Latest ZZ454 article is a load of crap

Anybody read through the article and closely examine the photos of the ZZ454 GM crate motor dyno test they did recently(March 09 issue)?  Notice anything, like, completely wrong?  Both in the magazine and on this website, you'll find the same glaring problem.  They start off the article saying they put a brand new(very shiny) Holley 770 Street Avenger carb on the engine.  Their photo matches this claim.  Then after a few below average dyno tests with that carb, they claim to switch to a Holley 950 carb, and they have photos to back it up.  They claim to get some great numbers on the dyno with this 950 carb.  Okay, so far, so good, no problems.  HOWEVER, they then claim to switch back to the shiny Holley 770 and realize they had a linkage problem before.  They claim to solve that vague and mysterious linkage problem, and with that 770 carb "right out of the box", they get their final dyno numbers of around 500HP.  Okay, then what the hell is this 3rd carburetor they have pictured in the final photos, both on your website and in the magazine?  This mystery carburetor that they never make any mention of definitely isn't the 770 or the 950.  What the heck happened here?  Seems like somebody isn't telling the truth here.  The reason I have such a problem with this article is because I just purchased a ZZ454 and I also experienced the same problems they did right out of the box and I'm just freakin dying to know what they truly did to get the 770 to work(if in fact they did actually pull those final numbers).  

Ya I see what your talking about one looks like a street avenger, then a holley pro series HP, and the third looks like a basic holley vacuum secondary.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

chr2002ca ,

I have the same motor zz454 and carb 770 street avenger and was wondering what was the problem with that configuration.

A mechanic is putting my engine together and should crank it for the first time hopefully next week.

What exact problems are you experiencing ?    just so i can have and idea.

Thanks.  

Hi.  Cool.  It's nice to meet someone here that also has a new ZZ454.  From day one I've experienced basically the same problem they described and still haven't figured it out.  The engine isn't running as smoothly as it should and it's certainly not putting out the power it should.  Also has a bog when you hit the throttle hard.  I've run so many tests to attempt to identify and fix the problem that I could puke. Still haven't figured it out, but I'm getting close.  This week I'm going to install a FAST dual-sensor air/fuel meter kit to hopefully get a real clear view as to what's going on.  I'm thinking it's some kind of fuel delivery problem at this point.  Either that or somebody played a joke on me at Hedman or Flowmaster and clogged one of my primary header tubes or exhaust pipes!

Vacuum is good(idle: 18Hg, 2000 RPM: 21Hg).  Timing is 16 BTDC with total at 36 BTDC at 3000 RPM with vacuum plugged.  Vacuum advance is hooked up to the vacuum port on the carb.  I tried plugging the vacuum advance and also tried manifold vacuum and it made no improvement in the overall problem or performance.  Different timing settings only made things worse.  These timing settings should be good for this engine.  The documents that come with your engine will give you a much different timing setting but those settings were way off for me and for others I have chatted with that are running this engine.  Even the article recommends something very close to these settings.  Spark plugs look a little black, but I've seen worse.  Fuel pressure is steady between 7 and 7.5.  

Here's what else I've tried:

1.  2 different ignitions(HEI and MSD 6AL), multiple ignition tests and individual spark plug tests.  No change or problems found.  
2.  3 sets of new spark plugs.  No change.  When previous 2 sets of spark plugs were removed, they all matched in appearance.
3.  3 sets of spark plug wires.  No change.
4.  2 Brand New Holley 750 Vac Sec, electric choke carbs(pretty much the same as the 770 Avenger).  No difference in behavior between carbs.
5.  Different accelerator pump cams and nozzles(helped the bog a bit, but I don't think that's the problem as it didn't solve the overall problem.
6.  Compression tests on each cylinder.  Checked out okay.
7.  Measured rocker arm travel on each rocker arm.  Checked out okay.
8.  Tested fuel line from pump to tank(brand new fuel line, pickup, and tank).

You can see my setup and the details of my build here:  www.69CamaroProject.com

Please keep me updated on your progress!!  I really hope yours works great right out of the box!  If so, I hope we can chat about your setp.  

-Chris
chrisr@69CamaroProject.com  

While I am not an expert, I recently had similar problem and it was my fuel pump! It would bog and no floor it POWER, I changed pump and it's like a different truck. I would at least get a fuel pressure gauge and cross off this option, don't know but also could be sock in tank. Ben  

Thanks Chris i definitely will get back to you as soon as i hear it start .

my setup is ZZ454,MSD-6AL-6200, MSD-8361 Distributor, MSD-8202 blaster 2 coil, 770 street avenger, k&n air filter, Holley HP Series Fuel Pumps PN# HLY-12-125, new fuel lines but same tank .  

i will get back soon hopefully!  

That's actually a similar setup to what I started out with.  I used the MSD 6AL and Blaster 2 coil, but then I just switched back to the HEI unit that's built into the GM HEI distributor that I purchased.  After I purchase the MSD 6AL Super HEI kit, I was doing some reading and learned that the multiple spark discharge that the 6AL brags about isn't possible if you use your stock distributor and you'll only get a single spark.  So I wasn't getting my money's worth, so I switched back to just the HEI unit itself.  I'm using a Holley mechanical pump and I think the problem might be somewhere in my fuel system.  I was actually thinking of trying a different fuel pump, so I definitely look forward to your results considering you're using the electric Holley.  I'll let you know if the FAST air/fuel meter tells me anything.  Hopefully I'll get that installed this weekend.  

