Some race shop pics

[AlNyhus]

Then there was the Frantz remote filters with toilet paper as the filter media. My Dad had a '56 Ford pickup that someone had put one of those on it. When I was young and scrounging the local salvage yards for stuff, I saw quite a few of them.

 

[urbanrifleman]

The Sniper setups are generally pretty decent. They have some quirks in the fuel pump wiring circuit that should be addressed during installation to save you from being dead in the water with no power at the pump. If you haven't purchased a setup yet, the Sniper II (constant self tuning) systems have most of these updates. I'd strongly suggest the optional Power Distribution Module (PDM) along with their fuel pump system. It will greatly simplify things.

A pals Pro Street Corvette has the original Sniper system on a big inch BBC. It works well after the fuel pump quirks mentioned above were worked out. He got lucky...it died as he was pulling into his driveway.

My 2 cents but as always, do your homework. -Al

I made the decision to just go with a carb. I think I'm going to get an Eldebrock.

 

[jackieschmidt]

I made the decision to just go with a carb. I think I'm going to get an Eldebrock.

The Edelrock carbs are basically a AFB. They are easy to tune if you get the jetting and rod kit.
They also make a modern version of the venerable Quadrajet.
Both are great street carburetors on medium size engines.

 

[Tricky5225]

The two to be tested. Left is a 283-220 Super Stock engine, right is a 265" Super Stock engine.

The 283 was first up. A final check of the valve lash before warm up.

Like with anything, there's always the behind the scenes maintaining that takes place. Bob and I attend to some plumbing stuff that supplies water to the servo valve that feeds the dynos water brake from a holding tank. Think of it as a very complex version of the tank on a toilet that has to constantly feed a precise amount of water into the tank while managing the overflow at the same time. This keeps the water temp in the water brake consistent so the dyno numbers stay consistent.

Warmed up, no leaks,water brake servo valve is set, timing is checked a final time and it's ready for the first baseline pull.

Coming up on the throttle. The pull begins at 6,000 which is where the servo holds the rpm until the
run program' button is activated on the console. It has too much oil pressure but that was intentional for this test.

Off the throttle and coming back down.

Next, we go right back within 5 minutes and repeat the same cycle. On the first pull, even with the oil temp at 140 (which is the baseline oil temp for each pull) the fresh oil hasn't been 'knocked down' yet. New oil molecules are like jagged round spheres. The 'spikes' of the molecules hold back a bit of power until they have been crashed and tumbled together to remove the 'spikes'. The next pull on 'knocked down' oil will always make some more power. On this one, it made another 6 horse power. It's at this point that meaningful testing can begin.
Without divulging what was done, 12 pulls later the engine has made significant improvements. It got loaded up and a satisfied owner headed back to Kansas.

Next up was the 265" engine. Good progress was made and based on the direction things were taking, the decision was made to hold the project over and pick up with it next week with some cam changes.

Hope some of you enjoy this stuff. Good shootin' -Al

Al
Looks like some of Bich's handywork

 

[Tricky5225]

Al
Looks like some of Bich's handywork

By the way it's his B day today

 

[AlNyhus]

With those two SBC's done, the next one up was this '69 396-375 NHRA Stock Eliminator engine. This was my new Ridgeline's first 'load'.

It made very good power. The data suggested a couple areas where some crumbs might be revealed. Yesterday, we did some camshaft work and will test again tomorrow.

 

[jackieschmidt]

Al, what are the rules now when it comes to cylinder heads in Stock Eliminator.

Way back in the Cretaceous Period, we had the big port open chamber cast iron heads or the round exhaust port Winters Casting Aluminum Snowflakes.

We found that on classes where you could do nothing to the heads, (APBA Super Stock), the iron heads made more power and of course, sealed a heck of a lot better, as the rules prohibited adding that bolt in that space between inside cylinders.

What casting is on that 396?

 

[cp generation]

Al, what are the rules now when it comes to cylinder heads in Stock Eliminator.

Way back in the Cretaceous Period, we had the big port open chamber cast iron heads or the round exhaust port Winters Casting Aluminum Snowflakes.

We found that on classes where you could do nothing to the heads, (APBA Super Stock), the iron heads made more power and of course, sealed a heck of a lot better, as the rules prohibited adding that bolt in that space between inside cylinders.

What casting is on that 396?

That missing bolt has been a PIA since i was a kid in the 60's just cant understand why it is such a big deal to put it in, the ZL1 had it. was a real problem on a blower motor pushing the gasket out. I understand stock.

 

[jackieschmidt]

That missing bolt has been a PIA since i was a kid in the 60's just cant understand why it is such a big deal to put it in, the ZL1 had it. was a real problem on a blower motor pushing the gasket out. I understand stock.

