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Re: Holley 670 SA or 750 3310 on 340? [Re: Dart 340] #259572 03/20/09 04:27 PM 03/20/09 04:27 PM
Joined: Apr 2004 Posts: 1,396 Mass dgc333 pro stock
dgc333 pro stock Joined: Apr 2004 Posts: 1,396 Mass	Quote: Dave, Cam is 234 int and 244 exh at .050 and lift is .488 int and .510 the 3310 took a long time to run "acceptable" I just tried the 670 last evening and it seems to be pretty close. I still have a little trouble with idle being high enough the transfer slots are uncovered a little too much I think, but advancing the timing should help with that. I am only at 12 btdc and think I will go up to 16 or 18. 16-18 should be real close and it will certainly let you dial back the idle stop screw and most likely cover the transfer slots back up. Don't forget that you will likely need to limit the total mechanical on the other end to keep it in the 35-36 range. Dave Clement Pembroke, MA 03 PT Cruiser GT Turbo 99 Dakota SLT+ CC 4x4 68 Barracuda sport coupe http://home.comcast.net/~dgc333/

Re: Holley 670 SA or 750 3310 on 340? [Re: dgc333] #259573 03/20/09 04:46 PM 03/20/09 04:46 PM
Joined: Apr 2008 Posts: 1,195 Snowing in the north! D Dart 340 OP moparts member
Dart 340 OP moparts member D Joined: Apr 2008 Posts: 1,195 Snowing in the north!	Dave, I think I have a pretty much stock points disty with the exception of a pertronix kit. To I need to take it to a speed shop to limit timing or can I set it up myself?

Re: Holley 670 SA or 750 3310 on 340? [Re: Dart 340] #259574 03/20/09 09:35 PM 03/20/09 09:35 PM
Joined: Oct 2003 Posts: 7,506 Az Crizila master
Crizila master Joined: Oct 2003 Posts: 7,506 Az	You can do it yourself if your dampener is degreed or you have a cut-back timing light, but it's a pain, especially if your existing idle is up over 1000rpm and you are in to the mechanical advance already at idle. Most mopar point distributors had 12-13 mechanical advance degrees built in to them ( that would read 24 - 26 degrees at the crank - distributor turns 1/2 crank speed). If you want to set your initial at - lets say 18 crank degrees and you want a total of 36 degrees, you will have to limit the mechanical advance to 18 degrees ( 9 distributor degrees ). To do this you will have to limit the advance travel in the distributor by welding up part of the slot that the pins travel in. You can do it, but a lot of in and out and trial and error to get there - and you still have to address the rate of the curve by ploting it out at maybe every 500 rpm. I'd say find a shop with a distributor machine, give them the parameters you want, and let them have at it. They can also check your distributor for firing point accuracy -warn bushings, bent shaft and your vacuum advance curve if you are using one. Fastest 300

Re: Holley 670 SA or 750 3310 on 340? [Re: Crizila] #259575 03/20/09 10:25 PM 03/20/09 10:25 PM
Joined: Apr 2008 Posts: 1,195 Snowing in the north! D Dart 340 OP moparts member
Dart 340 OP moparts member D Joined: Apr 2008 Posts: 1,195 Snowing in the north!	Hmm so it sounds like I might be better if I disconnected the vacuum advance or used full manifold vacuum on it then....

Re: Holley 670 SA or 750 3310 on 340? [Re: Dart 340] #259576 03/21/09 10:57 AM 03/21/09 10:57 AM
Joined: Oct 2003 Posts: 7,506 Az Crizila master
Crizila master Joined: Oct 2003 Posts: 7,506 Az	If your distributor has a vacuum advance system om it, I would use it in your application. Although it has nothing to do with your problem. It is mainly there to improve fuel mileage at cruise by dumping in an additional 15 - 16" of vacuum ( on top of your mechanical advance )at light load ( cruise ) conditions to improve mileage. If you are running some boarder line temperature issues it can help there also. The minute you mash on the gas peddle, the vacuum advance system is out of the picture. Weather you use it or not is mostly a matter of preference. A lot of street performance guys don't use them and most race oriented distributors don't even have them. If you drive on the street alot, and it sounds as though you do, I would use vacuum advance. Fastest 300

Re: Holley 670 SA or 750 3310 on 340? [Re: Crizila] #259577 03/21/09 01:10 PM 03/21/09 01:10 PM
Joined: Jan 2003 Posts: 1,443 7 70duster340 pro stock
70duster340 pro stock 7 Joined: Jan 2003 Posts: 1,443	My 340 came with a 3310. It never ran well at all. It was always rich, and I had to remove the plugs at least once a week and clean and dry them to get it to start. I bought the 670SA, and it never ran so well! I haven't looked back since. My 3310 is still sitting in the garage. It needs a good rebuild, I believe. I don't believe I will ever reuse it, though. Maybe I sould sell it?

