[Cliff R]

"It did make good power however, 551hp and 550ft lbs peak torque."

Typo on my part, the best pull netted 505hp @ 5100rpms and 551tq.

I'd also add that I tested several different intakes and carburetor on that engine over the course of the day and it took some work to get those numbers. Like many 455 engine builds I've done that particular one wanted a single plane intake and 1" spacer to really show it's colors.

We started with an RPM intake and my Q-jet with no spacer. It fell short on HP production but made great average power. Nearly as I can remember we ended up around 487hp on the best pull with the RPM intake/Q-jet. We finished testing that day with the T-II intake. Topped with a 1" spacer and 850cfm Demon carb we saw the highest HP that day. Without the spacer is made less power everyplace than the RPM intake/Q-jet with no spacer, so another early education for me in making a single plane intake work like it's supposed to.......FWIW.....

[pastry_chef]

Originally Posted by Cliff R

You can research this stuff to the brink of extinction but at some point you've got to close the laptop and head out to the shop and get dirty. It is the ONLY way to find out what works and what doesn't.

That would be true for someone who never built a few cars and engines. Weak attempt to try and discredit.
I've disassembled, designed, reassembled and raced many for decades. Years before this forum even existed. I've spent hundreds of hours at machine shops.
I was lucky one of the best loved to talk and share knowledge, they were a pro shop before 1970. Sometimes we'd go to drop off a part and we'd talk for 4 or 5 hours about everything. Once we left their shop after midnight, in the middle of a work week!. They are close friends with another local racing legend who held many NHRA records. I've heard hours of "secrets" they shared about things he did in his engines. Some of it pretty wild.

Steve has told me he told you this in many personal emails but you don't get it. I get that,, it is hard to admit I'm not some 14 year kid with only Google.

Other research, knowledge and tools I've accumulated mostly over the last 15 years only serves to supplement and expand the previous base. Some of these tools cannot be acquired today, are used by top heavy hitters in motorsports. One of my mentors with over 35 NHRA records holds huge value in, this man I've learned more from than any other on the planet.
I'm also close to Rick Jones, Mike Jones brother. He may be second as a internet teacher.
I could go on and on further but this is enough.
I don't expect this will clear your confusion and ego problem.

[Cliff R]

Ego problem, were you looking in the mirror when you typed that?....

So I'm confused and have an ego problem. Tread softly in that area, personal comments/attacks are not permitted here, but you are correct about the confused part. I have BAD cases of CRS these days and even worse cases of DGS. Probably doesn't help that I've had over 13,000 work orders completed since going full time in these business and keeping good records. I talk to so many people it's all a blur at this point and moments of confusion are a daily and sometimes even an hourly occurrence!

I also did some hanging-out with local "gurus" and legends way back when I still squatted to pee. Two of them in particular were very successful racers, engine builders and both ran their own speed shops for quite a few years. I learned a lot from them and still pass some of it on today but in this environment NO ONE wants to hear that a 3/4" wide stock type silent Morse chain is stronger than the roller they just bought for 6 times the price, constant tooth contact, absorbs some harmonics, less spark scatter and will turn out a few more ponies on the dyno and just a fuzz-nut quicker in ET and MPH at the track.

Tucked away deep in the memory banks I have good info and quite a few other things to pass on, but one has to be selective these days as there will ALWAYS be a few folks who get their panties all wadded up if/when you badmouth a part they have vested a lot of funds into and seem to have good luck with it.

Anyhow, Steve says good things about you. I'm just waiting to see a dyno chart from the Pontiac engine in your car and a couple of time slips to see how well it works........

[Tom Vaught]

Originally Posted by Cliff R

NO ONE wants to hear that a 3/4" wide stock type silent Morse chain is stronger than the roller they just bought for 6 times the price, constant tooth contact, absorbs some harmonics, less spark scatter and will turn out a few more ponies on the dyno and just a fuzz-nut quicker in ET and MPH at the track.

SHUSHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH

There you go giving away those OEM secrets again.

The Pontiac 4 cylinder chain was one of the best designs to drive a camshaft ever produced. ATIAF (And That Is A Fact).

Tom V.

[Cliff R]

I know Tom. One of my mentors used the plastic coated 3/4" wide variety on his racing engines. The guy made great power and ran WAY under the index back in the mid-1970's when I knew him.

