I do some Honda work. I have a machine shop and do racing engines. A customer came in Friday and wants a motor for off road racing. It can be no more than 1800 cc and non turbocharged. First I thought of a Rabbit as they are pretty tough and then the Honda. I am thinking B18 Honda might be a good choice and specially with the availability of the Dart B18 block. Seem to be plenty of aftermarket parts available for the engine. The plus is Honda parts are so well build that the aftermarket may be a waist of money in some cases. What engine would you guys use with the limit of CC and looking for good HP and a lot of durability? Also thinking about a carbuerator for simplicity. If we cut some weight and go to a longer rod and forged piston it should make a pretty killer little combo.

 

I would suggest any of the B18C's..GSR or type R really.

 

First off, what type of trans is your customer going to run?

Majority if not the entire B-Series family is CCW (counter clockwise) rotation.

I have built numerous sand rail and off road B-Series engines, but all of my customers had Mendeola or Fortrin trans that can handle the reverse rotation and suspension travel.

I would suggest a K20 destroked and sleeved with a smaller bore to get you under the 1800cc mark. You can't beat the flow of the K20 cylinder head. And the K-Series are regular rotation. I would think the cost of a good used K20 block, sleeved and a destroked crank would be really close to the price of that Dart B-Series block.

 

I would just go with a LS Vtec motor, B18B1 bottom end and a GSR head with P30 pistons. This is a good low cost setup that can make great power and good TQ for a 1.8L. The B18B crank and rods will give you a longer stroke and the P30 pistons will put compression at around 12.5:1. With the right head work and cams and of coarse tuning a LS Vtec will be in the 1800cc limit and be a killer motor.

 

The first question we need answered is the application and trans that will get used?

He stated off-road so I am assuming a buggy, short track car, sand rail, etc. The reverse rotation of the B-Series can be a nightmare if the proper trans is not used.

Just my $.02

 

I'd stick with the B-series and not go through the hassle of "destroking" a K20 setup, which adds significantly to cost. THis is an off-road setup, meaning that its going to go through some hell and will be maintainenced a lot, even with the stoutness of the B-series engine as it sits.

As stated, the B18C, B18C5 (more rev happy) are best. If you want additional stroke to the engine, simply substitute the B18C crankshaft with one from an LS (B18B) with aftermarket LS length rods. Going to a carbuerator won't be an option for that engine. The entire use of the engine is based upon injection at a higher RPM rate than any carb could account for. DOn't try and convert. Tell your customer that he needs to get the car computer tuned.

 

euro r h2b

 

He must stay 1800cc.. Am I the only one seeing this here? Or is there some new H-series that's actually the same size as B18C that came out in Europe?

 

Reading > you.

 

Just an FYI, if this is a spec class, there is a good chance it is carb only, no FI allowed.

And to offset grind and heat treat a crank is only $400-600, custom rods are $600-800, If that. So I wouldn't call that a significant cost increase. Especially if he is thinking the Dart block option at $2500, block alone.

The OP hasn't even answered the question at hand, what application? What trans will be used?

There shouldn't be advice given since we don't know the application yet.

I take it you haven't built an off road car before?

The trans is one of the most over looked parts in that type of vehicle.

And a reverse rotation engine will only take the higher end trans like a Mendeola or Fortin. Which start at $5500 and go up to $15k.

I have been there and done that. Only trans that will work is one of the two mentioned above.

Good luck.

 

Thats actually not true.. i am running a VW bus trans on my B20vtec turbo Sandrail right now.

 

It's true in the Pro Buggy Unlimited class that's part of the Lucas Oil Series.

 

Aww. Yagotmeh. Did not read lulz.

 

You forgot the K series VTC, which helps keep torque high (to a certain extent) no matter the rev range.

 

What class is he racing? I think it's class (might be wrong) 10 or 1/2-1600 (buggy) most guys run the b16. Due to higher revs and with the dirt and the top speeds of the desert the low end torque of the b18 is not going to help much. When your sliding around your going to want something that can be rev'd. Another question is will you be able to even use the vtec? B16's are a dime a dozen and can be replaced easy. A b20 vtec 1. Is over 1800cc and 2. The cyclinder walls are not strong and since that motor will be in high to very high rpms most of the time I would stay away. Also IMO your asking this question on the wrong form you need to hit up race dezert, most of these guys are going to tell you info based on drag racing or stop and go racing not sustained high speed racing (unless they road race). And even road racers slow down, desert racers only slow for 2 reasons they need to pit or they broke.

Just my 2 pennies.

 

Its true that they only use mendeolas or Fortin in the class you are talking about (not that it has much to do with what you said) but ok.


You said that those were "the only 2 that will work on a reverse rotation engine" (Not true) doesnt mean nothing else works.

Its just preferable of course to have a mendeola or fortin.

But there are other options besides spending $5000+ on a mendeola.

 

I haven't asked the actual class that he is talking about. Sounds like it might be the Lucas oil series. He does high end VW stuff and is going to use a VW transaxle but it will be custom built and we can do any ratio we need. I think a carb would be best as we can work on it in the desert so if there is no provision for a dist it would make it tough. Hp is important but I have built some other Baja efforts and one big thing is having enough torque to pull it through a lake of soft silt as the race goes on. The other thing is that finishing is most important then torque and hp. I build stuff for pulling and funny car and if you can't make power for 1320 ft with a funny car its hard to win. Well with an off road its even more important. I appreciate the discussion and am amazed at the different opinions about the best engine. You guys could save me a lot of R and D money. Money for the project is secondary. When customers tells me they have a budget I tell them everyone does. Robby Gordons is just bigger than my customer but it will be a fairly serious effort.

 

One other thing. I happen to be a member of this sight instead of the off road. Never even thought about one of those sights. An engine is an engine. They are all a math formula and have strong and weak points that need to be addressed. I think sometimes being outside the box is sometimes good. Dick Maskins told me that if I look at what everyone else is doing I am destined to run slightly slower than them. I took it to hart and won the nationals the next year.

 

I think especially with the way these are designed, you're better off with one of the older carb'd based hondas engines from 1987-88. The entire design of the B-series VTEC and K-series that are described are based solely around distribution and Fuel Injection as its central premise.

We just may be a bit out of your league for what you need to accomplish.