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Firing of engine for first time in car...have questions, need advice

rrTor-Red

rrTor-Red

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Fired my engine for the first time in my car. Engine builder built it, dyno'ed, etc. Had the engine in the car for a while but have questions, needing advice. Engine is a 400 stroked to 470. Hooked up a timing light prior to firing. Fired the engine and the timing light read 32* while on the dyno sheet said 18*. Also, RPM was high. I didn't run it for long, only a few minutes. Questions I have is the timing, RPM, and the idle might need adjustment. What other info needed for help? I got nervous because I didn't want to hurt or ruin anything so I didn't run it for long. I'm probably missing pertinent info so just ask

400 Block to 470
Quick Fuel 850 carb

Thanks FBBO!
 
18° at idle is ok. Put your light on it, twist the distributor (vacuum advance disconnected and plugged) to get the 18 and then throttle it up to around 3000rpm and note when timing begins to advance and what it tops out at..34-38 is ideal for most big-blocks, my 440 likes 20 at idle and about 38 total with the aftermarket cam..then do your carb adjustments from there..the idle speed will definitely change when adjusting the timing that's why start there first
 
When you say idle speed was high what was it? The timing could be 32* if the RPMs are over 2000.
 
rrTor-Red said:
Fired my engine for the first time in my car. Engine builder built it, dyno'ed, etc. Had the engine in the car for a while but have questions, needing advice. Engine is a 400 stroked to 470. Hooked up a timing light prior to firing. Fired the engine and the timing light read 32* while on the dyno sheet said 18*. Also, RPM was high. I didn't run it for long, only a few minutes. Questions I have is the timing, RPM, and the idle might need adjustment. What other info needed for help? I got nervous because I didn't want to hurt or ruin anything so I didn't run it for long. I'm probably missing pertinent info so just ask

400 Block to 470
Quick Fuel 850 carb

Thanks FBBO!
Click to expand...
First thing to look at is oil pressure and leaks ( coolant,oil, trans) turn idle down to around 900 or lower check timing at idle 18 to 20 is pretty standard for initial with 36 or so total. Look at throttle linkage make sure its fully returning to idle before making any adjustments. Also verify all vacum related lines are hooked up before making any adjustments. Im assuming it ran and idled fine on dyno. Just go over the basics first.
 
Big blue said:
First thing to look at is oil pressure and leaks ( coolant,oil, trans) turn idle down to around 900 or lower check timing at idle 18 to 20 is pretty standard for initial with 36 or so total. Look at throttle linkage make sure its fully returning to idle before making any adjustments. Also verify all vacum related lines are hooked up before making any adjustments. Im assuming it ran and idled fine on dyno. Just go over the basics first.
Click to expand...
Also if your running an msd ignition make sure distributor wires are not backwards or it will idle high and over advance timing?
 
Unbolt the throttle cable and start it before you do anything else. Sounds like the throttle is open a little. You cable may not be adjusted right or too short depending. Unhooking it wil get it back to the way it was on the dyno.
 
moper said:
Unbolt the throttle cable and start it before you do anything else. Sounds like the throttle is open a little. You cable may not be adjusted right or too short depending. Unhooking it wil get it back to the way it was on the dyno.
Click to expand...

I started it twice. One with the throttle hooked up and the other with. Both times, I ran it for a few minutes. Both times it was the same
 
Big blue said:
First thing to look at is oil pressure and leaks ( coolant,oil, trans) turn idle down to around 900 or lower check timing at idle 18 to 20 is pretty standard for initial with 36 or so total. Look at throttle linkage make sure its fully returning to idle before making any adjustments. Also verify all vacum related lines are hooked up before making any adjustments. Im assuming it ran and idled fine on dyno. Just go over the basics first.
Click to expand...

I/we checked for leaks, on the start up, none on everything. No leaks surprised us to begin with. As I replied before, started the engine with and without the throttle linkage hooked up, same. Oil pressure was good. Did pull vacuum lines off and seem to be working. It idled high. This has me stumped. Having a friend of mine who has build his own NHRA dragster, worked for the same Chrysler dealership for 35+ years, and rebuild my rear end and tranny on the car, to come over and take a look but he won't be able for a couple of weeks. Just looking for some answers
 
Idle is
beanhead said:
If your timing at idle is 20° or below your throttle plates may be open too far...try this. They use a demon but it's the same basic design as yours
http://gasalley.thetumbleweeds.net/tech_archive/general/DemonIdle.htm
Click to expand...


Initial idle at start up is 32, not 20. Dyno sheet showed the idle at 18 at start up. I might have found part or solution to this, IDK. My builder used FBO ignition kit from 4 seconds flat. On the web page, it said to by-pass the ballast. Below is the link

http://www.4secondsflat.com/Ignition.html
 
Regardless of which ignition controller is used, somehow it seems the distributor was moved, if they set it at 18 and its now at 32. Adjust the distributor back to 18 and see what happens. The ballast bypass is for their specific coil and controller but that does not affect idle timing or rpm
 
And make sure your vacuum advance is disconnected and plugged at the carb!
 
Last edited:
Something else...COULD the shop have set timing with no vacuum advance hooked up (correct) but then connected the distributor vacuum line to 'manifold' vacuum, as I thought that's how fbo likes to do it? Manifold vacuum will add timing at idle......factory used the 'ported' or 'timed' vacuum connection, which only adds timing at cruise speeds. (Big can o' worms with this statement) but personally I would use the ported vacuum or none at all...You don't need the distributor advancing at idle but in the mid-rpm range for some extra mileage and lower temps AGAIN that's only my opinion, fbo likes their stuff running with the extra vacuum at idle. My car runs best with the advance unhooked and capped off, and I've tried it all 3 ways
 
As black64 said above, if the motor isn't at an idle, the timing WILL BE advanced! Look at the throttle arm on the side of the carburetor and see if the idle speed screw is sitting against the stop. Is it? If so, back out the screw a few turns and see if the arm still seats against the stop. If so, the idle should come down some. If not, something is hanging it open. Either fast idle speed screw, vacuum leak, or the base gasket/spacer . If the shop ran it in on their dyno, you don't have to worry about the break-in procedure...
 
rrTor-Red said:
It is
Click to expand...
Ok good...loosen the distributor clamp and twist that sucker counter-clockwise, that should lower the timing and rpm a bit..if your dyno dude set it at 18° that's where I would lock it down for now..this is assuming, like the others said, that your throttle isn't hanging open...make sure it's on the stops. When your timing is where you want you can adjust further with the throttle screws if needed. If the cam is fairly radical it probably will want to idle at minimum 900-1000, depends on your combo. Does the dyno sheet show an idle rpm?
 
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