I wasn't more than a wet-behind-the-ears kid and about chit on the ground the day he pulled the 396 from his 67 Camaro to install the 454. He actually removed the timing cover to swap the timing set over to the 454 (he ran on a very tight budget). I couldn't believe it, then he explained to me why he used them, and the talk drifted into using low stock volume/low pressure oil pumps to take more "drag" out of the assembly.

There were other conversations about how he had the crank journals ground and rods resized so they would live at high RPM's w/o issues.

Those early experiences were good for me and very quickly took me OFF the path everyone else was taking.....double roller timing sets, high volume/pressure pumps, aftermarket intakes, aftermarket carbs/distributors. Gary even ran points in his race car to get some natural timing retard at high RPM's to pick up a little more ET/MPH.

He was a BIG advocate of GM factory camshafts and pointed me to the Direct Connection catalog for the Purple Shaft cam that ended up in the 440 powering my 1970 Roadrunner. It was LIGHT YEARS better than the nasty idling Crane Fireball cam I had installed at one point. Good lessons learned back then but there I go drifting off topic again........

[adynes]

Originally Posted by Cliff R

Gary even ran points in his race car to get some natural timing retard at high RPM's to pick up a little more ET/MPH.

I would question this. From what I've seen, engines want more timing at higher rpms than the mid range, a trend caused by decreasing cylinder filling or volumetric efficiency past the torque peak.

[Cliff R]

I really never gave it much thought until we replaced the factory points distributor in my good friends 406 SBC powered race car with an MSD billet distributor. Both were "locked out" so no timing curved involved. With total timing at 36 degrees the car slowed down after installing the MSD billet unit. Not much, about .03-.04 seconds and one MPH or so. It baffled me at that time that a solid state distributor would make LESS power than a prehistoric set of points, but it fell off some and that was the only change made to it.

None of this matters much over here in the street section, and not really much in the "race" section either.....unless you are running in a class where every hundredth of a second counts for something.......FWIW.....

[Formulajones]

I know in my LS tuning days where you can go in and change individual cells with a lap top, it was common to pull a pinch of timing in the peak torque areas and then add some timing in the higher rpm ranges.

Usually those engines being very efficient never liked much more than 28 degrees of total timing at WOT but you would see maybe a couple HP gain on a chassis dyno by adding a couple degrees above 5000-5500 rpm. My guess is where the ignition cycle is happening so fast it helped to put a little more lead in it. :shrug:

I don't know if this would be true for all engines, I've only seen it done with OBD 2 computer controlled stuff when LS engines hit the scene in 1997.

I do have a timing retard feature with an MSD box I can flip on at will, and I thought about playing with some timing retard at the top of the track just to see how it affects that engine. May or may not do anything, but it's there and super easy to experiment.

[70GS455]

Originally Posted by Formulajones

I know in my LS tuning days where you can go in and change individual cells with a lap top, it was common to pull a pinch of timing in the peak torque areas and then add some timing in the higher rpm ranges.



Usually those engines being very efficient never liked much more than 28 degrees of total timing at WOT but you would see maybe a couple HP gain on a chassis dyno by adding a couple degrees above 5000-5500 rpm. My guess is where the ignition cycle is happening so fast it helped to put a little more lead in it. :shrug:



I don't know if this would be true for all engines, I've only seen it done with OBD 2 computer controlled stuff when LS engines hit the scene in 1997.



I do have a timing retard feature with an MSD box I can flip on at will, and I thought about playing with some timing retard at the top of the track just to see how it affects that engine. May or may not do anything, but it's there and super easy to experiment.

It was true of my engine, a BBB. Like most, I had my distributor set up with the standard config: 20 deg of mech "all in by 2800". After taking video of the timing marks at WOT on the dyno and noticed the timing jumping around a lot at high rpms, at the request of the dyno operator I put in heavier and heavier springs. The jumping went way down. And the numbers improved. We ended up with the mech advance stopping moving at 5500 rpm. We had the highest torque numbers and highest hp numbers by delaying the advance curve as much as possible.

Sent from my SM-T817V using Tapatalk

[Stan Weiss]

Almost 60 years ago. Bill "Grumpy" Jenkins used a dual point and switched points in high gear to retard the timing.

