JRoy91RS

Ok, I think I may have found one reason why I'm having such trouble getting my car to run. My question is three-fold:

1)The castings on my heads say 10110810. The part number runs parallel to the firewall with the heads installed. Some sources on this page say they are 305 TBI heads. I've looked other places on the net. Some concur, but most other places say they are 93-up 350 TBI heads. WHAT the HECK are they?

2) The reason why I ask is that a well-reputed machine shop built this engine, and told me that it was a 355. If these really are 305 heads, how can I tell if my block is 350 or 305 without pulling the heads? (I.E. where is the part number on the block??) I'm beginning to wonder if I got ripped off.

3) If these are 350 heads, are they worth anything at all? Can they be worked to flow decently, or would it be more cost effective to buy a set of assembled Vortecs (I know of a place where I can get assembled Vortecs for 350 a set!!)
3a) Is it safe to run a cam with my lift (see sig.) on the 10110810 heads? What about the Vortecs? I know that people say the Vortecs are good UP To .480 lift, but what about .480 on intake and exhaust? Am I pushing it?

Thank you guys as always for helping me with the tough ones!!

James

Keith5

On www.mortec.com the heads show up as this:

10110810...91-up...350..........Gen. 1


http://www.mortec.com/castnum.htm

On the side of the block on the bottom you should be able to see 3 numbers cast into the block. Those are the last 3 numbers of the casting number. That should be enough to see if your block is a 350 or 305.

JRoy91RS

Yeah, I saw that page, too. I was wondering, though, because I searched the archives here and the consensus was that they are 305 heads. Do you know anything about them?

Keith5

All I know is what is on mortec.

JRoy91RS

Anyone else know anything about these heads?

Tas

ask the tech guys at www.sdpc2000.com . They're pretty helpful.

Audiman

I dont know if this guy will help you but you can try him. Scott at the parts depot in Bellevue,WA. Brooks Chevrolet. Ask him to run the cast numbers under the V.C. thru the computer.

gilbert011

If I may add my two cents here. I am a hobby engine builder. I came across these heads 10110810 about 2 weeks ago for pretty much free (20.00). I also has the same question as to what the heck they were 305 or 350 heads. Here is what I found out after 2 weeks every day of asking around and asking local machine shop in my area (West Texas).

The casting was reused for both 305 and 350. I asked how to tell and the most common answer I got was: if you have them removed measure the intake valve, if they are 305's they will have a 1.84 measurement, and if they are 350's they will have 1.94 measurement. Another way to tell is the "meat" or material between the chambers should be just under 0.5" (half an inch). Well I did just that yesterday afternoon with a new digital caliper I just bought. I got lucky and based on the info I got mine are 350 centerbolt heads. If you cannot remove or do not have your heads removed, sorry. In my area there was two mechanics (not engine builders) that said that sometimes you can tell a 305 casting and 350 casting by the way the casting number is situated on the head. 350 casting is vertical to the sides of the cylinder head. I would not put too much stock in this method but it is something to look at. Hope I made this clear as mud as we say here in these parts.

woody80z28

iTrader: (2)

I found these heads on a stock 94 1-ton truck 350 last month. They have sodium-filled exhaust valves and valve rotators. Ports & chambers are about the same as a typical 193 swirl port, with just a little bit less of a swirl ramp.

Dixiemudder4x4

I don't have any input on what heads you have but I can tell you from experience the standard head from a 350 tbd motor will not clear .480 lift. Bit with a little machining you can do it. The guides are too tall and need cut down. If the head is off and spring removed you can measure the difference between full open and closed. I had mine machined to .500 make sure to give at least .020 extra. I believe springs are rated that way. But I would have gone with the vortec heads if they were available.

Fast355

iTrader: (2)

~.450 is where the ports stall on these heads anyway, can't see the logic to cut them down and go for more lift. I did once, made good power, but lost alot of torque in the process. I swapped a stock LT1 cam with 1.6:1 rockers and that is about .490" lift, never touched anything other than the springs and retainers.

hatemail72

we still dont have a answer I am looking at buying a used engine for $350. It is a runnng 350 block with computer is it worth keeping these heads. what have you found out