Here is what I said

And this is what you should have taken away from that

 

SELLC: Please leave this thread. You obviously think there's some magical, mechanical "key" that establishes the relationship of the distributor to the cam. In a computer-controlled HEI engine, there is NOT.

You CAN put the distributor in/on any tooth. There is a way you establish base after that -- having nothing to do with where you stabbed it.

Also, nothing you've communicated in this thread conveys that you have specific knowledge of how electronic timing can/should be changed -- with relation to TDC (the crankshaft) just because you change the timing of cam events through mechanical rotation.

When combustion happens, both valves are closed anyway. Because the engine is a "dynamic air wave machine", that rotation of the cam raises/lowers where power is maximized. Scavenging and reversion come into play.

Timing changes more dynamically on a computer controlled engine because the user has the ability to control/maximize spark for any rpm/load. That magical gear/tooth relationship YOU think exists does not. The base timing on an ECM-controlled car does not change and I strongly suspect it doesn't on a variable valve motor either.

If you were a choice of mechanic, I would keep driving to the next shop. I apologize if this sits wrong, but you don't have the ability to explain things in a way that is actually helpful. I believe (as explained above) that you have some holes in your knowledge.

Of course, we all do. That's what I've posted in this forum on/off for years. It's a good place to learn. If you WANT to better understand how ECM "base" timing is established...and why is has NOTHING to do with which tooth the dizzy/cam are connected on, feel free to start a thread on it.

 

In the instance that said car must not have overheated before the camshaft, and the fact that OP clearly states that the engine has never been run out and he just assumed +4 degrees of advanced cam timing, YES.

This is however, assuming a precursory inspection of the cooling system has been done, which according to OP, the radiator has already been upgraded and now he is considering upgrading the fan.

He might not have needed a new radiator or a fan if the vehicle wasn't running hotter under a load.

As a professional, certified mechanic, I am saying that the engine is not set up properly and lacks any mathematical certainty when it comes to the timing. That is a "root" issue that any professional will insist be rectified before fooling around elsewhere.

This is not a "factory" or "OE" application.. You can not just assume something as important as timing, nor can you rely on "factory" settings. As it stands, in Michigan, you do not have to be certified to change oil, tires, or perform modifications on vehicles intended for "off road" performance use. There is a good reason for this.

 

That's all I need to hear. Enjoy your overheating vehicle!

Ill be sure to point and laugh when your on the side of the road and everyone else is cruising. Since this will be my last post to this thread per the OP, let me also say this... You suffer from what many professionals call "identity crisis". Your low tech and low dollar engine and components are not designed to operate as both a "race car" and a "street car" and I cant tell you how many times I have seen this.

You lack the $$$ to do what you really want. But blame it on me if it makes everyone feel better.

 

Holy cow pal. This isn't even fun anymore. There are so many problems with what you said that it feels like we are going backwards. Anyway good luck w your career. Try to gravitate towards suspension and brakes.

 

You are right... This isn't even any fun anymore. I got better things to do, like go drive my Corvette because my career is so generous to afford such a luxury, without overheating might I add.



According to OP each gear last 2 seconds before it runs out of grunt! LOL! That must mean he runs the 1/4 mile at 8 seconds and blows thru the traps at max RPM in top gear.

You guys... Grow up.

 

I have the B4P option so I have both the stock puller/pusher.

I have 5.7" rods, stiffer springs, and an .030" overbore 4-bolt block. With the overall "torque" build theme, I selected parts geared toward that. The cam is a single-pattern. It was either 214 or 216 duration. I can't find the car at this time -- but I do see where I'd posted that it's got an 111LSA. I have a Champion dual row radiator. It has a hi-flo water pump though the brand escapes me this minute. (PRD or something?)

When a friend helped me design the cam, we used EA. The caviat was that I wasn't sure whether it would end up under a super-hogged TPI or an HSR. The TPI dictated a straight-up installation but the HSR dictated 4-deg advance. I thought it likely I would swap to the HSR (and/or that I would like ANY config favoring bottom-end torque).

