How to make a 350 start super quick?

[mcintyrederek]

My grandpa had a '76 LeSabre with a 350.  I can remember him cranking that thing up (warm) with nearly just a twist of the key.  I am trying to figure out my timing, and how to get it all set up to do the same.

The setup - A Goodwrench 350 crate motor with about 20K on it.  Driven easy, never abused.  Carb - Quadrajet.  Been rebuilt from bottom up and runs great.  Hooked a vacuum gauge to manifold vacuum, adjusted both idle mixtures for maximum vacuum then turned each screw out about 1/4 more turn.  Distributor is brand new, HEI type, magnetic pickup.  New plugs, wires, etc.  Starter just rebuilt, and I mean it really turns it great. 

I have a manual choke, and I can start it up without fast idle very easy and ease off the choke no problem.  I drive it 10 to 20 miles, and turn it off.  About 30 minutes later, it seems like it really wants to drag when starting (from warm).  I mean, about 2 to 3 seconds, then it sputters, and then cranks and runs fine.

My question to you is, what factors affect this starter drag?  I have set my timing to about 4 deg advance.  If I advance it any further, it knocks.  I have tried retarding about 2 degrees, but still the same thing.  My vacuum advance hose is hooked to PORTED vacuum.  What is causing my hesitant starts?  I am leaning to something may be wrong with the carb?  I didn't rebuild it, so I really don't know what I've got.  Your thoughts, please?

[thefarmboy21]

You sure it's not a starter issue? All out sbc derby motors crank fast, unless they're WAY outta time. Now they may not start fast but starter should take right off. Use big cables, big battery and make sure the exhaust isn't gettinh the starter too hot. Wrap some aluminum foil around it and see if it helps, then if so you can find a permanent solution.

[rich weyand]

Take the advance off ported vacuum and connect it to manifold vacuum.  That's emissions crapola.

Then set the timing to 16* BTDC.

http://www.corvetteactioncenter.com/forums/c3-technical-performance/60830-ported-vs-manifold-source-vacuum-advance.html

[Irish_Alley]

on a side note about your timing. for one like rich stated 16° is ideal. if your pinging at only 4° you have other problems, like wrong gas or your timing marks or balancer has moved. and on top of that your starter will slow down once the engine is warmed up and your timing is too far advanced. or your starter is heat soaked and is about to crap out on you. but 6° shouldnt be enough to slow the starter down

[mcintyrederek]

I never thought you were supposed to take the vacuum advance and hook it to manifold vacuum.  This is interesting.  I'll check that link you sent me.

Thanks for all replies, let me at least try that first.
Derek.

[mcintyrederek]

OK.. I hooked up the vacuum advance line to MANIFOLD vacuum and capped off the PORTED vacuum stub.  Now it idles like pure crap.  Am I supposed to adjust the idle mixture on the Qjet now?

Before I go out and mess with it again, here's what I plan on doing.  Tell me if I'm right or wrong.

This 350 has a compression ratio of 8.5:1 and a stock cam (Goodwrench crate motor).  It should run on 87 gas.

Step 1.  I will unplug the vacuum advance line and cap off the manifold vac. port at the carb, and adjust my timing to what you guys stated to be ideal.  I'll start at 10 degrees advance.

Step 2.  I will hook the vac. advance line up to the distributor.

Step 3.  At idle speed (700 or so) I will now adjust the idle mixture at the carb.

Is this the proper sequence of events?  How many turns CCW from base outward would be "about right" on a Quadrajet for idle mixture, just as a ball park?  I can adjust for maximum vacuum.

Thanks.

[rich weyand]

OK.. I hooked up the vacuum advance line to MANIFOLD vacuum and capped off the PORTED vacuum stub.  Now it idles like pure crap.  Am I supposed to adjust the idle mixture on the Qjet now?

Before I go out and mess with it again, here's what I plan on doing.  Tell me if I'm right or wrong.

This 350 has a compression ratio of 8.5:1 and a stock cam (Goodwrench crate motor).  It should run on 87 gas.

Step 1.  I will unplug the vacuum advance line and cap off the manifold vac. port at the carb, and adjust my timing to what you guys stated to be ideal.  I'll start at 10 degrees advance.

Step 2.  I will hook the vac. advance line up to the distributor.

Step 3.  At idle speed (700 or so) I will now adjust the idle mixture at the carb.

Is this the proper sequence of events?  How many turns CCW from base outward would be "about right" on a Quadrajet for idle mixture, just as a ball park?  I can adjust for maximum vacuum.

Thanks.

Yup, that's it.  Except start at 16 degrees BTDC, and back off by 2 degrees if it pings.  It shouldn't.

The reason it idles like crap now is that you have to change the vacuum advance port and the timing at the same time.  Changing the vacuum source only, your idle timing is way off now.