Thread: 73 vette with 454BB question...2 or 4 bolt mains?

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Hello all, recently acquired a 73 vette with a 454 BB, however I know it is not the #'s matching engine that it came with (have been told it is out of a 78 Suburban), Anyways my question is. were the original 73 454BB engines that came in Vets a 2 or 4 bolt main. I am looking for another 454 to rebuild and have ready to put in, and I am not too concerned about having the proper date code and stuff, but is it better to go with a 2 of 4 bolt, is there a certain year that is better than others. Also. I have heard that the Q-jets are better than Holleys on BB's, What is the general concensus on that one?

My opinion is that on a naturally aspirated street motor where engine speed is limited, a 4-bolt block is unnecessary.

I'll step out on a limb here and say that the Q-jet is probably the finest carburetor ever built. They're just like anything else in the realm of hot rodding, you have to learn how to set them up and tune them. Doug Roe was a GM engineer who probably knows more about them and how to get the most out of them than anybody else. Read his words of wisdom....
http://www.amazon.com/exec/obidos/tg...books&n=507846

Originally posted by techinspector1
My opinion is that on a naturally aspirated street motor where engine speed is limited, a 4-bolt block is unnecessary.

I'll step out on a limb here and say that the Q-jet is probably the finest carburetor ever built. They're just like anything else in the realm of hot rodding, you have to learn how to set them up and tune them. Doug Roe was a GM engineer who probably knows more about them and how to get the most out of them than anybody else. Read his words of wisdom....
http://www.amazon.com/exec/obidos/tg...books&n=507846

I will agree 100 % with what techinspector says.I had a 496 with a 2-bolt main and a stud kit.I was making 6.60 runs on this about every 3rd weekend and I never had any problems.I street drove this car whenever the weather was nice.After the 3 rd year I pulled it down for new rings,bearings,and valve springs.The caps still fit tight.I had to take a rubber mallet to get them off.

i have built drag engine two bolts mains. i know of pull trucks two mains that gets ran to 7500 rpm and many more two bolts i have built or help in more that 50 of them and in 20 years this is not a problem BUT CAPS MUST FIT IN THE REGISTER GOOD and if you are looking to make more than 700 hp get a better block bowtie or world or dart or donovan the bottom of the blocks are thicker and have thicker wall and make for a good blocks for hi hp and hi rpms pinning the stock caps is worth the works. why ?the caps is getting pulled down and the caps are iron and will fail at a point were a steel cap may be better to do this to or a better make of iron cap. world and donovan dose this to. so at apoint pinning a iron gm cap is not worth the effort studding the mains helps this is all you really need at the most.