350x head porting (picts)

[boosted96cobra]

This is another members 350x head. Some of you that know me know I used to do alot of import head porting. I have been wanting to to see what power can be had out of a 350x for a while now, considering it is the almost same configuration as an acura integra 1.8, even down to the bore and stroke and similar valve size. I do have a fw finishing touches to put on this, but I figured some may be interested in the progress. I have always ported not for max flow which can only = peak numbers, but for useable power increases. If you can't use it, then what is the point.

Anyways here is some of the work in progress:

http://i291.photobucket.com/albums/ll292/sagep11/IMAG0022-2.jpg

http://i291.photobucket.com/albums/ll292/sagep11/IMAG0023-2.jpg

http://i291.photobucket.com/albums/ll292/sagep11/IMAG0024-1.jpg

http://i291.photobucket.com/albums/ll292/sagep11/IMAG0025-1.jpg

[AutoXer]

looks good are you going to be able to get that bent exhaust stud out?

[Dirtcrasher]

Nice!!, I see allot of "smoothing" done in there which is great!

I've heard how bad an average guy can screw up stuff with "self-porting" so about all I'll do is match ports and smooth stuff up.

Are you able to do any flow testing?? Apparently thats the real test for this stuff.

I bet there is a TON of potential with a 350X just in porting, mild cam and a decent piston.

Keep us informed :beer:

[The Goat]

it's very very pretty...hmm

[boosted96cobra]

Nice!!, I see allot of "smoothing" done in there which is great!

I've heard how bad an average guy can screw up stuff with "self-porting" so about all I'll do is match ports and smooth stuff up.

Are you able to do any flow testing?? Apparently thats the real test for this stuff.

I bet there is a TON of potential with a 350X just in porting, mild cam and a decent piston.

Keep us informed :beer:

I have used flow benches in the past, even owned a cheaper one, and to be honest they really didin't do much good. I mostly used them to keep cylinders flowing about the same, which were all pretty close already.

With any stock head there is things you can do to add power everywere. For a 350cc you can go to a certain point and then after that it is give and take. Sure if it a diffrent cc like a 395 a little more can be done. But after that it's give and take, and what I mean by that is:
say you get a big stage 3 cam for your stock 350x and install it. What you basically did was increase top end (hp#'s), but lost low end and idle. Give = top end, take = low end. Sure you added a few peak hp, but everything under the curve (the power a 350x rides uses everytime he rides) most likely suffers. This is why they always recomend higher compression with a big cam, to get that low end punch back.

The same goes for porting. Sure there are some people who spend the big bucks and go for max flow, cnc ported stuff, and then spend the money getting every other part to make it really run. The rest end up being those dyno queens that everyone laughs at...."dude has $500 in porting and big bore and stroke and I just beat him on my mild home built bike". You know we have all seen those. I know a few stang guys that built their cars around the biggest is best too, all I can say is they were very disapointed.

The head above will be on a stock bore, semi mild cam and a 12:1 comp piston. I had recommended the 10.25:1 piston, but he went for bigger. Of course he was going for the biggest cam, highest comp "bigger is better, right?" stuff. Already it will be on race gas. Stock these run Sand Mountain in second, we are building it to run 4th or maybe 5th with some gearing changes.

[boosted96cobra]

it's very very pretty...hmm

We should be putting this on this weekend, so I will let you know how it runs. Hopefully if you game we can get yours done soon.

[Dirtcrasher]

^ Great info :D What are you gonna run for a carb on there??

I've got a couple crate motors and I'd like to tear into one and do some porting, mid range cam and 10.25:1 (because it's my daily runner, too much $$ for race gas constantly - unlike the 200X)

[boosted96cobra]

I think he is going to run a stock carb for now.

It's crazy how much crate or NOS stuff you guys have. Here everything is used and ridden hard. LOL

I have read threw most of your build threads ect. If you want any help porting pm me your number, I think i can help some.

[JohnR.]

It sounds like you're doing something similar to my X. 10.25 piston, mild cam, mild port job. I went to a slightly bigger carb (38mm) and a DG exhaust. It really woke the X up big time. It'll pull on a piped 250R now.

John

[The Goat]

that's very interesting coming from the above gent.

how fast was your R on the ice? I've always been curious.

can they run that fast on say...a gravel fire road?

[JohnR.]

When I said it pulled on an R I should have been more clear. Coming out of corners and blasting down short straightaways in the woods it would pull on my buddy's R that just had an FMF pipe and silencer on it. It would hang with the stock bore R's out on the ice on a small oval but the top end of the X wasn't good enough to hold them off on a big track with long straights.

John

[Dirtcrasher]

They're so completely different animals......

3fiddyX's have tons of torque and usable power down low and thats why I love em :D They are completely and entirely predictable.

R's have top end power and speed that get through things which may otherwise get the heavy "X" into trouble.....

Mine is still stock aside from a SuperTrapp exhaust and some jetting; it's quick and holds it's own just as it sits.

I can only imagine how much more usable power I could have with a crate motor - 10.25:1, mid range cam and a great carburetor.

The overall weight holds back a 350X........

Polishing and porting done correctly seem to wake things up INCREDIBLY!! I have cutters, polishers, grinders etc etc but I figure if I don't know WTF I'm doing that I'll probably just hurt it. So, I'll just pay someone who knows whats up (THAT in itself can be very difficult these days!!)

To me P+P is done by people that know what has to be done and how to do it. About all I can do is smooth some corners up and match ports.....

Sorry if I got off topic......

That polish alone on that head looks super nice!! I'm always up for tips though :D

[JohnR.]

A friend of mine does porting and machine work for a living, that's who did my X back when I did it (around 2000). IMHO the mid-range cam made the biggest difference, it moved the power up some. The torque that a stock cam makes right off idle is nice but how much time does the motor really spend down there when you're riding? I was happy to trade some of that off for a mid-range and top-end hit that blows away the stock set up. When he did the port work I was planning on using the stock carb so the intake tract is a little too small for the 38 I have on it. When I pull the engine out this summer to give the frame some TLC we're going to open it up to match the carb. That should help some too.

John

[The Goat]

you've got me salivating at the thought of what the motor will be like...

ya didn't answer me though, how fast are yall running on the ice? and can it do the same thing on just gravel roads, or would the friction hold you back?

[JohnR.]

I never clocked my X on the ice or on the gravel. I've had snowmobiles clock the R a couple of times on the ice. I got 107mph when the motor and studs were fresh 6 or 7 years ago. This year up at Raffa's the guy on the sled said it was only doing 100 but I don't think I was putting all of the power to the ice anymore, the studs were pretty much worn out. I never clocked it out on a gravel road so I don't know.

John

[The Goat]

Good god...

That would be dead sexy.

Sage, you'll be hearing from me again soon.

[boosted96cobra]

Awesome hit me up anytime.

[The Goat]

what about using larger valves for the 1.8 integra in this head?

[JohnR.]

I'd be surprised if the valves are the same length.