On 80 of a 100 drives, I might be prone to a short stab of the throttle mostly within the speed limits. How fast you get there is often governed by torque....since it might not provide longer opportunity to hit redline. On 1-2 of 100 drives, I might push rpms high enough to wonder how it might react if I reinstalled the cam in the neutral position (or even retarded if Bullet did ground 4-deg advance in the cam).

If I'm really +8, then I'd have shifted power down as much as 1000 rpms. IIRC, I'm over 350rwtq by 2500 rpm. It might only be 25lbs less at 2k rpms. Peak is between 3500-4k rpms. It's a fun street car (with a ZF6) that doesn't need shifting to push local laws. IOW, a short burst in any lower gear pushes most conservative limits.

When I timed it, I used BLMs, INT, and even O2 sensor feedback to optimize power for any given rpm/load in the timing table. I guess part of the question should be whether that COULD push heat production in the lowest rows?

Again, in the stock bin, there's a big drop in advance for the 600-rpm row where THEY idle. Because mine idles at 800 rpms, I'm running at least 5 deg more advance. On the top end of things, the AFR "like" less timing. Compared to stock, I'm running 4-5 degrees LESS total timing at 5k rpms.

Again, the higher timing was left on the 800 rpm row because I liked the smoother transition off-idle. Less timing might lower idle temps but I'd rather keep it and find another way to eliminate heat creep.

As for MY term overheating, that hasn't actually happened. I just do whatever it takes to make sure temps don't exceed 230. Really, I'm shooting for 200 as the highest temp...even in traffic with the A/C on. That's why I went to a bigger radiator and might ALSO need a fan with enough static pressure performance to pull through it's extra width.

(And, combat the thinner cylinder walls, stiffer springs, hotter timing, cam advance, and/or whatever else you might think contributes to heat).

 

We don't know that it doesn't. We do however have a new understanding of the present state of modern auto repair talent.

 

You know...I never considered posting a picture of myself after being butt-hurt. That's a new approach, though closely aligned with the visions of self-grandeur displayed from the start of this thread!

 

Load up the parts cannon boys!



Let's say this together kids.... "Timing is relative". Keep saying it over and over now!

 

lolol ... now that is funny.

 

idk what those dudes said cause I don't read post of people who get into a pissing match, it's a waste of time. But I did state overbore/thinner walls put more heat into the coolant, not only are they thinner to allow easier heat transfer it's an increase in surface area to absorb more heat, that the coolant picks up.

And stronger/stiffer or thicker/more material springs make more heat that the oil absorbs and that's less heat the oil absorbs from other parts. Every time you compress those 16 springs work is done, larger wire springs or larger lift cams and more work is done and work creates heat. Sure roller rockers will reduce some of that heat, some say 20deg but I monitored a recent stamped to roller swap and it only reduced ave oil temps 5-15 deg depending on the use. Turn an engine over by hand with the rockers off, then with.

There I've explained my comments a bit more and take it or leave it I'm not gonna go on for 5 pages.

 

Great cartoon!

To be fair, I know you tried to help. My issue is you spent several pages/posts arguing credentials/ability without giving specifics of ANY relationship between electronic and cam timing. You can't just say there is a relationship unless you explain how/why.

For example, someone could talk about why less timing is used at higher loads/rpms than lower ones. That's because it would be possible for someone to assume electronic timing is based on the lead time electricity needs to generate the spark -- in relation to the movement of the piston up the cylinder. (This is just an example to illustrate my point).

I might conclude that advancing the cam creates more cylinder pressure and, therefore, might lower the requirement for spark intensity...or even advance. IOW, maybe it would benefit to use a cooler plug and run a big less (or more advance). YOU GOTTA SAY WHY.

Other things like rod length -- as it relates to cylinder side load have specifics of their correlation. I've never had trouble understanding who explains anything clearly.

As for the relationship of the distributor to the cam -- in my 89 HEI/ECM controlled engine, you can insert the distributor as you see fit. Once installed, you use a timing light to set the advance of the dizzy contact (for cyl #1) a few degrees before TDC. Once that's done, you program the ECM (if needed) to provide it with the base (mechanical) amount of electronic lead for #1 spark. From there, there is a reference wire running from the distributor to the ECM that "tells" the ECM where the rotor is at any given point in time. So, there is no mechanical relationship in teeth to the cam. None.

