Peer pressure and the OHV - Page 2 - Performance Forum

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Re: Peer pressure and the OHV
Wednesday, April 18, 2007 4:30 AM
Well, we installed the guides and set the valves into the chambers last night to see how it looks. Niiiice. (Forgot the camera, again). For some reason the valve seats we intended to use for the intakes were among the missing and work stopped for the night.

The OHV build guide from GM spec'ed 1.457" exhaust valves and 1.80" exhaust valves. The valves I have are currently 1.50" and 1.88" but we're planning on reducing the OD of the intake valve to 1.84." There is a potential problem with the valves making contact during overlap with this combination. It happens with what appears to be very little lift. After some thinking I believe I'll use two dial indicators to measure the lift of each valve at the point where contact occurs. From there it shouldn't be too much of a problem to chart the intake and exhaust lobes of a cam to determine the amount of lift where both valves are open the same amount. If this point exists and if it's equal to or greater than the value I measured, then the cam can't be used. If the cam lobe plots cross at a lower value, it will come down to deciding what is an acceptable safety factor as to whether the cam can be used.

In all honesty my feeling is that the lift value where the valves intersect is much greater than the typical lift values seen during the overlap period for most cams.

-->Slow

Re: Peer pressure and the OHV
Wednesday, April 18, 2007 6:52 AM
I saw this same situation when I was measuring for oversize valves (valve ratio thread I believe). When I measured it out, contact was actually at a relatively high lift compared to the very low lift at cam overlap, so you should be okay.



fortune cookie say:
better a delay than a disaster.
Re: Peer pressure and the OHV
Friday, April 27, 2007 4:19 AM
BTTT

Intake seats are installed and machined, valves drop in. Cutting operation for intake seats brings edge of combustion chamber right to fire ring in head gasket. Exhaust valves fit in OE seat. Valves are at OE height so stock valvetrain geometry can be maintained. Spring seats will require minimum machining for "Z28" springs. Due to type and sizes of valves, the margins are huge meaning these valves could handle some abuse without troubles. Final valve head sizes are +1.1mm exhaust and +3.23mm intake. I'll try to get pictures very soon.

-->Slow
Re: Peer pressure and the OHV
Friday, April 27, 2007 7:45 AM
Holy bejesus!!! +3.32mm???




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Re: Peer pressure and the OHV
Friday, April 27, 2007 8:24 AM
Scarab (Jersey Jay 1.8T) wrote:Holy bejesus!!! +3.32mm???
Yeah, that would definately require opening up the chamber a bit.
Have you cc'ed the new combustion chamber yet?



fortune cookie say:
better a delay than a disaster.
Re: Peer pressure and the OHV
Friday, April 27, 2007 12:49 PM
Quote:

Holy bejesus!!! +3.32mm???

Yeah! lol

I'm going by the OHV build guide's dimension of 43mm for stock valve and what my friend reported as the final OD of the intake valve. They fit better than expected, and the cutter didn't have to remove that much material from the head. We're planning to CC the chambers next week. Due to the large valve heads I expect the total volume to be equal to or slightly less than stock. And we haven't skimmed the head gasket surface yet.

I've got my camera with me. If I get out of work early enough I'll try and snap a couple of pictures.

-->Slow
Re: Peer pressure and the OHV
Sunday, April 29, 2007 8:23 AM
Alright, its been two days... I apologize, but i am forced to call the dreaded......


PICS OR SHENS!!!




Arrival Blue 04 LS Sport
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Re: Peer pressure and the OHV
Sunday, April 29, 2007 11:42 AM

Yikes! But it's Sunday! I live 45 miles from the machine shop, and I have no idea how many beers my friend has had by now. I can't risk his getting into an accident or getting arrested for DUI before the head's finished.

Seriously, I got there about 6 Friday night (we are supposed to be done at 4, they close at 5) and he was just getting into in his car to go home. I knew he'd had a week from hell so I told him it could wait until Monday. They're just pictures, right? Right???

-->Slow
Re: Peer pressure and the OHV
Sunday, April 29, 2007 5:15 PM
slowolej wrote:Yikes! But it's Sunday!...... They're just pictures, right? Right???