Hi Ben,

Thanks for the advice.  Yes, I'm leaning toward the fuel pump also, even though it's brand new.  I do have a fuel pressure gauge running off my fuel line as it enters the carb and it reads a steady 7.0 to 7.5, however this does not tell me if I'm getting the actual fuel flow(GPH) that I need.  I've checked the float levels inside the carb and my carb doesn't seem to be starving for fuel, but I can't be for certain.  Hopefully the FAST air/fuel meter will give me some clues about that.  Maybe the digital display will read:  Sock in your tank!

-Chris  

You can have fuel pressure without fuel flow.=  so maybe when just idleing or free reving it it is still reading fuel pressure ok!
 But when the engine is under load and is craving the fuel. bang the fuel bowls are virtually emptying only surviving on a trickle=  NO FLOW !
   I had this horible problem when i first got my 400 small block going!


also dont know what model cars these engines are in? but by chance did the car originally have a points distributor ? and still have an inline resistor in your power suply to your ignition?    just a thought.  
there is no substitute for cubic inches

i have a 1964 impala super sport.  

this is a article i was reading the bottom line is to make sure there's no TV cable slack
with the carb @ wide open throttle.

http://www.cpttransmission.com/tech_tvcable.htm



the TH200-4R's wide pan is (somewhat) reminiscent of a Turbo 400, so we feel it doesn't really detract from the car's stock appearance.
If we had to characterize one annoyance of the late-model GM overdrives, it's their sensitivity to TV-cable adjustment. Incorrect throttle-arm geometry can wreak serious havoc on the internals of a TH200-4R, dramatically shortening its life span and giving poor driveability. Fortunately, a few parts make it easy to get the geometry dead-on. As shown in an accompanying photo, we bolted up a modified bracket from a 307ci/TH700-R4 '85 Olds Delta 88 to securely retain the snap-in TV-cable sheath. The end of the cable attaches to a stud mounted on the throttle arm of your carb or throttle body. This is where the geometry gets critical--this stud must follow a specific arc as the throttle is applied. The stud must lie at a radius between 1.094 inch and 1.125 inch from the pivot (the centerline of the throttle shaft). Furthermore, when the throttle is cracked about one-quarter open, the stud should lie at the bottom of its circular arc. If these two criteria are met, it's just a matter of lengthening or shortening the cable length to ensure the cable doesn't bottom out before WOT is reached. CPT offers specifically engineered stud fixtures for Edelbrock, Quadrajet, and Holley carbs that ensure dead-on stud geometry. Simply bolt the proper fixture to the throttle arm and the stud is right where it should be--easy. If you want to rig something up yourself, CPT can provide a drawing of the correct geometry.  

In anycase a solid "hotrod" motor that can make some scary dry posi wheel burning power.  

Ladies and Gentlemen,
           As the author of the GM Performance Parts 454 Dyno test, I feel it is my obligation to you, the readers, to respond to this thread as there have been many questions pertaining to the amount of horsepower we made and the way in which we made it. The truth of the matter is, there was no smoke, nor mirrors used to create the 500 horsepower/550 foot-pounds or torque that we ended up with. We tried three separate carburetors on the ZZ454 and all were able to get us to the number we were looking for once they were sorted out.
          Let me start off by saying that the entire time we had the motor on the dyno (2 days total), we were using Joe Gibbs Driven Break-In Oil, which is a non-synthetic blend specifically used to seal a motor properly and seat lifters. This oil is a 15-40 weight and it was never changed out for a lighter weight oil. The use of a low amount of oil, or a thin weight oil (much like the ones used in purpose built race cars) will have made more power in the long run. Also, we did the entire test on 93-octane fuel from the Exxon station down the street. Race gas was absolutely not used. The biggest horsepower gains we saw was a direct result of added timing. GM Performance Parts recommends 24-degrees in this particular motor. We started there and slowly bumped it up 'till the motor simply started making power. All pulls were completed with a water temperature of 150-degrees. We were not monitoring oil temperature.
         As for the carbs, we started with a 770-cfm Holley directly out of the box and could not make more than 440 horsepower no matter what we changed. We finally decided to throw on a 950-cfm Holley that Dave Jack from Dave Jack Cylinder Heads has used for years when such problems arise. The motor came to life and made 478 peak horsepower with low timing. That night, we took the 770-Holley home, ripped it apart, and found that the only problem was in the primary and secondary linkages. In case, we were unable to resolve the carb problem, I brought a 780-cfm that we have often used in NHRA Stock Eliminator and would give us a more accurate depiction of what a customer would use rather than the 950. With my personal 780 on the motor, we tuned the motor to 508 peak horsepower. We were ecstatic and decided to make sure we could duplicate those results with the new 770 we were given from Holley. Right off the bat, the original Holley we started with made 492 horsepower. We had done everything we could without touching the heavy weight oil, adding race gas, or messing with jet sizes. It was that that point that we realized out last dyno pull was made at close to 200-degrees. We let the motor cool to 135-degrees and gave it one more shot. Bingo. 502 horsepower.
         Once the story hit the shelves, I realized that we (meaning I), had made a mistake with the pictures showing the linkages. At the time this story was hitting the stands, Source Interlink Media was in the midst of a reorganization at the heart of which resulted in us without a copy editor. On another note, many people are doubting that we had a 454 cubic inch motor at all. Some blamed us on using a large motor, larger camshaft, or race gas. I assure you that this was not the case and will be disassembling the big block in the near future so I can show all of your dedicated readers that we were not trying to pull the wool over your eyes.
         I apologize for any misunderstanding that arose from the story and apologize for a mistake on my part. Keep checking our video section as I will be taking a cylinder off and verifying cam lift, bore, and stroke.

Thank you for reading,

Michael Ficacci  

What you are saying is that you pulled 502 horsepower with the ZZ454 / 770 street avenger ?  

Yes, we made 502 horsepower with the ZZ454 with a 770-Holley Street Avenger, timing in the high thirtys, and on 93-octane fuel.