My car is acting like the starter is weak after performing a 305 TPI to 350 TPI swap. When cranking it will not continuously spin and will instead sort of move a little bit then bog down and dim the dash lights then move a little bit more. What would cause this? It had not problems turning over my old 305. Is it just in need of adjustment with shims or does it need replaced? If it needs replaced is there a difference between 305 and 350 starters? Looking online they have a different part but same kW rating

 

Putting a starter that's barely adequate for a 305, on a 350.

Yes and no... they bolt up exactly the same, look exactly the same from the outside, but are different electrically on the inside.

Best solution is, forget about "305" and "350". Ditch the stooooopid Stone Age Delco direct-drive POS they've been using since the 50s and move at least up into the late 20th century, if not the 21st. Put a reduction-gear unit on it. Virtually ANY of them will blow your mind at how much better it works than that old Neanderthal crap.

The stock LT1 unit, or any of the various ones sold under any number of brand names that are actually Nippondenso or Hitachi motors with adapter plates, will put a big smile on your face.

 

I'll take another approach...took you some time to do the swap...battery may have dwindled some..

You also may have not cleaned all the connections well...battery plus/neg as well as block ground and starter ground/battery ground to block...as well as the cable ends.

Then charge the battery and see what happens.

 

Charge your battery, and also retard your timing some. You may have too much base timing in it so it's painfully hard to crank.

 

Battery should be nice and charged since it was charged before going in the car and I've been driving it for a while. Will definitely have to recheck timing and grounding though. I'll probably upgrade to a gear-reduction unit but I just replaced the solenoid on the old starter (old one's plastic cracked) so if I can get a few more months out of it at least it'd be nice.

 

The starter from the 305 doesent have enough power to turn a 350 efficiently. Need to switch the starter from one for a 305 to one specified for a 350

 

If it was a shim problem it would probably grind. I am betting it is a bad connection. I could not see them making a different starter for each motor. Maybe I am wrong as I have not worked much on 305s but why would chevy make a 305 and a 350 starter? When chevy needed more cranking power on high performance motors they used 168 tooth flex plates in place of 153 tooth most of the time. They did make high torque starters too but they used them on high performance stuff usually because they had high compression like the LT1. I am thinking they used the same starter on both motors and you have a bad connection.

 

Yeah that would make better sense, but I doknow that my starter in my 305 is different from my buddy's 350 starter, and they are both stock

 

Well I would resort to changing parts as your last resort. Maybe they are different but I would check every connection before you replace.

 

Also I think small block starters and big block are the same. So if it is designed for both a 350 should be no problem for your stock starter.

 

Chevy did make a lot of different starters but I don't know why.