17 replies to this topic

[cbstdscott]

... let me ask you this, would you opt to build a stock EW4, over swapping in a D16a1, and if you do say build the EW4, then would that "built EW4" produce as much power, or more than a stock D16a1? Say in the range of 113 HP.

Cliffs at the end-

Let me ask you a question: How do you plan on using this engine? Is it race only? What type of racing? Street only? Street with occassional track use? What kind of occasional track use? Drag? AutoX? Road Course? Circle Course?

I will guess that this is for your street car and that you want some more "performance." It seems that the larger displacement, DOHC D16A1 would be the "better" engine. The DOHC design is going to deliever more peak HP. So if you were running at or near redline all of the time, the DOHC design will yield more power. But a car that is driven on the street needs low end torque to get away from stop lights, etc. The three valve design (recently adopted by Ford and Mercedes) of the D15A3 generates relatively more low end torque per cubic inch that the bretter breathing DOHC design.

Modern cars use some sort of variable valve timing to give low end torque and high end HP. When Vtec "kicks in" it is the valve timing changing profiles. Our old engines are "stuck" with a single "personality" dictated by the cam profile and hed design.

The other considerations are parts availability and weight. The EW/D15A3 engine transmission combination is slightly lighter than the D16A1. Not a huge difference, but on a light car like the CRX, every once makes a difference. OEM parts are still available for both engines, but the aftermarket largely ignores both engines so you will need to scrounge parts. If you want easily available "bolt on" parts, consider a B or K series swap.

My engine decision was made for me. I stumbled over a New-In-The-Box Mugen LSD for the EW tranny and so it was easy to stick with the stock USDM engine. AFAIK, the D16A1 has a Quaife unit available for it. So all things being equal, I would go for the engine tranny combination that has a readily available LSD option if you are serious about performance. Because power is worthless unless you can put it to the road.

The path to more power is the essesntially the same for all engines: Better breathing, i.e. Improved flow through the head.
Machine shop work combined with more aggressive cam profiles and more total induction (larger throttle body/multiple TBs or multiple carbs) will creat a lot more power. Changing to a more sophisticated ignition management systems like OBD1 will also find some more performance, but it is cheap and simple to just swap in some lighter advance springs into the distributor for similar results.

I hate to quote dyno numbers because they are only useful for comparing before and after results of tweaks made to an engine when measured on the same dyno with the same atmospheric conditions. But my EW has been measured at 99whp (~120hp at the crank) and it passes California emissions testing using the techniques I have outlined.

Cliffs- You can not go wrong with either engine, but recognize that you will need to use your imagination and some engineering skills to tweak them for power. Do not expect to order some easy bolt ons from Summit and get your target HP number. You will need to pull the head and have it worked over. And you will need to fabricate some way of hanging a larger TB on either engine.

Scott

[rinnaye]

Scott,

In a nutshell, I can sum up my engine upgrade intentions around having a reliable, yet potent daily driver that will pass emissions. Since the BAR's referee program has been at least temporarily dismantled, I guess the D16 swap is not looking too good for now.

Thanks for your input, and I look forward to hearing more of your expertise at your upcoming annual Weenie Roast.

Rene

[Jill]

Jill: If you do go NA I could get rid of that turbo set-up for you. If the other "guy" had it set up for turbo, then you would have to Un set it up for NA. I say use it if you got it! You could get T3 gasket kit cheap. That would stop the leaking. You need to find out what the "guy" did to the fuel system...EVERYTHING. How much boost are you planning? If you stay in the 5-6psi range, upgrades will be a lot cheaper. Go any higher and you open Pandora's Box! I've tuned turbo DSM's before I got my 1G, so I know a little bit about this. Applying turbo to 1g's, I dont know much.

Like I said.... IMHO I would run the turbo till it blows up (if it does) then rebuild it to be "the SuperTurbo Beast"!



<-----where is "somewhere" If you don't mind. I know/knew a lot of turbo "guys" in Colorado Springs.

I do have another garrett t3 turbo that I got with the car I'm planning on running 5 psi of boost. What do I need to find out about the fuel system? I'm hoping to drop the engine this weekend so I can get half of my garage back. We'll see, the wiring harness inside and out has been a royal pain! Oh well, I have one car about 75% done with the removal of the harness, I'm not looking forward to the removal from the other car. But, what had to be done, has to be done! Suggestions on a good exhaust setup for the turbo?? It's all setup right now, but, the exhaust is running to the side of the car-drivers door-some custom crap. I'd like it to be loud, but, need to get the right setup with a catback on it as well. Actually, I live here in the Springs. If you know of anyone that you would recommend, let me know!