make some sort of aftermarket high flow intake manifolds, ported throttle bodies and/or higher duration cam(s) for the D15B7? I want to make the most out of my motor without swapping so I'm thinking trying to get the most bolt ons as possible. I know most of you are going to say swap but I think it'll be a decent performer if I do intake manifold, cam, ported TB, header, 2.25" piping, lightweight pulley, etc...any input will be appreciated, thanks.

Jeice

If you want to make power on the d15b7, go turbo or nitrous. I have all the bolt ons and I didnt get much out of it at all. It's a waste of money.

Now my 55 shot kicked my car in the ass.

I'm not going to tell you to swap, cause I didn't either. But consider this : The money you spend on an Intake or header could be going to a turbo setup.. But if you want to go nitrous, IM me on AIM

Jafro

Things could be worse, though. Imagine swapping an "upgrade" of an engine into your Honda, and the engine IS a D15B7. Then you would be me. It really isn't that bad of a performer, and I frequently wonder if I should buy pistons, rods, and turbo this mofo. A 1.5L probably isn't worth all of that. The turbo kit will cost you 3x what you can get a LS motor for.

Cams... I think Bullfrog makes one. I think camming out a SOHC is pointless because you can't adjust the exhaust valve timing.

Intake... Fab the part. Cut the flange off of your current manifold, and find someone that can heli-arc weld. Make a short runner intake out of it if you want top-end power, just be sure to maintain 1.5x your engine's displacement, or it will run like sh!t. Doing this will almost certainly knock out what little low-end that 16v 1.5L produces, but it will help it up high. If you want power down low, intake velocity is the key.

The throttle body on a D15B7 is already a 56mm throttle body. Sure, you could go bigger, but I'm not sure what benefit that would offer. Most V8 mustangs and even 2.0L imports have 52mm or smaller throttle bodies.

I was tempted to buy rods, ARP hardware, and build mine to 10.8:1 compression. Almost 2 points higher... which would have added quite a bit of power to such a small engine. But I was convinced not to do it because of the cost of parts/gas issue. If I want to go fast, I have another car to do it in. I don't want to mess up my ability to run cheap gas in my daily driver. I certainly don't want to have to use 93 octane in a N/A civic.

Nitrous should be okay on a healthy D15B7, just don't go to big on it because D series rods are teh suck.

Jeice

An LS motor complete is roughly 1k and you say it's 3k for a turbo kit? Well yeah, 3k if you buy a complete kit from a manufacturer, but it's a hell of alot cheaper if you piece it together yourself. The only real money you'd be spending on the kit would be the turbo manifold, and you could always just go with an HF manifold instead. You could easily piece together a kit and spend under a grand, and be just effective as one of the 3,000$ kits.

I say go home-made turbo..

SRT_Andy

Hell, I sell the Greddy 15G kits for less than most people and it will eat swapped cars on a SOHC.

mrdx

Use Skunk2 SOHC intake manifold, D16A6 (CRX Si) cam, and www.proflowdesign.com (personally used them) for the ported t/b. Great sources and good prices.

Jafro

This isn't about a turbo kit, though. He wants to beef a NA D15B7, and the stock rods in that motor won't take the abuse of a turbo. You'd have to build the bottom end in order to hold the boost over time, and it won't be as inexpensive as an LS swap which would yield better results.

It would cost me over $1500 to fab everything for the turbo kit... buy an intercooler, get ignition and fuel control right, and an exhaust that could handle a turbo. Then factor in a set of rods, pistons and ARP hardware, and you're easily getting into the $3k range.

This is why I decided against turbocharging or building for a high compression NA setup.... The one on the left is a Hyundai 1.6L (4g61) rod. The one on the right is a Honda 1.5L D15B7 rod. They're both forged rods. The construction process for these is almost identical except for one major factor. The Honda rod is made of about half the material. Look at that tiny wrist pin, the rod is half as thick in all dimensions. I wouldn't want to increase the cylinder pressures on a D15B7 much at all. It won't hold it.

With all things considered of what it would cost to add a significant amount of power to a D15B7, an LS motor is a much better alternative (I found 2 locally for $450, one has a tranny). But if you want to be different and build a D15B7, start on the bottom end. Go nuts... nobody will have a car like yours. You'll be a pioneer. Don't think I haven't thought about it.

Jafro

Here's another shot...

Jafro

It's really an unfair comparison... I don't mean to do the apples to oranges thing, if you're raising compression on a NA setup, you run into almost the same issues with cylinder pressures that you would with a turbo. So that's why I'm illustrating this.

The Hyundai does amazingly well with a turbo on a stock bottom end. Maybe someone out there knows of a stock Honda rod that will fit the D15B7 that's beefier than they came with from the factory. It would be a lot cheaper than buying the Eagle set that's available. I know LS rods fit a 1.6L, I'm not sure about the 1.5L's, though.

Aside from a sheetmetal intake manifold, bolt-ons, and maybe a cam, there's not a whole lot you can do to the D15B7. There's not much room for head work, and if you do, it will offer little results at a very high cost. A 50-shot is the best bet (and 1/10th the installation trouble). That should put you around the output of a fresh LS motor with bolt-ons, but you'll have to refill it every 100 seconds.

Jafro

A pre-VTEC (88-91) Si cam fits a DX head. The cam timing is a half-tooth off, but can be fixed with an adjustable cam gear. You can install it either advanced or retarded, but you will need to index it to determine it's orientation when you put it in.