is the ls1 a 60 or a 90? TIA

 

90

 

Yep, it's a 90 degree block. Pretty much all SBC's and BBC's are 90 degree blocks. The only 60 degree blocks that GM builds (that I know of??) are the V6's (2.8 / 3.1 / 3.4 / 3.8). I'm not sure about their odd-ball sized engines like the 3.0L or 3.3 (I think there's a 3.3?? ), and I think the 4.3L V6 is a 90 degree block. But the LS1/LT1/Gen-I SBC's are all 90 degree blocks.

 

lol, definetly 90 degree

 

thanks i was just wondering cause one of my friends asked and i didnt know for sure . . . and i dont know if it means anything to you but i just picked up a 305 tpi and its a 60 sbc v8, dont know if they all are like this or i just got hosed and didnt know what i was buying. maybe someone knows.

 

Who ever told you that a 305 TPI is a 60 degree engine is a complete moron. Only some V6s are 60 degrees, everything else is 90 degrees. The balance for a 60 degree engine would be very expensive.

What do you think 60 degrees means anyway? It is the angle apart from the right bank to the left bank. Place the engine's cylinder bores (either driver's side or passenger's side) parrallel to the floor, you see that the opposite ones are pointing straight up!

 

With offset throws of 20º I don't even think it would be possible to make a cross plane V8 at 60º work for any more than a few starter rotations, but then again, the Viper engine is offset at 18º for its 90º configuration.

 

By the way the 3.8 v6 is a 90

 

You're probably right. I've seen the others (2.8/3.1/3.4) all torn apart, but never a 3.8, so I was guessing on it.

Now were the old 348 and 409 Chevy big-blocks (from the old 60's Impalas) not wider than 90 degree blocks?? I remember watching a show on Speed Vision a long time ago about the 409 (also covered its predecessor the 348) and I remember it being a "wide" engine, and I think it was to do with the fact that the angle was greater than 90 degrees? Maybe not, but if someone knows for sure, that's kind of an interesting piece of "trivia".

 

Wide as in the actual physical dimensions, not a wide V angle. I don't think in the past 35 years or so anyone has made a non 90º V8, whether it be a flat or cross plane.