B18C_EJ8

Hey guys... Dumb question maybe, but I know little to none about forced induction...

If one builds an all motor car, but then decides to go boost, would you be able to swap the head over to a bottom end built for boost? Head has been ported and is running Skunk2 stage 2 cams etc...

boostfeen

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18C_EJ8 &raquo;</TD></TR><TR><TD CLASS="quote">Hey guys... Dumb question maybe, but I know little to none about forced induction...

If one builds an all motor car, but then decides to go boost, would you be able to swap the head over to a bottom end built for boost? Head has been ported and is running Skunk2 stage 2 cams etc...

</TD></TR></TABLE>

..switch the cams for oem. ie: type r or gsr

B18C_EJ8

What's the reasoning behind that? Will they allow too much air/fuel in for boost?

93supercoupe

no, after tuning it , itlbef ine

bnut510

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18C_EJ8 &raquo;</TD></TR><TR><TD CLASS="quote">What's the reasoning behind that? Will they allow too much air/fuel in for boost?</TD></TR></TABLE>

swap em up for a good pair of turbo cams.... all motor cams have different duration. hope that sounds right

Monstah

The overlap on the N/A cam is usually a bit too much out of the efficient range for a turbo app. But if you can degree the cam to about 10-12 degress overlap, use them.
As for the head...if any extra material was welded in to increase compression, you may want to think about getting a different head for boost. otherwise, let'er rip.

crawlin

i doubt anybody would weld the head for higher compression on a honda thats why people change out the pistons.

but a ported head will be good for a turbo skunk 2 stage 2's might be kinda big for a turbo people have gone pretty far with gsr cams 500whp +

B18C_EJ8

So maybe I should hang on to these GSR cams I have lying around??

CRX_1.8T

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18C_EJ8 &raquo;</TD></TR><TR><TD CLASS="quote">So maybe I should hang on to these GSR cams I have lying around?? </TD></TR></TABLE>

Indeed, not a bad idea.

EARLdaSQUIRREL

why not try the cams out, ha ha do a head to head comparison on the dyno and see if they make more power than gsr cams, also dont forget to do cam gear tuning... id be willing to bet they wouldnt hurt power much if at all, i mean look at people using type r cams and having great gains over gsr cams

hybrid_KJ

Might want to have a machine shop check the valve margin on the exhaust side. Some head guys will run different margins on N/A or F/I heads and there could be some longevity issues running a smaller N/A valve margin on a turbo app.

redtegger03

Generally if you have a head built for turbo (ported), the port job will not be the same as a port job done on an All motor car.

Because of this, your going to most likely lose performance. As far as switching the cams...if your all motor and you go turbo, and are sticking with stock honda cams. The oem type r(2000) or ctr cams are used very regularly in turbo setups, proven to make more power over a turbo grind camshaft.

switching from forced induction to all motor, depending on your setup, you can get some pretty aggressive all motor cams...skunk 2 pro 2's for instance, your going to need pretty high compression &gt;12:1 to run these and make good power.

Which hopefully you would realize a 12:1 compression turbo motor probably wouldnt last very long haha.

So keep in mind, if you build your car for turbo there are alot of variables that wont mix and match with an all motor setup

KeyserSoze

If you're just trying to use the head, you should be fine. Typical turbo comp pistons are clearance friendly, but it never hurts to have the clearances second checked. As for the valves, you might need to ask someone who does porting for a living or one of the more knowledgeable people here on h-t. You would of course need to know what exactly was done to the head so that you can give someone all the info needed. As for the cams, just make sure the valve lash is good and have the tuner dial out whatever overlap he deems necessary. A good tuner will already know to do this when you tell him your running all motor cams. It seems like people think stage III cams are a bit much but a lot of people run stg II n/a cams. I am one of them. I have stg II crane n/a cams in my gsr right now. One of the links down below has my dyno and setup. Made 315 @11psi on a holset with a .65 a/r turbine housing. The tuner made NO adjustments to my cam gears. The power seems good for the boost level imho and my "crazy all motor cams with duration that will not work for a turbo app."

I have had pm's from well known tuners saying that I could probably get a lot more power just by dialing in the gears. Maybe when I get to the dyno sometime here in the next month or so I will have them do a baseline, and then have them adjust the gears and see what kind of gains I get just from that change.

And no he doesn't need 12:1 cr to run sk2 stg II n/a cams in a turbo motor, I think that assertion might be a little off track.

Here are some links to what you are asking (well some of what you are asking). All I did was search the fi forum for "all motor cams" and checked the archive option...........

https://honda-tech.com/zerothread?id=1309983
https://honda-tech.com/zerothread?id=1839185
https://honda-tech.com/zerothread?id=1119260
https://honda-tech.com/zerothread?id=1067466

GL.

redtegger03

In case you didnt notice i said skunk 2 pro 2....thats a big difference between the regular stage 2's...and yeah he doesnt "need" 12:1 compression to run them...but it would be a waste of a set of cams because he wouldnt be making close to the amount of power he should be if the motor was set up correctly. This is speaking in N/a Terms, not FI

KeyserSoze

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by redtegger03 &raquo;</TD></TR><TR><TD CLASS="quote">In case you didnt notice i said skunk 2 pro 2....thats a big difference between the regular stage 2's...and yeah he doesnt "need" 12:1 compression to run them...but it would be a waste of a set of cams because he wouldnt be making close to the amount of power he should be if the motor was set up correctly. This is speaking in N/a Terms, not FI</TD></TR></TABLE>

LOL!! Don't try to get smart with a dumba$$. Why are you gettin' feelings when the statement I made was put so gently?? I could have been much more curt than I was. That being said......

Firstly, I don't really see how discussing skunk2 pro's in an n/a engine applies here. Last I checked he doesn't have those cams. And secondly, he is not going to b n/a so I don't really see the topicality of your statement about said cams, n/a status and cr. I am very appreciative of the fact that you are talking about imaginary cams in an imaginary setup that this guy might have in his engine bay if he was going to be n/a, use really large n/a cams and have the headwork you presume he has.

As for the loss of performance, well, why don't we let him tell us who ported the head and what kind of port it was. Many people who do headwork don't even flow bench the heads they work on (not that the flowbench is the end all be all). And some of the guys who use flow benches are looking only at bulk flow/flow velocity and not even considering flow quality. He could have one of those $500, dime a dozen ports that really don't really even increase performance as the porting diminished the flow velocity/bulk flow (no way to tell without flow beching the head) and converted the flow into more of a turbulent flow than a laminar. The porter is the only one that can tell us exactly about the flow characteristics of this head. Maybe it will suck for turbo (no pun intended) and maybe it will be quite efficient. Perhaps you might know who ported it and the methods use in the porting process and could expand our knowledge of the afore mentioned head and how conducive it is to a forced induction application.

Ok, its late and I'm at work. Tired as hell and goin home. GL.

B18C_EJ8

I totally forgot that I started this thread..

Recently found out that my car is burning tons of oil, so I'm thinking of doing a rebuild this winter, and while I'm in there, might just as well build it for boost..

Anyways... To answer the question below, Endyn ported the head this spring, and installed new valves & springs...