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  #71  
Old 06-09-2010, 06:36 PM
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ccracin ccracin is offline
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Originally Posted by GregWeld View Post
Vic ---

I know people mean well... and usually bite my tongue - but bad info is not what this forum is all about. And that was just plain BS info wise. Can't have people come on here and put up info that might be taken as "gospel" by some less knowledgeable person. We have to remember that LOTS of people read this stuff -- and many aren't members even... Any given day - there are usually more people reading than there are members.... So you (not you personally) post up crap info and people go way either thinking that Lat G is a bunch of bozos and not worth joining -- or newbies go away with some garbage info stuck in their sweet little heads.


Almost ANY of the real gearheads on here - would tell you (confirm) that Pauls timing statement is just BS. I don't know where he got that - I've certainly NEVER heard a rule like that - EVER... and I've been doing this stuff for going on 40 years now... lots of motors - lots of races - lots of car builds... I'm sure he meant well - and probably believes his statement - but he shouldn't because it's not correct.

Well said Greg. I agree that piece of info is as far from the truth as it can be! Go to any Dirt Late Model race and you will see 14:1 motors locked out at 30+ degrees. An engine is an assembly of systems that need to work correctly for the whole to work. One problem can be caused directly by another. A thorough walk through of one thing at a time verifying each area is correct no matter how insignificant it may seem is sometimes the only way to solve an issue you have been working on for a long time. When frustration sets in you start going blind. (Figuratively) Step back and start at the beginning. I don't car how many starters you bought, get another one. Start over with the alignment and go from there. Breathe and take it one step at a time, but do it with a different starter. Good luck.
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  #72  
Old 06-09-2010, 09:03 PM
camaro1969 camaro1969 is offline
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yeah, but i need a mentor, too young and lack of experience makes me do stupid things lol! so....

im GOING TO BLAKE!! thanks greg, you wrench head

ill call him tomorrow, see what we can do!
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  #73  
Old 06-10-2010, 09:21 AM
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Good idea if you can.... because it could save you a motor - or some other major costly headache.

Having just run a new motor on the dyno - and spending some time in the 'cell' as they call the dyno room.. with the operators/engine builders... there was a lot of good discussion about how quickly a good motor can go bad with nothing more than running it too fat (too rich). This knocks the rings out apparently REALLY quickly and they never will seal once they're toasted.

I'm not saying you've done this - or anything like it - it was just an interesting item that I learned. While motors and trannys are generally pretty 'tough' - very small things can cook their goose quite quickly. Maladjusted TV cable on a 700r4 can destroy a tranny in a few blocks... etc.

The motor I just rebuilt (professionally) was a $14,000 'mistake' by the previous builder when he used flat tappet valve springs on a hydraulic roller motor... DOH! Little details like that are fatal.

Ain't old cars fun!?!?!?
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  #74  
Old 06-10-2010, 11:58 AM
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This is odd. I had the exact same problem on my camaro. It was always very bothersome. I narrowed it down to two solutions that may or may not have been the fix, I will never know as I recently sold my car and engine and trans.

1) Retard the timing a bit, and see if it starts up.

2) If #1 does not work, I would look at the flex plate being bent.

I retarded the timing a great deal and it actually started a little easier than normal, with minimal(but still there) grinding. I had concerns the cam was installed wrong. After further review my engine builder flipped around and gave me good cause to believe it was not, take it for what it is worth. I trust my engine builder with my life, so I trust him with my engine's as well.
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  #75  
Old 06-10-2010, 11:39 PM
camaro1969 camaro1969 is offline
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i no longer have the grinding, it was my bendix/pinion that was out of align from being backlashed from a too far advanced dist... anyways i got a new starter, and its since then ive been having this "clicking" noise, so today i removed the starter, and gonna get it tested from the place i bought it, and tell them that i never had the problem with my old starter, which these 2 are like identical!

so i will be trying to make some good progress this weekend, and then once starter issue is dealt with, i am going to take it to blakes, to get a check on why my engine has a fuel pressure of 9psi, and drop 250-300 rpm when i put it in gear! I idle at 900-1000, and drop to 550-700 when put into gear, seems like its gonna stall when i hit the gas.. and it has before too..

itll be the day when my car has NO problems (stopping me from driving the bit*h )
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  #76  
Old 06-13-2010, 07:30 AM
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Originally Posted by GregWeld View Post
Really...... So the 30* locked out timing on my race car engine running 13:1 is just all wrong. Geez.... who knew?

Paul - Not sure where you've gotten this information on base timing but it's just flat incorrect.

Greg,

I'm just getting back to this thread only to find you have thrown me under the bus. Look, 12 degrees base timing is a good setting for a street engine. With his first starter damaged and his vid showing a backfire, it looks like his base timing was too far advanced causing a kickback damaging the starter. Now are you trying to compare a street engine to a race engine that may run down the quarter mile for 10 seconds under full throttle? Here's a real world example........look at the GM performance parts catalog which lists base timing recommendations for all of it's crate engine at 10 degrees. Why do they do this? Because they are want their customers to have a good running engines in their street cars without detonation. Now lets talk about what happens when you advance an engines timing, the spark occurs before the piston reaches TDC on the compression stroke. This works well at higher rpms but can cause problems at lower rpms and if too far advanced, can cause kickback during cranking damaging starters.

