B20b and RPM

[Dark93DX]

What RPM can the stock B20b block realistically withstand? abviously its close to the stock redline, but how much farther can it be pushed?

I'm asking b/c the head will be PnP with Crower 403's and the cams are good to 8500rpm or so.


Thanks,

 

[Dark93DX]

Is it worth it to get a block girdle?

 

[Dark93DX]

are the rod bolts on the Non-vtec engines netoriously weak? I know that vavle float is a issue, but not sure about the bottom end.

 

[dtob]

ARP rod bolts and type r oil pump. Rods are good.

 

[Dark93DX]

k, thanks.


BTW where is the major flow restriction in the B20/B18 head? is it more to do with the IM or the ports? I plan on bolting a Skunk2 IM to the head so I wanna know if its worth it to do a PnP afterwards?

 

[Dark93DX]

It's both. The ports in the head are small and the IM is (somewhat) port matched to them. Just putting a larger IM on might make the butt-dyno happy in the high rpm but the real dyno tells a different power story.

um.."butt-dyno"??

 

[dtob]

It will feel faster............. ;-)

 

[Dark93DX]

gotcha, so the ports should be matched to whatever IM I plan on using.


If I could steel your advice again....

I'm really trying to figure out what is gonna be a better route, bang for my buck & more effective. with my b20 swap, it makes good power down low, but I want it to breath better up top.

Option 1. using the b20 head, but with Skunk2 IM, Pnp & crower 403's


Option 2. using a VTEC (B16a) head (b20/vtec), but replacing oil & water pumps as you mentioned earlier.


Thanks,

 

[dtob]

CRVtec will give you more bang for your buck. Use the Vtec head and port match the IM to it or buy a skunk2 IM for even better results. Will cost more but will make a lot more power.

 

[Dark93DX]

Thanks for the advice.


...but, BTW are the crower 403' or 404's just as good in a B20Z (9.6:1 CR) as in a B18b LS setup?

 

[Dark93DX]

"Good" depends on flow.

I was thinking more in terms of the CR. Is to the B20Z's CR a little too low for a 403 or 404 cam?


I could upgrade to 11.8:1 compression pistons, don't know if that might be overkill.

 

[Dark93DX]

The way the head flows is far more important to making power than compression is.

I was looking at the CR b/c I want more aggressive cams. don't aggressive cams (eg 404's or VTEC head) require a higher CR?

 

[Dark93DX]

Thanks for the write up. I think I'll leave the bottom end stock and focus more funds on the head to extract some extra power.

 

[Dark93DX]

Speaking of raising CR, what type of tuning should I be looking at here?

 

[Dark93DX]

For porting and polishing, how big should I go? what manifolds do I get it matched too cause most bolt-on parts will be matched for the old smaller port size, can I use the intake and exhaust manifold from a VTEC engine?

 

[Dark93DX]

I'm not too familiar with porting and polishing so any help would be appreciated with selecting manifolds to match too.

 

[Dark93DX]

Hey thanks for all the good info. I've been searching around the internet, but it gets a little frustrating when ppl who don't know what they are talking about tell you to "just slap vtekk on there yoo, then turbo that beyotch for mad pwer" as if its that simple or reliable.


Back to my setup, after doing research and considering my budget and needs this is what I've come up with:

B20Z (9.6:1 CR) w/ LS ECU
Skunk2 IM
PnP head
Header (prb DC sports) + already got cheap intake, high flow cat & magnaflow ss cat back exhaust on the car.
crower 403 cams

If I've left something important out please let me know. (Apexi - VAFC?)

The 2.0L's give me the TQ i want for my dd and the head work + cams hopefully give me a little more top end power as well. I don't plan on raising the stock LS redline though.

 

[Dark93DX]

are you using ARP rod bolts on you D16Z6 or just the stock bottom end? obviously I would need to have the rods resized if I replace the rod bolts, would the machine shop need the crank also in order to resize the rods?


Also about the milling, I was trying to figure out how much they would need to mill off in order to bump the CR to 10:1 and I came up with 0.01634", but I have no idea i i'm right on this.

 

[Dark93DX]

Good to know. So I'll be adding ARP rod bolts to my previous setup, i guess you can never overbuild an engine. Now I gotta turn my attention to tuning.


Thanks Blanco,

 

[Dark93DX]

You're welcome. Good luck, man.

Thanks, there is WAY too much wrong info out there, you have no idea how refreshing it is to talk to someone who actually knows his stuff.

When I get it all running I'll owe you a drink.


Cheers,