Re: Holley 670 SA or 750 3310 on 340? [Re: Dart 340] #259578 03/22/09 08:52 AM 03/22/09 08:52 AM
Joined: Apr 2004 Posts: 1,396 Mass dgc333 pro stock
dgc333 pro stock Joined: Apr 2004 Posts: 1,396 Mass	Quote: Dave, I think I have a pretty much stock points disty with the exception of a pertronix kit. To I need to take it to a speed shop to limit timing or can I set it up myself? If you are ambitious to take the distributor apart you can limit the advance yourself but either welding up the slots or using epoxy to shorten them. If you don't want to tear into it then having it done or buying an adjustable distributor like the Mopar Performance unit is the way to go. Find the initial advance your engine wants then subtract that from 35-36 to get the total mechanical advance number you are shooting for. Buy and $.39 protractor at the stationary sore and glue it to an old rotor (center of protractor over center of shaft). Tape an old coat hanger to the housing to use as a pointer. With the point plate and pertronix unit removed twist the rotor against the springs and measure the rotation. Double this number to get the crank degrees. Now remove the top half of the shaft with the slots and weld epoxy the outer end of the slot to reduce the length. Trial an error until you get the number you had come up with earlier. Dave Clement Pembroke, MA 03 PT Cruiser GT Turbo 99 Dakota SLT+ CC 4x4 68 Barracuda sport coupe http://home.comcast.net/~dgc333/

Re: Holley 670 SA or 750 3310 on 340? [Re: dgc333] #259579 03/22/09 11:41 AM 03/22/09 11:41 AM
Joined: Apr 2008 Posts: 1,195 Snowing in the north! D Dart 340 OP moparts member
Dart 340 OP moparts member D Joined: Apr 2008 Posts: 1,195 Snowing in the north!	I set the timing to 18 for idle yesterday with the 670 on the car. Set idle to 850 and adjusted mixture screws. Took her out and mashed on it and the car is running very good. No knock or ping from off the line or from higher speed even from 4th gear at say 2000 rpm. I will look into the disy curve also. Happy to have had weather break enough to drive her! I think the 670 will be staying on the 340. I cant really tell much of a higher rpm difference from the 3310 and it seems to give me zero bog or lag issues and throttle response if much better. Thanks all!

Re: Holley 670 SA or 750 3310 on 340? [Re: Dart 340] #259580 03/22/09 11:51 AM 03/22/09 11:51 AM
Joined: Jan 2003 Posts: 24,562 Brookeville, Md Mr.Yuck Not enough dumb comments...yet
Mr.Yuck Not enough dumb comments...yet Joined: Jan 2003 Posts: 24,562 Brookeville, Md	Sounds good. The only thing you'd notice w/ the smaller carb is a few mph in the 1/4.

Re: Holley 670 SA or 750 3310 on 340? [Re: Dart 340] #259581 03/22/09 12:02 PM 03/22/09 12:02 PM
Joined: Mar 2005 Posts: 3,138 Central NC gch master
gch master Joined: Mar 2005 Posts: 3,138 Central NC	Quote: I set the timing to 18 for idle yesterday with the 670 on the car. Set idle to 850 and adjusted mixture screws. Took her out and mashed on it and the car is running very good. No knock or ping from off the line or from higher speed even from 4th gear at say 2000 rpm. I will look into the disy curve also. Happy to have had weather break enough to drive her! I think the 670 will be staying on the 340. I cant really tell much of a higher rpm difference from the 3310 and it seems to give me zero bog or lag issues and throttle response if much better. Thanks all! Did you ever try bumping the timing up with the 750?May have improved it as well.

Re: Holley 670 SA or 750 3310 on 340? [Re: gch] #259582 03/22/09 12:11 PM 03/22/09 12:11 PM
Joined: Apr 2008 Posts: 1,195 Snowing in the north! D Dart 340 OP moparts member
Dart 340 OP moparts member D Joined: Apr 2008 Posts: 1,195 Snowing in the north!	I did try the timing higher last fall with the 750 and could never get rid of the weird hesitation even under no load. I am guessing it was the acc pump or cam, but never got it tweaked in just right. Maybe I will play with it some more. Now it's off the car I can pull the acc nozzle off and double check the shot size. I've done so much to this car in a year it's hard to keep track of it all. It was a non running trailered no dash mess, electrical mis wired nightmare. Now everything is working pretty darn well. Thanks for all the input guys, it's appreciated.

Re: Holley 670 SA or 750 3310 on 340? [Re: Mr.Yuck] #259583 03/22/09 09:56 PM 03/22/09 09:56 PM
Joined: Apr 2008 Posts: 1,195 Snowing in the north! D Dart 340 OP moparts member
Dart 340 OP moparts member D Joined: Apr 2008 Posts: 1,195 Snowing in the north!	I checked the squirters tonight and they look like 31's or even 34's. The 670 is surging a little so I might have to pull it and do a rebuild. And ideas on the 3310 for acc cam color and sizing etc before I wright her off completley?

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