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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: st3vomettler on November 07, 2015, 03:43:17 pm

Title: Heads
Post by: st3vomettler on November 07, 2015, 03:43:17 pm
How can you tell if a set of 305 heads have been worked on?
Title: Re: Heads
Post by: SkinnyG on November 07, 2015, 04:52:40 pm
If the intake valves are 1.94 or bigger, and/or if the combustion chamber is smoothed considerably, and/or if the ports are smoothed considerably.

305 heads on a 305 are fine.  305 heads on a 350 are not ideal, but mine were free, needed ZERO machining, and I ported the snot out of them.
Title: Re: Heads
Post by: st3vomettler on November 07, 2015, 05:08:20 pm
The intake valve is bigger then the ones in my 882 350 heads and every port on the 305 is the same size as the 350 heads
Title: Re: Heads
Post by: SkinnyG on November 07, 2015, 07:43:24 pm
What's the casting number?
Title: Re: Heads
Post by: st3vomettler on November 07, 2015, 08:21:19 pm
The 305 head casting is 14022601
Title: Re: Heads
Post by: SkinnyG on November 07, 2015, 08:30:42 pm
Interesting.  Those come up as HO 305 heads - the best 305 heads to use.  Small chambers raise the compression, but shroud the valves.  Lots of people swear by them, even more swear at them.  If they are in good shape - run 'em! 

Any evidence of porting in the bowls?
Title: Re: Heads
Post by: st3vomettler on November 07, 2015, 08:35:09 pm
As far as I can tell there's not any but the pistons are dished
Title: Re: Heads
Post by: SkinnyG on November 07, 2015, 10:57:04 pm
Dished pistons and those heads, depending on the gasket should be around 10:1 compression.
Title: Re: Heads
Post by: st3vomettler on November 08, 2015, 06:32:26 am
Ok and on the head it looks like the cc has been homed out some for the intake valve but I was wondering if a torker 2 intake would be to much for it.
Title: Re: Heads
Post by: st3vomettler on November 08, 2015, 12:26:44 pm
I'm trying to figure out whether or not to use a torker 2 intake or go with the stock intake. I measures the intake on both the stock and the torker and the stock intake has bigger intake ports than the torker one.
Title: Re: Heads
Post by: enaberif on November 10, 2015, 06:47:21 am
if you want to put a new intake on look for a performer. they are proven to be good and reliable.
Title: Re: Heads
Post by: st3vomettler on November 10, 2015, 09:29:12 am
Ok I was just wondering out of the two I have which one it the best one to use
Title: Re: Heads
Post by: SkinnyG on November 10, 2015, 09:51:54 am
The specs on the Torker II say 2500-6500.

Unless you have a rowdy cam and deep gears to keep the engine up there, I'd suggest the stock intake. Though I'm sure you could find a used Performer for cheap.
Title: Re: Heads
Post by: st3vomettler on November 10, 2015, 01:45:20 pm
Ok I'll go with the stock intake for now but should I use the spread bore carb that's already on it or a edelbrock 600cfm that I have?
Title: Re: Heads
Post by: SkinnyG on November 10, 2015, 06:44:04 pm
Use whatever runs the best.

I'm a big fan of Rochesters (they are very tuneable).  Others are fond of Holley's, or Edelbrock's (Carter's).  Try each and see what works.

Wait - the Edelbrock is a square bore, isn't it?  Run the Q-Jet.
Title: Re: Heads
Post by: st3vomettler on November 10, 2015, 07:19:32 pm
It's a Autozone brand carb that I bought for my old 77 350.
Title: Re: Heads
Post by: st3vomettler on November 10, 2015, 07:21:34 pm
I have the adaptor to run the edelbrock carb.
Title: Re: Heads
Post by: SkinnyG on November 10, 2015, 09:44:00 pm
You would probably have better performance with the Q-jet and without the adapter, but that's just my opinion. 

If the Q-jet sucks, swap carbs and use the adapter.
Title: Re: Heads
Post by: st3vomettler on November 10, 2015, 10:09:53 pm
It works on it but for some reason the back two barrels want kick in like it's saposed to and I rebuilt it to
Title: Re: Heads
Post by: SkinnyG on November 10, 2015, 11:43:21 pm
Just learn how to tune it (grin).  Lots of stuff online, and excellent books on the Q-jet (Cliff Ruggles book is good).  A properly setup Q-Jet is an awesome thing, but few people want to learn them well enough to set them up properly.

