W2 Mopar inspection w/RAMM

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Here's a quote from you mentor "Tuner" about timing and chamber and swirl port design.


"This spark advance requirement is very similar to the mid-late 80’s and early 90’s SBC heads (prior to the Vortec) with the spiral ramp in the intake valve pocket. There is a 318-360 LA Mopar head with the same port scheme. Both the Chevy and the Mopar head are allergic to more than about 25° total. Just like ‘modern’ fast-burn engines, no matter how high octane the fuel, advancing the timing more than a few degrees on a stock 235 only makes it overheat, even if it doesn’t spark knock.

Like any other engine, fast burn or not, the 235’s and the swirl port Chevy and Mopar, when the valve timing is adjusted to a more sporty profile, they like more initial timing, but they don’t like any more total."

And here on the Chevy swirl port TBI heads

"That intake port and head is one of the slickest things for torque and mileage since sliced bread. It will make good power with moderate cams like those used for street or short-track racing. The reason they get such a bad rap is they are absolutely, positively, no doubt at all, allergic to more than about 25 degrees of total timing, no matter what octane of fuel is used. Pump gas, 24 degrees, C16, 25 degrees, it won't matter. At "normal" 36 degrees they will knock and overheat."

yellow rose said:
It doesn’t. Swirl, twirl, tumble, bumble all that are CAFE emissions stuff. Any time you make the air column change directions you lose velocity. That is a power killer.

Unless you are trying to light cats on a cold engine fire up or think this type of thing saves the world, it’s useless.

Edit: plug location and rod/stroke ratio are the two biggest factors in total timing. Swirl, twirl and all that and quench doesn’t affect timing very much if at all.
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Hysteric said:
Here's a quote from you mentor "Tuner" about timing and chamber and swirl port design.


"This spark advance requirement is very similar to the mid-late 80’s and early 90’s SBC heads (prior to the Vortec) with the spiral ramp in the intake valve pocket. There is a 318-360 LA Mopar head with the same port scheme. Both the Chevy and the Mopar head are allergic to more than about 25° total. Just like ‘modern’ fast-burn engines, no matter how high octane the fuel, advancing the timing more than a few degrees on a stock 235 only makes it overheat, even if it doesn’t spark knock.

Like any other engine, fast burn or not, the 235’s and the swirl port Chevy and Mopar, when the valve timing is adjusted to a more sporty profile, they like more initial timing, but they don’t like any more total."

And here on the Chevy swirl port TBI heads

"That intake port and head is one of the slickest things for torque and mileage since sliced bread. It will make good power with moderate cams like those used for street or short-track racing. The reason they get such a bad rap is they are absolutely, positively, no doubt at all, allergic to more than about 25 degrees of total timing, no matter what octane of fuel is used. Pump gas, 24 degrees, C16, 25 degrees, it won't matter. At "normal" 36 degrees they will knock and overheat."
Click to expand...


Yep, and I disagree with that. I have never seen any SBM or chevy or Ford with conventional OE chamber geometry run timing that low. Unless the guy runs 3 ranges too hot a plug. That is a tuning tool used by some to rub their dicks and make people think they are cool because they run under 30 total. Seen it on the dyno on customers engine. Sent it home wit th e plug in it I wanted, and it came back in the car with a different plug. It had been tuned by a guru.

It was down on power and wouldn’t run over 28 total. Liked less. I’m thinking WTF??? It took 34 when it left here. So he pulled a plug and you could have welded with the damn thing.

So I went and pulled his build sheets and his invoice and sure enough, he signed off on not touching the tune up until it came back in, including the plugs.

BTW, it came in because he was beating the **** out of the bearings. No doubt, his use of glow plugs was an issue, and like a dog returning to his own vomit, he went back to them because his guru said that 34 is too much total.

Put the correct plugs back in it, and it went right back to the HP it left with and 34 total.

So I haven’t seen these super fast OE chambers.
 
No offence, but i'll take Tuners opinion over yours any day.

Here's another thread about timing.

Ford Windsor 408's HP Plateaus @ 5,600 - Don Terrill’s Speed-Talk

And yes i was the guy who asked Tuner if it was lean.

yellow rose said:
Yep, and I disagree with that. I have never seen any SBM or chevy or Ford with conventional OE chamber geometry run timing that low. Unless the guy runs 3 ranges too hot a plug. That is a tuning tool used by some to rub their dicks and make people think they are cool because they run under 30 total. Seen it on the dyno on customers engine. Sent it home wit th e plug in it I wanted, and it came back in the car with a different plug. It had been tuned by a guru.