WE DON'T CARE!!! We want our pictures!!!!







Re: Peer pressure and the OHV
Monday, April 30, 2007 2:00 AM
Slow, don't make me bring out the Shens....




Arrival Blue 04 LS Sport
Eco
Turbo
Megasquirt
'Nuff said
Re: Peer pressure and the OHV
Monday, April 30, 2007 9:06 PM
Aw, man.

I've got em! Really!! They're right here on the hard drive. But my old isp changed servers so my login isn't valid, and my new isp doesn't seem to realize that the directions they sent me to ftp in don't work. I'm really hoping I don't have to resort to a cardomain page.

-->Slow

Re: Peer pressure and the OHV
Monday, April 30, 2007 10:05 PM
Ok, I've got 'em.

You can see the bronze 11/32 ID guides and the slight bulge in the chamber wall from machining for intake seats.


Here's the fire ring of the head gasket on the edge of the chamber along with a good view of the point where the intake and exhaust seats almost intersect.



Stock 43mm intake valve on new 46.23mm stainless valve. Exhaust valve is a measly +1mm.


No, you're not seeing things. The margin of that intake valve is huge! I mugh try to find a way to reduce it some or at least back cut it.




Stock valves compared to new. If it's hard to tell the difference, look at the marks from the gasket on the old head and the distance to the valves, then look at the picture of the gasket on the new head above.

I hope to get some CC numbers for the chambers tomorrow.

-->Slow
Re: Peer pressure and the OHV
Monday, April 30, 2007 10:55 PM
Amazing.........cant wait for more updates!






Re: Peer pressure and the OHV
Tuesday, May 01, 2007 2:52 AM
Oh..... my..... farking...... god..... that is by far the awesomest OHV related stuff I've ever seen... I think its safe to say that those are biggest valves you're ever gonna cram into that head, eh?


Does the shop you're working at have a flowbench? I'd kill to see some numbers out of that thing.




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Re: Peer pressure and the OHV
Tuesday, May 01, 2007 6:27 AM
Scarab (Jersey Jay 1.8T) wrote:that is by far the awesomest OHV related stuff I've ever seen... I think its safe to say that those are biggest valves you're ever gonna cram into that head, eh?
I'd definately put it right up there with the LT1 lifter spring conversion. I think there's still room for another mm on the exhasut, but there might be some contact issues on overlap
I can't help but think that the intake valves may be a little shrouded, and it might be more beneficial to use a standard +1mm valve instead, but still open up the chamber to the gasket on both sides...



fortune cookie say:
better a delay than a disaster.
Re: Peer pressure and the OHV
Tuesday, May 01, 2007 6:47 AM
my only question as i'm sitting here staring in awe is this.... this head is for a boosted motor right? So why make the intake valves so big, and not focus more on the exhaust side? The way I'm looking at it, since the air is being forced in by the turbo anyway, wouldn't there be more sense in say a +2mm exhaust valve and a slightly smaller intake (that what is being used, not than stock obviously)? Not to question you, Slow, as its quite obvious you've probably forgotten more about engines than I know, but I was just wondering what the science is behind your particular selections.




Arrival Blue 04 LS Sport
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Re: Peer pressure and the OHV
Tuesday, May 01, 2007 8:11 AM
^^^^^^^^

because its cool!


1998 Chevrolet Cavalier
5-spd


Re: Peer pressure and the OHV
Tuesday, May 01, 2007 10:24 AM
Quote:

because its cool!

Damn right!

Quote:

I was just wondering what the science is behind your particular selections.


Parts cost and availability are a big part of it. The price for the parts in this job so far are less than using 1mm OS valves with 7mm stems. By using 11/32" stems I can use standard smallblock Chevy spring retainers which I already have here, and I think I'm going to get some springs for short money, too. I could have saved some cash by using 1.60" exhaust valves but that would have put me in a real bind for an intake valve. I've spent many hours looking through books and the only viable option for reasonable price was the big block chevy valve. I spent a lot of time looking at ports and thinking about this before I decided that the exhaust port is extremely short and likely presents less restriction to flow than the intake side. I expect porting in the exhaust to show good flow with only a slightly larger valve. The trick is going to be getting the exhaust gasses to turn the corner and I might play games with ceramic coatings in 1/2 of the port to see what happens there. The shrouding on the intake side might be more of an issue with an N/A engine. We'll see.