Title: Re: Heads
Post by: st3vomettler on November 11, 2015, 06:07:33 am
Ok but it's not a qjet its a autoline carb from autozone
Title: Re: Heads
Post by: blazer74 on November 11, 2015, 07:08:28 am
Autoline is a rebuilder, could still be  a Qjet.
Title: Re: Heads
Post by: Dan75k20 on November 11, 2015, 10:03:44 am
Snap a photo of the carb. 305 ho heads were on z28 camaros in the 80s alot of circle track guys run them on 350s
Title: Re: Heads
Post by: st3vomettler on November 11, 2015, 11:45:17 am
Ok I will When I get home and Would you happen to now what causes it to hesitate?
Title: Re: Heads
Post by: blazer74 on November 11, 2015, 06:53:38 pm

Just learn how to tune it (grin).  Lots of stuff online, and excellent books on the Q-jet (Cliff Ruggles book is good).  A properly setup Q-Jet is an awesome thing, but few people want to learn them well enough to set them up properly.

^this.       Lots of variables, depending on when.
History of carb, did it run good before.
Off idle stumble, cruise stumble, ?
Title: Re: Heads
Post by: st3vomettler on November 11, 2015, 07:09:57 pm
Off idle and it done it since I bought it for my old 350
Title: Re: Heads
Post by: enaberif on November 11, 2015, 07:12:40 pm
Any off the shelf carb you buy for ANY vehicle is NEVER a bolt on and go setup. You will need to tweak and tune that carb to run right.
Title: Re: Heads
Post by: st3vomettler on November 11, 2015, 07:20:39 pm
I've tried and tried but I still can't get it to run right I have even rebuilt it but when I put my edelbrock 1406 carb on it it ran great but it keeps flooding out
Title: Re: Heads
Post by: enaberif on November 11, 2015, 08:45:26 pm
I've tried and tried but I still can't get it to run right I have even rebuilt it but when I put my edelbrock 1406 carb on it it ran great but it keeps flooding out

1406 needs a fuel regulator or you'll flood it.
Title: Re: Heads
Post by: blazer74 on November 11, 2015, 11:46:58 pm
Hard to say what the rebuilder did to it. They try to make them generic so they will fit more applications.
Stumble off idle could be lean or rich. Improper pump shot, over rich or lean idle circuit. If you can disconnect the acc pump linkage and blip the throttle in neutral/park and see if the stumble gets better or worse. Watch the linkage doesn't get hung up tho.,
Title: Re: Heads
Post by: 1979mmx350 on November 12, 2015, 02:09:49 am
Ok I'll go with the stock intake for now but should I use the spread bore carb that's already on it or a edelbrock 600cfm that I have?
I threw on an Edelbrock 1406 last week and it was running cherry til I blew a rod earlier today. Actually, could any of you recommend a solid cam replacement?
Title: Re: Heads
Post by: st3vomettler on November 12, 2015, 06:04:03 am
Ok any suggestion on what the fuel pressure should be for it
Title: Re: Heads
Post by: enaberif on November 12, 2015, 05:49:41 pm
Ok any suggestion on what the fuel pressure should be for it

4-5psi MAX anything more and you'll just flood the carb.

Ok I'll go with the stock intake for now but should I use the spread bore carb that's already on it or a edelbrock 600cfm that I have?
I threw on an Edelbrock 1406 last week and it was running cherry til I blew a rod earlier today. Actually, could any of you recommend a solid cam replacement?

depending on what you want 12-300-4 is highly regarded if you want something for torque.
Title: Re: Heads
Post by: st3vomettler on November 12, 2015, 06:25:53 pm
Ok thank you would anyone happen to now what the valve lash is saposed to be set for
Title: Re: Heads
Post by: st3vomettler on November 14, 2015, 06:51:17 pm
It is a qjet and the number on it is 17058213 2457 bjb
Title: Re: Heads
Post by: 1979mmx350 on November 14, 2015, 10:54:32 pm
Ok any suggestion on what the fuel pressure should be for it

4-5psi MAX anything more and you'll just flood the carb.

Ok I'll go with the stock intake for now but should I use the spread bore carb that's already on it or a edelbrock 600cfm that I have?
I threw on an Edelbrock 1406 last week and it was running cherry til I blew a rod earlier today. Actually, could any of you recommend a solid cam replacement?

depending on what you want 12-300-4 is highly regarded if you want something for torque.
Whoops meant to say crank actually.