Paul
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  #77  
Old 06-13-2010, 09:03 AM
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It really depends on the engine. A factory type engine with a small camshaft is going to deliver higher cranking compression. A bunch of initial timing is going to shorten the life of the starter. I've always run 18-23 degrees of initial but my cam is more than likely much larger than Vic's.
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  #78  
Old 06-13-2010, 09:08 AM
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Quote:
Originally Posted by thedude327 View Post
Base timing being too far advanced will cause a kickback problem that will damage the starters pinion gear/bendix assembly. Get a buddy to sit in the drivers seat with the engine idling in gear and the vacuum line to the distributor removed and plugged and check your base timing. It should be no more than 12 degrees advanced especially if you are running a compression ratio over 10:1 on your engine. Oh and one of your other vids showed a backfire through the carb which is caused by the wrong timing setting.
Good Luck!!
Paul
Paul,

No disrespect here and I won't put words in Greg's mouth. But, when I agreed with Greg my motivation was from the generality of your comment. In general your comment is not accurate. You made no mention of race versus street in the above post. In actuality it really doesn't matter in the context of this thread. Would you want a 13.5:1 Engine locked out at 30deg. on the street maybe not. However after getting the engine running most likely with less base timing and getting it tuned, you could then lock out the timing and it would start without ill effects using a starter rated for the job. Would you want to do it with an off the shelf replacement stock starter, probably not. The point for me is that a lot of people can read these forums and some may not even be members. Not everyone has a firm grasp on all these concepts and they come here to learn and will a lot of times take what they read here as gospel. So making a comment that come off as absolute fact can be mis-leading if in fact the information is not accurate across the board. I truly suspect that Greg's intent was not to trash you and it absolutely was not my intention. It's just to correct the facts being thrown out. I can tell you first hand that I have been around a bunch of engines that start and run perfectly with the exact combination you say is a problem. Can it be a problem, absolutely. But not always. It's all good. The fact that you are willing to try and help is what's most important. In my opinion and the only reason I take the time to respond to your recent post is because I have stuck my size 14 im my mouth plenty and I'm sure I will do it again. I just use this to try and remember when I am posting advice to sure of what I am saying. And if I am wrong and get corrected, I take it as something new learned.



Later,
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  #79  
Old 06-13-2010, 09:11 AM
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Quote:
Originally Posted by thedude327 View Post
Greg,

I'm just getting back to this thread only to find you have thrown me under the bus. Look, 12 degrees base timing is a good setting for a street engine. With his first starter damaged and his vid showing a backfire, it looks like his base timing was too far advanced causing a kickback damaging the starter. Now are you trying to compare a street engine to a race engine that may run down the quarter mile for 10 seconds under full throttle? Here's a real world example........look at the GM performance parts catalog which lists base timing recommendations for all of it's crate engine at 10 degrees. Why do they do this? Because they are want their customers to have a good running engines in their street cars without detonation. Now lets talk about what happens when you advance an engines timing, the spark occurs before the piston reaches TDC on the compression stroke. This works well at higher rpms but can cause problems at lower rpms and if too far advanced, can cause kickback during cranking damaging starters.

Paul

Paul --

Don't take it personally -- but that is just pure nonsense. Just because GM Crate motors use some timing setting doesn't mean that's best in all cases or by default is the "maximum or minimum" timing a guy should use.

Detonation doesn't occur at idle. It occurs under LOAD... and generally from a too far advanced TOTAL timing setting. That is not controlled by the INITIAL timing of an engine - but rather - is controlled by the advance CURVE and the TOTAL timing of the distributor.

A typical MSD distributor has multiple choices of controlling the total timing and the curve. They include in their distributors (when new) stop bushings - and several spring choices - allowing the user to customize his distributor curve etc to match the engine. For an example - if a guy changes out the stop bushing to the 18* version - his distributor would have a total advance capability of 18*. So if you wanted to have 36* total advance - then the initial would automatically begin at 18*.

Timing is totally CUSTOM and depends on a great deal of factors. Head choice - cam choice - compression (really should be called cylinder pressure) - gas quality...

I agree with you that too much timing will cause problems - just as too little will do. But the oldest "rule" in the book when it comes to timing - is to run as much as possible without causing detonation. What that number is - is completely variable. And it sounds to me that you're used to only running stock distributors with stock curves in them. If that's the case - then yes - 12* would be "the max" a guy could live with because when you're advancing the initial - you're also advancing the total... and in a SBC after 36* or 38* you're in trouble..But again - that would depend entirely on what the distributor is set up for. If it has 24* of advance built in - then the max initial timing you'd want to set would be @ 12* and so on. Frankly - the best way to set timing is to set it at total - and let the initial fall where it will... and adjust your idle etc to work there. If the initial is too low or too high - then you have to modify the distributor to get you to what is needed by the application.

My new 408 has a total of 32* - it ran stronger and made more TQ at 32* than it produced at 34* or 36*. The MSD in it has the 18* stop bushing (giving it 14* of initial) - one light blue and one light silver spring for the curve control.

My brother in laws blown 355 with iron heads and blower cam - runs 30* of initial timing and goes all the way to 32* total. It's street driven and fires and runs flawlessly.

Just FYI -- back in the day (I crewed for McCulloch and Whipple) we ran 70* of timing in the nitro hemis of the day.

My only point is that when someone asks "what's the best timing"? The response would be "that depends"...
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  #80  
Old 06-13-2010, 09:29 AM
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Quote:
Originally Posted by Vegas69 View Post
It really depends on the engine. A factory type engine with a small camshaft is going to deliver higher cranking compression. A bunch of initial timing is going to shorten the life of the starter. I've always run 18-23 degrees of initial but my cam is more than likely much larger than Vic's.
Oh nice one Todd.... here we go with the "mine is bigger than yours"....
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