tired of all the bs threads in here just like every one else.

lets discuss the differences between the non vtec b series ports, valve angles, seats and intake manifold design to a vtec head.

we all know the ls heads flow like garbage and huge gains can be made from a simple head swap but lets find out why..

intake manifold:
the ls intake manifold has much longer runners and a smaller plenum. I have both in my hands at the moment and I will be taking measurements of each later tonight. I know alot of power can be had from a simple intake manifold swap. I had a ls turbo last year and I put on a xs power itr rep intake mani on it and added in a considerable amount of fuel from 6400-7400 (the old intake manifold used to feel like it hit a wall at 7000) the car went from trapping 116-118 to 121-123mph.

port design: vwbased was nice enough to make a mold of each port that can be seen here http://www.google.com/imgres?imgurl=...1t:429,r:0,s:0. as you can see the pr3 is not only bigger in volume but also has a much better short turn radius, there is also the issue between valve sizes being the ls is 31mm intake vs 33mm. Im just learning about port autonomy so feel free to add your knowledge here. for some reason I have a huge fascination with non vtec b series heads. I would like to help use this thread to gain knowledge to help me better my head.

cam design: only having one lobe size per cam definitely simplifys things but it also makes these heads very limited from the start.
B18A1 (90-91)

Camshaft specs:
IN: 1.3160
EX: 1.3083

B18A1 (92-93) B18B1 (94-95)

Camshaft specs:
IN: 1.3274
EX: 1.3083

B18B (96-01)

Camshaft Specs:
IN: 1.3274
EX 1.3200

b series vtec: (taken from team-integra, quick google search)

STOCK GSR : b17a and b18c1 -(I know gsr and b17a1 cams are different)

INTAKE lift - 10.6 mm,duration - 230 @1mm
EXHAUST lift - 9.4mm, duration - 227@1mm


- STOCK 1997-1999 ITR
INTAKE lift - 11.5 mm, duration 240 @1mm
EXHAUST lift - 10.5mm, duration 235 @1mm


- STOCK CTR and 2000-2001 ITR
INTAKE lift - 11.5 mm, duration 243 @1mm
EXHAUST lift - 10.5mm, duration 235 @1mm

-link for reference -http://www.team-integra.net/forum/blogs/michaeldelaney/28-vtec-cams-specs-comparison-bseries-engines.html




I will keep adding to this thread as I do more research.

any one know stock valve seat angles?

 

It has nothing to do with the angles or size of ports or anything like that. The LS/B20 stuff is inferior due to the design of the valvetrain. You can port the hell out of anything but it's still going to be a time bomb if it can't stay together past 7500 rpm.

 

general consensus is that the ls heads are good to 8500rpm with proper valve train. its just hard to get them to carry the tq to that sort of rpm. thats why Im trying to figure out how to better what I have.

 

buy a different head. sometimes thats all you can do.
i'd like to better the torque in a b16a to the limit but that just isn't gonna happen.

they were designed that way.
a b16 has short gears no torque and needs to get to 8k all day.
a b20 has super torque and has no need to hit 8k all day so it isn't built with the intent to ever handle it.

to me in simplest form thats why.
but im not an engineer and still pretty new to the game so i might get smacked down with knowledge we'll see.

 

I feel like this a pretty standard feeling on honda-tech of the ls heads. I know you can make them into really fun street motors with just a little work so Im trying to figure out the best way to do that. you say you can't get tq out of a b16 and that is true to an extent but the stroke is the limiting factor in that. the ls motors already have the displacement you just have to open them up to get the power out.



and Im not debating that a stock vtec head will in most cases be better then a built and ported non vtec head. I just wanna figure out what the best things you can do to them are.

 

Might want to read this thread all the way through:

https://honda-tech.com/forums/all-motor-naturally-aspirated-44/project-ls-non-vtec-begins-1765855/