I am hoping to bring this head and a stock counterpart to someone with a flow bench after we're done here.

-->Slow
Re: Peer pressure and the OHV
Wednesday, May 02, 2007 4:38 AM
I didn't believe the information in the OHV buildup article, so I've just measured a 2.2 rod big end width. It's 1.032" which means the smallblock rods are too narrow at .940" and the 60 deg V6 rods are worse at .8"something. So I'm either spending cash on aftermarkets or possibly using OE rods from a straight 6.

If I could find 2 people interested in 5.7" rods there would be about a $100 savings by pooling funds and buying 2 sets of Eagle 6 cyl rods. Too bad everyone with an OHV is cheap like me.

-->Slow
Re: Peer pressure and the OHV
Wednesday, May 02, 2007 11:09 AM
^ lol yea I decided to not be frugal and went ahead and got the eagle rods......and I'm ordering my crank scraper and windage tray assembly today. I can wait to see what #'s ur head put down. Keep it coming now I have something fun to read when I get home from work.








Re: Peer pressure and the OHV
Wednesday, May 02, 2007 2:11 PM
JUCNBST wrote:^ lol yea I decided to not be frugal and went ahead and got the eagle rods......and I'm ordering my crank scraper and windage tray assembly today. I can wait to see what #'s ur head put down. Keep it coming now I have something fun to read when I get home from work.
I tried emailing the crank scraper guy, but never got a reply, and there's no purchasing/payment function on the website...

Slow, have you seen the Somender Singh groove design concept? I want to see someone try it on an LN2, and it looks like you may very well be done before me or Jack.



fortune cookie say:
better a delay than a disaster.

Re: Peer pressure and the OHV
Wednesday, May 02, 2007 2:20 PM
You have to email them your engine and year for the order and they you can do it over the phone or via paypal. Send an email to sales@crank-scrapers.com Or you can call
them @ 727-808-8602. Just ask for Kevin. I sent them my eagle rods a while back so they have a template for the scraper to work with them as well just let them know if your running them or the stock.........

Hope this helps.






Re: Peer pressure and the OHV
Wednesday, May 02, 2007 2:31 PM
Slow, what are the details on the 6 cyl rods? I might be interested depending on how much modification is necessary, if any... 5.7" is the stock rod length or no? I don't seem to have that spec in any of my OHV files.




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Turbo
Megasquirt
'Nuff said
Re: Peer pressure and the OHV
Wednesday, May 02, 2007 4:02 PM
OHV notec wrote: I can't help but think that the intake valves may be a little shrouded, and it might be more beneficial to use a standard +1mm valve instead, but still open up the chamber to the gasket on both sides...


Don't forget that the heads afre canted valve design, just like a BBC. The intake valve is angled towards the center of the chamber and unshrouds itself as the lift increases.

Scarab (Jersy Jay 1.8T) wrote:... 5.7" is the stock rod length or no?


5.589" actually. The Eagle Rods for the 2.2OHV are 5.590".





Re: Peer pressure and the OHV
Wednesday, May 02, 2007 5:46 PM
Nominal dimensions for Eagle crs5700sw3d rods for inline six are 5.7" long,2.00 rod brg dia, 1.029" big end width, .927 pin dia, and 680 gram weight. I don't think they're worth buying unless you're planning to get custom pistons. And I've heard the inline six rods are actually fairly strong. I'm going to be asking some of the "old timers" to tell me stories about building power with the I6 back in the day.

Quote:

Slow, have you seen the Somender Singh groove design concept? I want to see someone try it on an LN2, and it looks like you may very well be done before me or Jack.


Ehh?? No, that's a new one. I guess I'll be using Google tonight.

-->Slow
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