Stan

[Formulajones]

Originally Posted by 70GS455

It was true of my engine, a BBB. Like most, I had my distributor set up with the standard config: 20 deg of mech "all in by 2800". After taking video of the timing marks at WOT on the dyno and noticed the timing jumping around a lot at high rpms, at the request of the dyno operator I put in heavier and heavier springs. The jumping went way down. And the numbers improved. We ended up with the mech advance stopping moving at 5500 rpm. We had the highest torque numbers and highest hp numbers by delaying the advance curve as much as possible.

Sent from my SM-T817V using Tapatalk

That's pretty interesting.

[Formulajones]

Originally Posted by Stan Weiss

Almost 60 years ago. Bill "Grumpy" Jenkins used a dual point and switched points in high gear to retard the timing.

Stan

I've read that somewhere before. I guess he had the other set of points adjusted with a longer dwell time that would retard the timing event slightly. Pretty sneaky way of doing it with basic parts.

[70GS455]

Originally Posted by Formulajones

That's pretty interesting.

I learned a lot doing the testing. What I "thought" was going to work almost never did. Best tq was with lower timing and best hp was with higher, up to a point. Best overall numbers were with 38 deg, in at 5500. The usual street build specs, 10.7 CR, AL heads, 93 non ethanol pump gas, 236 HR cam on 113 LSA in at 108, NGK plugs with 7 heat range, 8.0 DCR

From looking at video, timing was around 33 deg at 3200 increasing to 38 at 5500

["QUICK-SILVER"]

Originally Posted by Formulajones

I've read that somewhere before. I guess he had the other set of points adjusted with a longer dwell time that would retard the timing event slightly. Pretty sneaky way of doing it with basic parts.

Points are staggered in a dual-point distributor. Leading set starts coil charge and trailing set ends coil charge. Makes for more dwell time than you can get with single points. Need more dwell time to turn high RPM's. Close point gap helped even more but required a HD condensor. That arrangement required a higher ohm ballast resistor for street use, that you bypassed for high RPM racing.

The timing change in high gear (high speed) had to do with air pressure created by a forward facing scoop.

FWIW Clay

[Formulajones]

I know how dual points work but that's not how the article reads. Grumpy explains that differently.

I would like to know how a forward facing scoop retards timing in high gear though. That's a new one on me.

[Tom Vaught]

If you read Hugh Macinnis Book on turbocharging or some of the other books on higher density mixtures in the cylinders, you will see that they say "not as much timing is required as the power from the denser charge increases". In Macinnis book he describes doing a timing retard function with dual points where when the engine sees boost, the pressure switch opens and the one set of points is removed (as is the extra dwell timing).

In Jenkins case, a properly designed Hood Scoop effectively increased the intake charge density into the engine. At the speeds that he was running, he found more power by also reducing the timing (removing a set of points) during the top end charge.
The FORWARD FACING SCOOP ALLOWS YOU TO RETARD TIMING AT HIGH SPEEDS AS THE SCOOP INCREASES CHARGE DENSITY.
You still need to incorporate the timing retard into the ignition system.

ALL of the MSD Boost Ignition Systems had the capability to remove timing when the charge density increased.

It is all right there in the books.

Tom V.

[Formulajones]

Yeah okay I understand that stuff. The way Clay briefly mentioned it made it sound as though the scoop was doing it.

Probably should be noted, most of his cars had rear facing scoops. What many referred to as the Grump Lump. Only a couple of his cars later had forward facing scoops. His 72 vega comes to mind. I think later before his 70 camaro became obsolete it got a forward scoop for a short time.

[Cliff R]

"In Jenkins case, a properly designed Hood Scoop effectively increased the intake charge density into the engine. At the speeds that he was running, he found more power by also reducing the timing (removing a set of points) during the top end charge."

Good info Tom. I would suppose one would see a slight increase in charge density with most varieties of "fresh" air system, Shaker, Cowl induction, or inlets open to the grill area, etc........

[Formulajones]

I've tested most of those variations of cold air inlets at the track having a variety of muscle cars here with different style hoods. By far the most effective and the one that sees the most loss when blocked is my Formula. A couple of the ZL2 setups I've played with actually work well, just not as much of a change. Did the "remove the high beam headlight" cold air deal on a car I ran in UMTR and that worked extremely well, as well as using a dual inlet with 4" tubes up to the grill area.