In APBA Super Stock, we couldn’t even run needle bearing rocker arms, the rules mandated the stock stamped steel units, or TRW replacements.

That meant you had to flood the top with oil, but even then they would overheat and gall. 7200 rpm for five laps was pushing them to the limit. The good thing was I had a sponsor ship with TRW and Seal Power and got them for free, along with rings, bearings and a few other items.

The worse thing about the balls over heating and galling was snapping a rocker arm stud. Or worse yet, with the Chevy aluminum head, pulling the aluminum mounting boss right out of the casting.

 

[AlNyhus]

The head rules for NHRA Stock Eliminator are pretty strict. The heads have to be what came on the production engine or an NHRA approved replacement. These are the G.M. Performance #401 casting heads, which NHRA accepts as a replacement for the rectangular port iron heads. They are better in some respects and worse in others. They do get 80 lbs off the nose of the car, which is significant as a 9" tire is all that's allowed. Valve size has to remain stock, no porting, combustion chambers and ports have to hold the stock volume in cc's. Intake and carb have to be stock production stuff or an NHRA approved replacement for the engine you're working with. The cam also have to have the factory lift for the engine. In the case of this 396-375, it's .520 intake and exhaust. The lifters have be the style that came with the engine...flat tappets on this one. Needless to say, the phasing of the lobes is where lots of gains come from. And lots of pain, too. The lobes on these are incredibly aggressive and managing the lifters and stabilizing the valve train is very, very important not only to keep from hurting stuff but to make power in the upper rpm area.

Our camshaft work didn't advance the power...in fact, it hurt it by more than it should have. This led us to look at some other areas that may have been limiting the power more than we realized, even before the cam change. Some new pieces will be here today and we'll go back to the beginning, get a new baseline and go from there.

That's the nature of dyno work with these severely rules restricted engines. Often, a loss can lead you to explore areas that end up giving you a gain. It's a cycle you repeat over and over to get these engines to make the impressive power they do.

Good shootin' -Al

 

[jackieschmidt]

The head rules for NHRA Stock Eliminator are pretty strict. The heads have to be what came on the production engine or an NHRA approved replacement. These are the G.M. Performance #401 casting heads, which NHRA accepts as a replacement for the rectangular port iron heads. They are better in some respects and worse in others. They do get 80 lbs off the nose of the car, which is significant as a 9" tire is all that's allowed. Valve size has to remain stock, no porting, combustion chambers and ports have to hold the stock volume in cc's. Intake and carb have to be stock production stuff or an NHRA approved replacement for the engine you're working with. The cam also have to have the factory lift for the engine. In the case of this 396-375, it's .520 intake and exhaust. The lifters have be the style that came with the engine...flat tappets on this one. Needless to say, the phasing of the lobes is where lots of gains come from. And lots of pain, too. The lobes on these are incredibly aggressive and managing the lifters and stabilizing the valve train is very, very important not only to keep from hurting stuff but to make power in the upper rpm area.

Our camshaft work didn't advance the power...in fact, it hurt it by more than it should have. This led us to look at some other areas that may have been limiting the power more than we realized, even before the cam change. Some new pieces will be here today and we'll go back to the beginning, get a new baseline and go from there.

That's the nature of dyno work with these severely rules restricted engines. Often, a loss can lead you to explore areas that end up giving you a gain. It's a cycle you repeat over and over to get these engines to make the impressive power they do.

Good shootin' -Al

Amazing stuff, Al.
I said in jest that we were racing back in the Cretaceous Period. Seeing some of the things “Hot Rodders” do now makes me think we were more Pre Cambrian.

 

[AlNyhus]

Amazing stuff, Al.
I said in jest that we were racing back in the Cretaceous Period. Seeing some of the things “Hot Rodders” do now makes me think we were more Pre Cambrian.

We resprung the valves today and used a tool steel retainer. That cured the problem of the fuel curve getting wonky starting at 7,000. Even though the original springs on the build were more than adequate, the lifter speed around the base circle of the lobe was causing some valve spring harmonics at higher rpms....enough that the springs were surging and the valves not sealing properly. Here's a few pics while we were doing it. We put some air into the cylinders to hold the springs on their seats while the springs and removed and new ones installed. The LSM stud mounted spring tool makes a tedious job pretty quick. We got the old gear off, checked all the spring heights checked, seat shims figured out, the new springs/retainers installed and the valve lash reset in a bit under an hour.

Here's a spark photography video of valve spring surge so you get an idea what we were up against:

 

[Olde Man]

Thanks for that video. Clear as mud.

 

[AlNyhus]

Thanks for that video. Clear as mud.

If you look at the top of the valve stem, you can see that valve itself is 'bouncing' from the spring harmonics. This slightly moves the valves from their seats...which causes the air signal to to the carb to change...which makes the carb go rich to try and compensate for it...which showed the fuel curve data start getting wonky on the data display. So what looked like a fuel curve problem was actually valve train instability.

