Civic-EG.com Forum 3.3.1

- Tue Oct 05, 2010 9:27 am #216922 Yo i have a stock b20b with bolt ons and i was wanting to do some engine work.
I was wanting to bore it out to a 84.5mm.
Just a guess how much hp increase would this bring me?
Im also going to go with forged pistons.
Im currently making around the 200hp mark.
Thnaks

- Tue Oct 05, 2010 9:50 pm #217006 Im not sure how a stock B20b with bolt ons is making anywhere near 200hp.

As for your question, it will vary. It really depends on what CR you will use, the tune, cams and lots of other things.

1986 Nissan 300zx
1980 Kawasaki KZ650
2014 Kawasaki Ninja 300

- Tue Oct 05, 2010 10:42 pm #217013 Im guessing you are pushing 165 max with just bolt ons but that's my opinion.

- Wed Oct 06, 2010 12:01 am #217022 Okay that makes sense but I have all baisic bolt ons full exhaust ect..bit just a guess. But would it be better to shave my pistons instead of boring? I have fresh forged pistons by probe

- Wed Oct 06, 2010 2:59 am #217051 What are you wanting to do with this motor?

With all the bolt ons you have about 160-165 at the crank. Not the wheels.

1986 Nissan 300zx
1980 Kawasaki KZ650
2014 Kawasaki Ninja 300

- Wed Oct 06, 2010 3:04 am #217052 im wanting to get the most out of my motor without building vtec or turboing

- Wed Oct 06, 2010 4:19 am #217068 I remember doing research for a build like this ... 200 whp is easily doable on stock bore. You have to be careful boring the b20 because the cylinder walls start getting really thin at which point the cylinder pressure can start causing problems ... my .02 ... leave the bore alone.

Anyway my build plan was to (first) try to source a p8r head. This head came on a few JDM b20s, specifically the ones found in the honda Orthia. Anyway the reason for choosing this head is that it has 1mm oversized intake valves (when compared to the p75 head found on the USDM b20). That is the only difference between the p8r and the p75 internally they are the same and so can use any aftermarket part that will fit in the LS/B20 head (if you want aftermarket intake valves I believe you have to get some for a prelude, but it's been a while). Moving right along ... you will also want to find a Type-R intake, and a good quality header. To top off this build I was going to run 11 - 11.5:1 CR and the crower 404 (3/4 race) cams. Pair this with a b16 or GSR tranny and you've got yourself a barrel of fun ... and 200+ to the wheels (you'll also need some 310cc+ injectors IIRC).

I found one or two dynos of similar setups and one what putting down 210 whp on a shitty tune ... running pig rich. So with that setup you should be able to make some good numbers.

Straight lines are for sissies.

- Wed Oct 06, 2010 5:23 am #217078 Why not slap a turbo on it? Your pushing 9.6:1 with stock pistons which is perfect for turbo. Wouldn't make much sense to go all motor since you redline at 6-7k.

- Wed Oct 06, 2010 5:23 am #217080 Thanks alot! this really will help me and i just so happen to have myself a gsr tranny in my eg along with a stage 3 clutch!

- Wed Oct 06, 2010 5:24 am #217081 well im thinking money wise i really cant afford a turbo set up right now

- Wed Oct 06, 2010 5:41 am #217082 You will spend way more money on all motor then you will with a turbo setup.

- Wed Oct 06, 2010 6:36 am #217089

Why not slap a turbo on it? Your pushing 9.6:1 with stock pistons which is perfect for turbo. Wouldn't make much sense to go all motor since you redline at 6-7k.

With forged internals (which he already mentioned that he had) and a beefed up valve train (which I forgot to mention, but was kind of implied) you can rev the b20 to 8k+ just like any other b series. The b20 is just a bored out b18 block ... you know that right?

Stock redline may be 6-7k, but with the proper mods you can spin it higher. What's the stock redline on an f22? And how high is bisi revving his?

He's not limited to stock capabilities.

And besides what's wrong with only revving to 6-7k? If that's where your power is, there is no reason to rev any higher.

If he wanted to go turbo ... he wouldn't have posted in the N/A section.

Straight lines are for sissies.

- Wed Oct 06, 2010 7:03 am #217093 Umm read the first thing he said he has a STOCK B20b he was talking about getting forged pistons. Also you would need to spend the money on rods and pistons in order to rev it to 8k+ which is expensive. On top of that he wants to bored it to 84.5mm which will need a block guard or sleeves. So why not keep it with a stock bore, keep the pistons, turbo it and save yourself the hassel and money of trying to push 200whp when you could easily push 250whp stock with a turbo. Also how much do you think it would cost to bore, hone, block guard, CP pistons, Eagle Rods, and new headgasket? About $1300 plus not including paying for installation if you don't know how to DIY with a lot of down time. So as I was saying turbo would be the cheaper route.

- Wed Oct 06, 2010 7:26 am #217094

Umm read the first thing he said he has a STOCK B20b he was talking about getting forged pistons. Also you would need to spend the money on rods and pistons in order to rev it to 8k+ which is expensive. On top of that he wants to bored it to 84.5mm which will need a block guard or sleeves. So why not keep it with a stock bore, keep the pistons, turbo it and save yourself the hassel and money of trying to push 200whp when you could easily push 250whp stock with a turbo. Also how much do you think it would cost to bore, hone, block guard, CP pistons, Eagle Rods, and new headgasket? About $1300 plus not including paying for installation if you don't know how to DIY with a lot of down time. So as I was saying turbo would be the cheaper route.

Guess you missed this post. And the fact that the first post was him ASKING if he SHOULD bore to 84.5.

Okay that makes sense but I have all baisic bolt ons full exhaust ect..bit just a guess. But would it be better to shave my pistons instead of boring? I have fresh forged pistons by probe

I sort of assume the OP is not an idiot and would get forged rods to go with his pistons.

And then I guess you also missed this post.

im wanting to get the most out of my motor without building vtec or turboing

He wants to go all motor. Admittedly this next post doesn't make any sense:

iwell im thinking money wise i really cant afford a turbo set up right now

Since a good solid N/A setup is going to be more expensive than boosting it ... at least the build I described.

I'm not saying that the turbo build wouldn't be cheaper or make more power. I'm just saying that the OP has chosen all motor as a build path and that telling him to go turbo is not in any way constructive. He's not looking to make the most power ... he's looking to make more N/A power.

Shit I'd rather have 200 whp N/A than 200 whp boosted any day, though I do love my boost.

Straight lines are for sissies.

- Wed Oct 06, 2010 7:43 am #217095 Does everybody on this forum look like Richie Rich? And can afford all the aftermarket parts, obviously he would've noted if he was buying rods since he listed other things. I was telling him an alternative route. It would would cost way to much to get 200whp out of the b20b and if he had the money for it im sure he would have done it already instead of asking about it. NA horsepower is wonderful but you can push more hp/tq with a bolt on turbo kit and don't need to worry about running high ass octane and wondering if and when pre detination is going to kick you in the nuts. A 500whp turbo motor can run on 93 octane all day everyday with a good tune but a built NA wouldn't even be able to run on anything below 98.