Most of what you have been talking about sounds like someone covering "old-school" timing (and advance) in a mechanical distributor on a carbureted, non-computer-controlled engine. If you don't see why, I won't try to explain it.

As for what was done to my engine, I had the short-block builder degree the cam and check for clearances. After he was done, I finished the rest and installed the motor. It wasn't until a couple of months later that I asked him how he timed it. (I asked because I remember telling him I might choose to go +4 advanced. I considered this because of the way I drive, where I wanted power, the recommendation of Bullet cams, etc....). The builder couldn't remember. I called Bullet (at that time) and asked what my cam specs were -- because I'd moved and misplaced the cam card. They retain them on file. After explaining my concern their desk-jockey said the cam had +4 advance "built-in". To me, that means in relationship to an arbitrary (though likely industry-accepted) relationship of the lobes center to "zero". In short, I also asked how big of a problem it might be if ANOTHER 4 degrees were added -- if it were installed advanced on the timing set. This guy...like others I'd talked to at Bullet, touted how great advance is in a street car...and how it's common in track cars too. He advised me to leave it as-is unless I was unhappy with performance -- which I'm not.

Don't throw creeping heat into the conversation of performance either. That's not what I mean. And, if you want to be argumentative w/o providing concrete details, I don't see how readers (or I) would benefit.

Fair enough?

 

Thanks man. I understood your meaning when I posted the sentence you quoted. I think you made a good point in explaining why OTHER things besides timing were more likely to have increase the running/idle temps in my 383 [over an OEM L98].

 

Well thanks, I can't take credit for it, but it feels appropriate.

I'm just going to say I read this and I am not going to even ask why.

Your HEI distributor connects to a gear on the camshaft that is also connected to the crankshaft. That said, you set timing by getting the cam sprockets aligned with the engine at TDC, then as you say, drop the distributor in pointing to #1 and you seem to think that by modifying the position of the crank pulley +4 that it wont have any correlating effect on proper timing? Well read on and see how!

You really should explain it, because knowing you're using fuel injection means that you have a MAP sensor, which will pick up on your little +4 advancement. In turn, the computer will modify the timing map accordingly, just like an old school distributor will mechanically move the magnets and pickups on an "old school" distributor. A fuel injected computer controlled vehicle is much more resistant to such modifications without proper tuning and proper tuning wont even be possible until you properly set the timing.

If you're happy then why even make a thread?

No, because you're obviously having overheating issues because of over advanced timing commanded by the computer. Why? Because the vacuum is off, why? Because the base cam timing has been modified. If you pull off a vacuum line the computer is going to increase timing and raise the RPM to compensate for the extra air entering the engine.

Vehicles that run hot often have small vacuum leaks if everything in the cooling system checks out, which you said it did.

Doesn't matter if you like the taste of the medicine, it just has to make you better. Right?

 

LOL ... sellc you are so far off on this I actually feel kind of bad for you. Make sure on tuesday you check with some of your co-workers on this issue, or at least do some due dilligence on this matter. Your making a fool out of yourself and you don't even know it. There is a veratiable avalanche of evidence to the contrary of your thesis. At the minimum you should be able to explain in a coherent manner why you think what you think. So far you have been unable to do that. The reason is because what your saying is total nonsense, which is always impossible to explain. I read some of your other posts and you seem like your capable of understanding this issue as it relates to timing, but until you check your ego, your not going to get it. You seriously might as well be walking around wearing a clown suit, what your saying is really that absurd.

 

I understand this stuff is over your heads.

 

People ask questions then complain when they get answers. Then you always have the straggling troll who wants to jump on the train.

Now you have been told by TWO guys "in the profession", one of which (me) is a Master Mechanic.

The old saying, "You can take a horse to water" applies here... And this is the thanks I get for trying to "help". Yeah, I know... You're only as good as you're needed at the moment and no good deed goes unpunished.

No thanks needed... Honestly.

 

No thanks is deserved. At the very best your advice is misleading. At the worst I could argue you are being intentionally deceptive.

 

So tell us all, oh wise one.... Which came first? The chicken or the egg!?