ITR1071

When raising the compression on SOHC motors, is there a certain number of horses you should gain per increase in compression?
For instance, if I raise from 9.0:1 compression to 11.0:1 compression how much hp should I expect to be a added?

How much can I expect with port and polish, 11.0:1 compression, and upgraded valve train?

B18C5-EH2

I think it's cool that you're asking questions about the SOHC motors, but could you please keep it all in one thread?

You could probably ask an entire list of questions about a specific SOHC motor in one thread rather than having 5 different topic with 5 different questions about the same exact motor.

Not bitching really, but it will probably help you out more if you consolodate your questions into one big thread.

ITR1071

So you think that all motor applications would be more powerful on a SOHC motor vs. a DOHC motor?

The GreenD16

as a fellow SOHCer, i would also like to know...

EVIL Hx Coupe

No Way!!!!

93delsol

you can find better info here http://pub34.ezboard.com/bhondadseries It's a D series board and you won't get the "Just swap your motor!" replies on there

Smashback

He's right. For a streetable engine it'd be REAL tough to get 150 WHP out of a D16Y8 or whatever the one that came before it was...D16ZA or whatever.

You'd be looking at a massive head work...biggest port job you can get, 5 angle, monster cam that idles like crap, highest comp you can run on 92, etc.


EDIT: It would cost more and be more work to get 140-150 out of an NA SOHC than it would be to turbo it and get over 200.


[Modified by mplex2000, 5:11 AM 9/20/2002]

Zeus Zore

you dont even know the engine code !! yet you talk about power in one !?!...

i do not agree i think goin N/A is the honda way !! **** a turbo car when im N/A cause i could do the same thing !! getting HP out with N/A i think says more
not easy !! but easy come easy go !! ;-) same thing with turbo !!

i think 150 WHP is not that hard !! dont need that all head job and some stage 5 race cam !!

turboman

I don't see why you couldn't get the same or more horse power out of a SOHC motor. Smaller, Lighter, and one less cam to turn. I always wondered if you raised the Rev limit up a 1000rpm if you would get more power or equal the power of a DOHC.

Will I get flamed and have a series of numbers and ratings thrown at me now.

JaeOne3345

not really, its all in how much thought u put into it. and it isnt always about power numbers. i know of 2 personal friends in the 13s with less then 150whp non vtec sohc's. and i got another making around 163 with a y8.

biggest porting does not always help. and the 13 second car i know, idles fine. comp ratio? stock bottom end with reshaped chambers. not even close to the max u can run on 92.


then again. hp is not what everyone is about. some people are into different types of racing. no everyone needs some 200hp motor. i dont really want a 200whp turbo motor at autox, cuz thats not what works for me. it works for you i got friends with turbo single cams making about 200whp. and not ALL of them are hitting 13.6 like wil (ht user: exospeedAMcrx). he did 13.6 on stock bottom end. yes he had a nice head, yes it was on slicks, but i guarantee he did it cheaper then the cost of a greddy turbo kit.

no way is one better then the other. its all in where u a are at for your needs, not how u get there. that way works for him, your way works you. PREFERENCE i just find a lot of times people tend to shut all motor sohc out of the window with not even givin it a chance at all, when its very possible to make them damn quick. going fast takes thinking, how much do u wanna study? ever seen those quick *** ITA crx's run road races? its hard to say those cars aren't fast.


[Modified by JaeOne3345, 11:34 PM 9/19/2002]


[Modified by JaeOne3345, 12:19 AM 9/20/2002]

ExospeedAMcrx

UndercoverSi:

back to your question, not all SOHC motors react the same to each upgrade. The VTEC sohc's are harder to get more power out of with cams than the non-vtec.

The non-v cams can push out extra HP out of the motor up to 15whp to the wheels.
a basic head work on a non-v with bolt ons and cams can bump the whp to 30+HP, thats 40HP or so gain with out even touching the bottom end.

The VTEC cams arent as great but you can still get 150 or so WHP without touching the bottom end.

Keep in mind my HP figures are without Milling the head. I personally dont believe in milling heads.

With a good bottom end for either VTEC or non-vtec SOHC's, you can push a good 160-175HP to the wheels.
I would love to do more SOHC build ups but most of the people that come to us are budget minded and are only doing head packages. We understand that redoing your motor is a big step and not everyone can dump loads of cash into their cars. and thats why we make our head packages worth it for our customers.

Undercover, from what you said, "How much can I expect with port and polish, 11.0:1 compression, and upgraded valve train?"
to me, the main focus on an SOHC should be the camshaft. This is what will make the big difference in the motor. THe rest just complements each other, but are also very important parts of the upgrade.

Before bumping up the compression, I'd work on the head first and then do the bottom end. high compression is koo, but its full potential can only be used if the head is supplying it with the air it needs.
good luck, sohc fans.

Wil

After 3 yrs of hiatus, we are bringing out our sohc cams again.
4 diff grinds for the D16a6
2 grinds for the SOHC vtec

sohc_boy

Wil any chance of a cam for the y7?

Mista Bone

to answer the orignial question, expect a 3-4% gain in power output with every point higher compression.

This is true to some extent, but at about 13-14:1 compression, you get diminishing returns.