SuzukiSavage.com - What's the effect of the cam issue?

Lazy Old Rider

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Re: What's the effect of the cam issue?
Reply #15 - 02/13/08 at 10:01:50

viper wrote on 02/12/08 at 17:50:06:

Yes the exhaust valve starts to open just before BDC after the power stroke as the piston pass's BDC the ramp of the lobes profile opens the valve to its full open pos. while the piston is comening up as the piston nears TDC the lobe profile starts to allow the valve to start closing keeping it with enough clearance from piston as not to have contact. Many cams have profiles which will keep the exhaust valve open ever so slight past TDC of the exhaust stroke an allow the intake valve to start to open This allows air fule mix to pass out the exhaust .This is a scavaging to clear cylinder of exhaust gas's and start the intake stroke. Many do not realize there is a very low vacume at the exhaust port as the valve nears closing but this relies on the cam lobe profiles. This is one reason it is very importain to address valve adjustments with the correct engine temp and the correct clearance You must sure make sure you are at TDC at the end of the compression stroke.
It's late Iv'e said enough
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Thanks much clearer, probably gives higher compression, less stroke and more revs as I think about it

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T Mack 1 - FSO Serious Thumper Alliance Member Offline sold 2001 LS650 for a 1986 XLH1100 Posts: 2919 Emmaus,Pa Gender:	Re: What's the effect of the cam issue? Reply #16 - 02/13/08 at 10:43:07 Reminder to all, many pistons are hybrid. The engine/head combo are "interference" but the pistons face has grooves cut into them to create non-interference or valve clearence (see below). The LS650 piston has a flat face. :'(
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smokin_blue

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Re: What's the effect of the cam issue?
Reply #17 - 02/14/08 at 03:19:21

verslagen1 wrote on 02/13/08 at 09:06:00:

How can all these engine mfgrs have "non-interference" designs when the savage doesn't, especially concidering it low compression ratio?

Every car that I've every owned has had the issue. Can anyone confirm this design feature?

V-man, I can confirm existance of the non-interferance engine. The discussion and quote earlier in the thread is correct. Many engines are "interferance engines" that is if the valves are open and the piston comes up (with out the valves moving) they go SMACK. Hello bent or broken valves. Engines such as the B-Series mazada which has the description of non-interferance head is correct. The valves can be wide open and the piston come up and not touch a valve. It has to do with how much head volume do you have and how you shape it/ use it. My '86 Mazda B2000 (the engine described by Keithert) does just that. Right after a very experienced high end mechanic and previous owner of my Mazda told me don't worry about the timing belt at 60K they go for 90k all the time.....mine stripped while starting it at a rest stop 120miles from home. After spining the engine many times until I diagonosed what had happend I called home and my dad and a buddy brought up a flat bed trailer and hauled me home. Per the manual (and quote by Kiethert) I paid $32 for an OEM timing belt, set the cam timing, installed and was good to go. If I had may sister's Nissan at the time it would have been a $600-$800 job. (as that one would have gone SMACK!)

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azjay

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Re: What's the effect of the cam issue?
Reply #18 - 02/14/08 at 05:56:50

valve angles, total lift, combustion chamber shape, etc. determine interference or not. the ford 2.3l ohc is a non-interference design, as the is the 2.0l. if the valves are open at STOCK lift, the pistons will not contact them, while rotating the crank and not the cam. if you mill the head, change the cam for more lift, you change the rules. the savage IS an interference design, if the cam chain pops, internal parts will run into each other.

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Rockin_John

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Re: What's the effect of the cam issue?
Reply #19 - 02/14/08 at 13:30:59

azjay wrote on 02/14/08 at 05:56:50:

valve angles, total lift, combustion chamber shape, etc. determine interference or not. the ford 2.3l ohc is a non-interference design, as the is the 2.0l. if the valves are open at STOCK lift, the pistons will not contact them, while rotating the crank and not the cam. if you mill the head, change the cam for more lift, you change the rules. the savage IS an interference design, if the cam chain pops, internal parts will run into each other.

Not much of a Ford fan after about 1959... But I did have the opportunity to do a timing belt on a friend's Pinto with the 2.3L as a teen back in the 70s. I was pretty sure it was a "non-interference" design since the belt let go on the Pinto when the engine was revved up real tight. Cheesy

As I recall, it only took about an hour or less to change the belt on those.

I guess over a few decades that little 2.3L reached almost legendary status. I recall that they got 212HP out of it in the "Turbo T-Bird." And there were several spec racing classes in both autos and boats based on the little beast.

As I previously mentioned: the Chrysler 2.0L and 2.3L (made by Mitsubishi IIRC) of later years would go: Bang! Clank, clank, clank... if you let the belt give way on them. Very not-cool. Undecided

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azjay

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Re: What's the effect of the cam issue?
Reply #20 - 02/14/08 at 17:31:35

[quote author=6459555D5F58697C595E58360 link=1202825033/15#19 date=1203024659

I guess over a few decades that little 2.3L reached almost legendary status. I recall that they got 212HP out of it in the "Turbo T-Bird." And there were several spec racing classes in both autos and boats based on the little beast.
[/quote]

that is true, my dad raced in the 2.5l modified hydro class. (he and esslinger were on a fisrt name basis). running straight alcohol, he made 300+ hp, somewhere over 320 hp it starts to break cylinder walls Shocked

the little chryslers have a good following too.

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verslagen1 YaBB Moderator ModSquad Offline Where there's a will, I want to be in it. Posts: 28886 L.A. California Gender:	Re: What's the effect of the cam issue? Reply #21 - 02/14/08 at 18:12:30 Dam, learned something new. Thanks guys.
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