D15B 3 stage vtec in a CRX???

[re-evaluating]

Does anyone have any experience running a D15B 3 stage vtec? I have done a lot of reading and it seems to be an interesting option. I understand it has some drawbacks with engine management but I will be using a FAST system so not worried about finding rare ECU.

My FAST system is sequential with individual cylinder control and I can use nitrous outputs to control the vtec. I believe I can get the AF into lean burn where needed.

If anyone has anyone has any experience with the motor I would be interested to hear the pros and cons.

If anyone has one running or not I would like to check it out.

I am looking for a reliable motor that will pull down some extreme fuel mileage in a daily driver with some fun factor. I am planning to use it in a CRX with a small turbo with around 200 to 250 HP at the most.

One of the things I read is listed below.

http://www.hondamarketplace.com/showthr ... ?t=2699294

Thanks for you input in advance. Dave

noob to Honda's but not to turbo cars.

[JustRob]

Interesting build idea.

If you can find the engine, then go for it. There is plenty of info on how to properly wire the 3 Stage VTEC solenoid. Other then that, it's no different then the other D15B's. However, you could find similar results using a D15Z1 or really any of the other D-Series engines.

The only other thing that could pose a problem is that reliability starts to become an issue after the 200 WHP mark on most D-Series as the rods and pistons are very weak.

[re-evaluating]

Well it seems from what I have read that the D15B is somewhat unique in the function of the 12 valve and lean burn plus the addition of the third stage for the top end. I don't expect it to be bad fast at all, I own a turbo Buick that qualifies and fills that need. I am most concerned with fuel mileage and think the small turbo will make it even more efficient and achieve higher fuel mileage. The bonus is it will be a lot more fun when the go pedal is used for fun as opposed to the daily trip to work. I drive 75 miles with only a couple stops through the country so just looking to save some money on gas and spend it on other stuff. I don't plan to run a lot of boost will keep it down again aimed at making it more efficient.

I found a motor and LSD trans that I am thinking about picking up this weekend.

Thanks for the input, Dave

[JustRob]

Seems like a lot of time, money and work just to get a couple extra miles per gallon.

The CRX HF was originally rated at 49 MPG City/52 MPG Highway. With the use of a well maintained D15B6 swap (CRX HF Engine, Transmission, ECU), proper aerodynamics, tires and driving habits, you should have no problem achieving that same fuel economy if not better. IMO, this is the better option as parts can easily be found, unlike the D15B. It's also an easier swap, less time consuming and nicer to your wallet. Is it going to be quick, no. But that should be the least of your worries considering the other vehicle you own.

Again, just my opinion. If you're itching to do this project and don't have any problem with investing the time and money, then go for.

[re-evaluating]

Well I have an HF D15B6 that I was going to use in my Si but with the increased weight of the car (Si compared to Hf) with the 2.95 final drive I figure the thing is going to be a real turd. I thought I might add a turbo to that motor and at 5-6lbs of boost to wake it up a little but then found the newer version with 3 stage vtec.

I do plan to use the HF trans with 2.95 final at least for a while to see what effect it will have. My 8400 lb dually diesel gets 27 mpg and makes 850 ft lbs, the more power I make to a degree the more efficient it gets and mileage goes up.

I am kind of itching to do it and see if I can pull off even higher mileage than the HF. There are some who "claim" to have gotten over 70 MPG, I don't know if it can be done or not but might be fun and challenging to try and see what I can pull off.

I am not that worried about the dollars invested, it seems fairly inexpensive considering I have a lot of the parts already. Have you ever priced 9 second Buick parts? LOL. This is really cheap in comparison.

I don't have to pay any labor, I can do it all myself, mechanical, electrical, and tuning as well, so other than parts not a lot of expense.

I am over 50 and I prefer to build an old inexpensive (relatively) toy for mileage than buy a new one that will likely be disappointed with. I enjoy the mental challenge seeing what can be done with a little ingenuity.

My biggest concern is issues with the motor over a USDM motor and if anyone has first hand experience with the 3 stage vtec.

By saying that about first hand experience I don't mean in anyway to sound unappreciative of any input not related to experience with the D15b.

Thanks again, Dave

[opntrk86]

I was considering using this motor in N/A form in my DD. I've done a bit of research on it, but ended up going another route

"suspendedhatch's" thread on gassavers.org has some good general info

http://www.gassavers.org/showthread.php?t=7011

I also had a few conversations with "FullRacePhil" via PM and he was happy to answer the questions I had.