It's just like a precision rifle...everything has to work together.

 

[jackieschmidt]

If you look at the top of the valve stem, you can see that valve itself is 'bouncing' from the spring harmonics. This slightly moves the valves from their seats...which causes the air signal to to the carb to change...which makes the carb go rich to try and compensate for it...which showed the fuel curve data start getting wonky on the data display. So what looked like a fuel curve problem was actually valve train instability.

It's just like a precision rifle...everything has to work together.

We used to call that “reversion” with the old Tunnel Rams, like the Edlbrock TR-2X. If your springs were too light, you would get exactly the same thing, putting back pressure into that huge plenum, confusing the 850’s.
Somebody would finally say…..”I wonder if we are maybe floating the valves”…….Bingo.

As you probably remember Al, back in the ‘70’s, cam profiles got way ahead of spring technology. I can still remember when we bought our first set of triple wound 1 5/8 diameter “King Kong” springs from Cam Dynamics to go on our 399 inch SK motor, which were geared to hit 7500+ rpm on the straight always. My standard hand operated spring compressor wouldn’t even compress them enough to install them.
Of course now, those would darn near be considered “break in” springs in some applications.

 

[Judd]

That’s wild, thanks for sharing Al.

 

[AlNyhus]

With the engine making good power, we drained the break in oil (high zinc content) and put in the race oil. Again, we have to do one hard pull on new oil to knock it down. The second pull will always be from 4-6 hp better.

Well, the first pull numbers were down 14 hp...not a good sign. The second pull pull only came up 3 for a net loss of 11 hp from the break in oil to the race oil. After some discussion, we decided to change to a non synthetic race oil from the same mfg and the same weight. I had some suspicions that the oil ring tension might be borderline. The first pull with the dinosaur oil equaled our best pull from before. The second pull picked up 6 hp from that. After all was said and done.. we ended with a pretty significant gain.

You never know where you're going to find or lose power on these engines. You have to look under every rock and then under the rocks underneath the rocks. Dyno time like this is not for the faint of heart, budget wise. And the dyno itself has to be repetitious of itself to let you seperate the pepper from the fly poop.

I consider myself very fortunate to be involved with a shop like this. The constant learning makes it worth the effort.

"Problems worthy of solving prove their worth by fighting back" -Albert Einstein

 

[Alex Wheeler]

Thats interesting. Same viscosity oils just a syn vs non syn? Out of curiosity, what weight oil are you running? If you know what pressure and main/rod bearing clearances? When I was messing around with this stuff ( amateur stuff compared to what your doing) the thought was more clearance and thicker oil. I would assume that mentality has changed. I remember being taught that the oil could wrap around the crank like a rope, which was why all the oil scrapers in the oil pan. I learned from a guy who built offshore race engines. They were running wide open for a long time.

 

[AlNyhus]

As you probably remember Al, back in the ‘70’s, cam profiles got way ahead of spring technology. I can still remember when we bought our first set of triple wound 1 5/8 diameter “King Kong” springs from Cam Dynamics to go on our 399 inch SK motor, which were geared to hit 7500+ rpm on the straight always. My standard hand operated spring compressor wouldn’t even compress them enough to install them.
Of course now, those would darn near be considered “break in” springs in some applications.

Jackie, on these Stock Eliminator big block Chevies, the seat pressure will be around 250. The springs are such that at .520 lift (less the valve lash), they are right at 600 lbs. A good rule of thumb is about 115 lbs per .100 valve lift.

On the splayed valve Competition Eliminator stuff, the open pressure is a bit over 1,000 lbs. You actually have to be damn careful turning these over to set the valve lash. If they gallop off the closing ramp of the lobe nose, you can get hurt....have seen more than a couple broken wrists and distal radius or ulna fractures...not funny stuff at all. And the ignition systems generate enough amps to kill you deader than a smelt in the wong situations. I'm damn careful working around them. Serious shit.

 

[AlNyhus]

Alex...yep. Same oil but just synthetic versus dinosaur oil. These big block Chevies like right at .003 for rod and main clearance and .0032 won't kill you. Most guys are using the 5-20 oils but this builder prefers the 10-30 for the DLC coating on the tool steel lifters. The ring packages in these are very sophisticated with a Napier style second ring to take a bit of load off the oil ring. That lets the oil ring tension get pulled back. On this engine, it only takes 6 lbs/ft of torque to turn the rotating assy. (short block).

On pressure, there's more to be gained in this engine. For example, on my 327 Stocker engine, we modified the oil pump to internally bypass the excess oil volume. We brought the pressure down from 50 at 7,000 to 30 at 7,000 and 'found' 7 hp.