455 Dyno'd today & I am horrified!!

A 1973 Quadrajet completely gone through by Ken.

As you guys give me more ideas, more stuff comes to mind. I also just remembered that I saw the carb gasket on my parts cart. Could that keep the butterflies from fully opening?

He is supposed to be there tomorrow & I'm going to try & get my eyes on the parts I can see. Maybe just get him to take it right to 32*.

On a good note mid 70's for oil P.S.I. all through the RPM range.

Kyle

 

Don't take this the wrong way but that's a little steep for an engine brake in on the Dyno. Did they also build the motor ? Oil pressure sounds good hopefully it's just a secondary not opening up, if they are they may not have degreed the cam correctly, could be retarded.

 

They did build the motor. I got the 9 key way timing set from TA. When I was there for the test fit he put it on at 0*.

They build race motors so my hope is that they know enough to degree a cam correctly.

How can I tell if the cam isn't degree'd correctly?

Kyle

 

At this point you cant know for sure unless you pull it apart and put a dial indicator on the lifter or push rod and a degree wheel on the crank. Its a question Id be asking. Most shops keep notes on the build for future reference.

 

I'm just more worried something isn't set up right. I wonder if my secondaries are opening etc. These numbers are low!

Seems to me they seem wary when I say that Buicks like between 32* & 36* of timing.

Hard part is I wasn't there for the build. So I have to take their word & trust they did things correctly.

Kyle

 

Yep. Was there for the whole session. When I commented on the numbers they said they were just breaking the motor in. Then I asked about timing & they told me 26*. They will keep advancing until the motor quits making power.

Would 8*-10* make that much of a power/torque difference?

That's what has me wondering about carb or cam degreeing issues.

Kyle

 

The TA timing set goes in on the 4A notch,...it has instructions in the box describing the procedure which differs from most timing sets

 

Dammit Hugger! Now I'm wondering if they degree'd correctly!

Kyle

 

I mean the notches are there to be adjusted but 90% of the time you'll end up on the 4A,...its been several months since I fooled with one but I do know there is a little instruction sheet in there, I mean if they degreed the cam and it cam in spec then its rite, you have to physically move the gear to advance or retard the cam

Let them do whatever they are doing if you come in around 350 to 400hp then I'd say its probably just what it is,..if they barely break 325 or so then there something amiss

I dont see the need for multiple pulls with that combo tho, maybe they uses chrome rings or something,..because with the cast or modern plasma moly rings it's ready to go to work after a couple heat cycles

 

I wouldnt get too high strung just yet. If this is a reputable shop, they know about what it should make and if something is hurt/outta whack I would sure hope they wouldn't spin it up on a Dyno any further knowing it's way down on power for some odd reason. If they're saying it's business as usual and they're gonna make the power runs next, let em do what you paid them to do. It's ok to ask questions and get info, you're the customer. But dont panic just yet IMO.

 

I know, I know. I can do a lot of work on cars but didn't feel comfortable building my own motor. They seem very reputable. It's just the fact that I have to let go of control....

Then the numbers I saw today were horrendous.

Kyle

 

Larry,

It looked very similar. I would like to think so.

Had the handle as a throttle control.

Only mine had crank & water pump pulleys on.

Kyle

 

Something is bad wrong, very bad. Either their dyno is broke or whoever built the motor got the cam timing way off. That engine would make better numbers than that with 4 spark plugs missing - fact. Hope you get it sorted out.

 

1. I suppose I understand setting the timing "conservatively" before the first dyno pull if someone else built the engine. I'd maybe set it at 30 degrees. 26 is just...crazy. AND THEY BUILT THE ENGINE! THEY SHOULD KNOW WHAT OCTANE IT NEEDS. For THEM to put the timing at 26 is not merely crazy, it's fookin' insane. A TOTAL waste of a dyno pull, AND with the risk of overheating the exhaust valves and exhaust system. There is nothing gained in "break in" with overly-retarded timing. It's just a matter of avoiding detonation.

2. What is the cranking compression? If the cranking compression isn't far off of expectations, the cam timing may be OK. If this shop screwed-up the camshaft position, you need to find another shop. My question--and I can't tell from the description given--is: Did they put the TIMING SET at "0", or did they put the CAMSHAFT "zeroed-in" at the cam-card spec? The way I understand it, this timing set needs to be 4 degrees advanced to get the camshaft "zeroed-in".