What's the difference? I know with interference if your timing belt snaps then it's new engine time. I'm pretty sure this is because of the valves going into the pistons. Where do they go on non-interference? Up into the head?
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Originally posted by Tippey764Originally posted by deevergote -
My understanding is that it has mostly to do with head and piston design. Non-interference engines have the valves recessed further in the head or located higher in the dome and they also have deeper valve reliefs in the piston. I don't think that the engine itself is designed differently in terms of function, its just a difference in engineering that focuses on specifications that will not result in valve/piston impact in the event of desynchronization.
Just a theory, but I would suspect non-interference engines tend to be lower compression than interference engines. I would also suspect that they have fewer valves than interference engines. It also would not surprise me if the cylinder displacement tends to be larger, making more room for space in the head while maintaning compression ratios. I would further suspect that interference engines have larger cams and produce significantly more power, liter for liter, versus a non-interference engine. -
Really nothing other then clearance.
It is not true that the closer your piston is to your head is the only way to raise compression.Your rod,stroke and bore are the main factors.
Hope this helps,either way your running a Honda so if your timing is off or your belt breaks,buy a head or have it re-worked.Comment
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i had a timing belt break once on my f22a1 and i put a new belt on and had 210-220 compression all the way around. my guess is that the belt snapped with the valves all closed or almost all closed, i was not aware that the belt had broken, and this was while trying to start the car. dont buy ebay timing belts
not sure how often that happens with interferance engines_
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This... to an extent, most non interference engines I have rebuilt have no cutouts in the tops of the pistons. Otherwise you are correct.Originally posted by TheFirstNutZo View Post
No. No. Commonly. No.Originally posted by TheFirstNutZo View Post
The two different engines can both have the same CR but non interference tend to have a much longer stroke to create that same CR. They also usually do not have a high redline. They have the same ammount of valves. The non interference L61 in my Cobalt has 16 valves just like the f22(interference engine). The only engine I know that disproves that is the Yamaha 5 valve Interference v6 engine. Displacement is usually slightly larger but as I said before it is due to stroke, not bore. Liter for liter with the same mods they can and usually will make the same amount of power.Call me Travis.
2006 Cobalt LS/SC ~ "Burt the Bloody Bumble Bee"
1992 Accord LX ~ "Smoothie"
1991 CRX Si ~ Hellion
1989 GMC S15 ~ Oldie
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Cool, thanks for the corrections
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Not true. The H22 is non-interference out of VTEC and its compression is decidedly higher than an F22 which is interference all the time.Originally posted by TheFirstNutZo View Post
There are a lot of factors that go into it. Like someone already mentioned, rod length, stroke, etc all factor in, as does piston design, head design and valve lift and duration.Comment
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Not a problem, I am a jack of all trades and master of none.Originally posted by TheFirstNutZo View PostCool, thanks for the corrections
Call me Travis.
2006 Cobalt LS/SC ~ "Burt the Bloody Bumble Bee"
1992 Accord LX ~ "Smoothie"
1991 CRX Si ~ Hellion
1989 GMC S15 ~ Oldie
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Are you sure the H22 is non interference? I had a swapped CE1 in my front yard a couple years ago that jumped timing and bent two valves... I would definately consider that interference...Originally posted by owequitit View Post
Edit, I remember now it didnt bent two valves it chipped a piece out of the face of the valve. Looked like when someone cuts a slice out of a fresh pie... Kinda like Pac Man.Call me Travis.
2006 Cobalt LS/SC ~ "Burt the Bloody Bumble Bee"
1992 Accord LX ~ "Smoothie"
1991 CRX Si ~ Hellion
1989 GMC S15 ~ Oldie
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f22's bend valves, why wouldnt a h22?
at idle it just stop quicker. when you have a manual and keep the vehicle in gear. that crankshaft is spinning till you take it out of gear.
at least with a torque converter, there is "slip".Comment
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Um I am loosing you here. When did transmissions come into the conversation?Originally posted by wed3k View Post
That has nothing to do with engine style...
Also the crankshaft spins whenever the engine is running.Call me Travis.
2006 Cobalt LS/SC ~ "Burt the Bloody Bumble Bee"
1992 Accord LX ~ "Smoothie"
1991 CRX Si ~ Hellion
1989 GMC S15 ~ Oldie
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you really need to do some research on "bump" starting.Comment
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Out of VTEC, the H22 is non-interference. Have done broken timing belts on many that weren't impacted with bent valves because they were not in VTEC when the belt went.Originally posted by Cobalt View Post
If it goes in VTEC, you are hosed.Comment
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The H22 does bend valves. If it is in VTEC. It has a lot less lift and duration out of VTEC, and the valve angles on the H22 are much greater.Originally posted by wed3k View Post
All I know is that I have seen exactly 0 F22 t belt failures that escaped bent valves and numerous H22 failures that didn't bend a thing. Clearly, if the valves weren't bent, there was no piston to valve contact...
And sorry Wes, something that is spinning at somewhere between 13-17 times a second isn't going to stop before contact occurs. It would have to stop within 1 revolution.Comment
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I must be lucky. I have a f22a1. Recently the timing belt broke (it actually just broke about 6 teeth off the belt) at 55mph and it didnt bend any valves. We just replaced the belt and everything was fine. I must have gotten lucky.
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