I have a B20 with a P8R head on the way and I'm considering any mod that will improve power without sacrificing mpg and even better improving mpg and power.

 

That will come from a good tune. Not cam profile.

 

So a wild cam that allows me to rev to 8500 rpm won't hurt mpg? Not that I want to do that but better cams are of interest if the power can be added without mpg sacrifice.

 

Curious what makes you think you can throw cams in and rev a b20 to 8500....

 

No I don't...the cylinder walls are too thin and the head doesn't flow well enough etc etc. My point was to say that I think cams do effect mpg adversely and that my post is about at what point of wildness of cam do I start hurting mpg if I can at all since my engine doesn't rev that high.

I've been recommended to use a 403 cam I think but I have no idea how that's going to affect gas mileage. Help, hurt or no change.

 

I have a B18 with 403 cams and mild tune getting 30+ mpg. I could adjust the cams, intake, and tune and get a whole lot more. Fuel economy is in the driving style and the tune. If you want better mpg and power, go VTEC.


Posted from Honda-tech.com App for Android

 

And what you've said about the cylinder walls and head isn't accurate. Stop listening to ricer noobs.


Posted from Honda-tech.com App for Android

 

U can use some B20Z cams or LS cams.. just a tad more lift then the B20z.

If your going for MPG's then why are you trying to add performance parts?

 

2000 intake cam from p75 ls head best cam for power and mpg if your in miame let me knoe have my old one for sale..if u want to see that b20 made 162 hp stock assy
youtube.com/bowman18c/ 30 bucks and its yours

 

Engines not in and if I'm going to increase power I want to do it now. More power without sacrificing miles per gallon is never a bad thing. It won't be fast but it can at least be faster.

My current stock d16y7 engine has 330,000 miles on it gets 30mpg (yes it has a check engine light on) and will be at the end of its life soon. If I can have an engine that has 150whp and gets the same gas mileage then I've got an upgraded car that I can live with a lot easier than I can with the one I have now without swapping cars.

 

then leave it alone..

you can have performance or MPG's so pick one.


If you want to change the pistons to the higher comp 9.6:1 over your low compression ones, PM me
I have a set of the PHK pistons and a new set of hastings rings.
you have slightly better MPGs with the higher comp ratio, more HP and Tq, and better throttle response.

 

It's been proven that the stock sleeves don't hold up well to high revs. And the head doesn't flow well at high rpm. So non of that is inaccurate.


Then just leave it stock

 

My b20 has the P8R head so it has a little better flow than the average stock b18 and b20.

 

not by much.. the P8R has flow issues beyond 400cfm.. I have the P8R as well. Check the block stamp underneath near the oil pan bolts. see if it says P3F or PHK





i cant believe this thread is still going.

 

It's been proven that poor tuning blows up stock sleeves but many people have these blocks stock and rev to 8k+. The non-VTEC heads don't flow as well as VTEC heads but he's talking about a relatively low power range where the effect is not nearly as great.

 

I'll bet with a good tune and not hammering it all the time you can get the 30mpg on the 403's. They're fun too.

 

Yeah I'm thinking cams and pistons are out of the question. I spoke to the shop about it and they said that cams 2000 ls cams were probably not worth it and I'm thinking PHK pistons are just too much extra work for that extra .4 cr I'll gain from them.

 

I think the LS cams are worth it. Its not like theyre expensive. But the little extra lift they provide is better then what you have now. And its OEM.

You can pick some up in the marketplace for 20-30 bucks.

But its your build.

 

Well you've got a good point so you may have talked me into it...I'm going to think about it a bit more.

Do you know wher I can find a spec sheet on the different B20 engines? I'm really curious what B20 cams I do have since my engine came with a P8R and 9.2cr...I believe that pretty much means it's JDM...oh it came from hmotorsonline.com

 

google B20 P8R and get comfy

 

I like to use Google image search for things like "stock B20 dyno sheet" and get a lot of info that way.

 

This link shows the cam specs from a 96-98 B20 vs 99-00 b20z. It looks like the intake side on the 96-98 is just a tad less aggressive but it looks so minor I don't think it's worth it.

 

What link?

 

oops I forgot the link
http://www.importatlanta.com/forums/...questions.html