It was down on power and wouldn’t run over 28 total. Liked less. I’m thinking WTF??? It took 34 when it left here. So he pulled a plug and you could have welded with the damn thing.

So I went and pulled his build sheets and his invoice and sure enough, he signed off on not touching the tune up until it came back in, including the plugs.

BTW, it came in because he was beating the **** out of the bearings. No doubt, his use of glow plugs was an issue, and like a dog returning to his own vomit, he went back to them because his guru said that 34 is too much total.

Put the correct plugs back in it, and it went right back to the HP it left with and 34 total.

So I haven’t seen these super fast OE chambers.
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Hysteric said:
No offence, but i'll take Tuners opinion over yours any day.

Here's another thread about timing.

Ford Windsor 408's HP Plateaus @ 5,600 - Don Terrill’s Speed-Talk

And yes i was the guy who asked Tuner if it was lean.
Click to expand...


I’m not offended. I’m not stupid and I didn’t just crawl out of the gutter either. I may have a mentor but he doesn’t think for me.

I have plenty of years of real world expert hat tells me all that swirl and crap is just that...bullshit. It’s not for making power.

Will it help a junk SBC chamber? Maybe. With a horrible plug location? Probably. That’s a crutch not a fix.

I’ll say it again...show me ANY OE based chamber geometry and I’ll tell you it need 34 or more or something else is wrong, and no amount of mixture motion quench or anything else will cure that.
 
The reason it wanted that much timing was because it was lean. You must be tired as I'm sure its late over there so you must have missed this:

"If this is the head and combustion chamber the engine has, I would be surprised it is happy with 36 degrees total. I have tuned a few SBF with this head and similar heads in the last 10 years or so that were happy with 30 or less .... 26. Too much timing, even if it doesn't knock, will make the engine feel like the brakes are dragging or the car is towing a parachute."

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Hysteric said:
The reason it wanted that much timing was because it was lean. You must be tired as I'm sure its late over there so you must have missed this:

"If this is the head and combustion chamber the engine has, I would be surprised it is happy with 36 degrees total. I have tuned a few SBF with this head and similar heads in the last 10 years or so that were happy with 30 or less .... 26. Too much timing, even if it doesn't knock, will make the engine feel like the brakes are dragging or the car is towing a parachute."

View attachment 1715676948
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I already stated that I have seen two SBF's with AFR heads that made best power @ 24 total. Both were high compression examples and didn't like more than 24 probably because they were running into detonation territory. You're above statement is no mystery at all either--when the timing is too advanced the engine will feel like the brakes are on because-----You are trying to light the fire while the pistons are starting the compression cycle. In other words the engine is performing way too much NEGATIVE WORK. Not sure what you are trying to say between this thread and the other. Wish you would spit it out so we can address your concerns and move on. J.Rob
 
Hysteric said:
The reason it wanted that much timing was because it was lean. You must be tired as I'm sure its late over there so you must have missed this:

"If this is the head and combustion chamber the engine has, I would be surprised it is happy with 36 degrees total. I have tuned a few SBF with this head and similar heads in the last 10 years or so that were happy with 30 or less .... 26. Too much timing, even if it doesn't knock, will make the engine feel like the brakes are dragging or the car is towing a parachute."

View attachment 1715676948
Click to expand...


So run it lean and pull timing. Got it. Like I said, timing is a NUMBER. I’m not impressed with something that needs 24 total more than something that needs 44 total.

Geezus, you make it sound like anything that needs more than 24 total is junk and won’t run.

EDIT: here is a final thought. I don’t care how “big” or “small” a chamber is. Rod ratio and bore diameter are MUCH a bigger factors in total timing than a small chamber.

Example???? The 340 is the best one. Most has ZERO quench, and big, “slow” chamber and you couldn’t make it rattle at full timing unless you were a full on retard. 34-36 is where they ALWAYS ran and still do, even with “quench”.

BTW, did you notice in your above example, no one asked the OP what plug he was running? I thought about and said piss on it. The hot plug crowd will be all over it. That dude had other issues, and for the life of me, I can’t get your point. Rather than beat around the Bush, spit it out and make your point.
 
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