70 big block header help
 

ive got a 70 monte carlo and i have a new 454 crate engine and i did a 4 speed swap and im have problems finding a set of header that will fit a 4 speed set-up. anybody have a 70 4 speed and have any header advice on what works?

i dont personally have a 70 bbc monte but heres a set that will fit a 4spd bbc chevelle. to my knowledge under the body they are identical. obviously you have to find a set that will work with your combe. summit and jegs both have a pretty good search filter. good luck.
Summit Racing SUM-G9010 - Summit Racing® Headers - Application - SummitRacing.com

My BB 70 Monte has an automatic but I don't run headers. When I first bought this car years ago when it had the original 400 sb in it, it had headers and I hated them. I couldn't keep them tight, I burned up I don't know how many sets of plug wires from the heat and not from the wires laying on the headers. Spark plug changes took about four hours and I couldn't keep starters in it because the heat was killing them. A BB puts out more heat anyway so I would hate to see what goes bad with one running headers. I swapped out to stock exhaust manifolds on the SB and was a lot happier.

I kept the stock exhaust manifolds on the 396 currently in the car and am happy with them.

I'm sure you can find headers that would work. Look for headers that fit a 70 Chevelle with the BB and four speed and it should work.

Wayne

thats odd that you had header problems. it could have been a poorly made set, or off brand? i've always run headers and haven't encountered the problems you did with exception to the starter issue. the factory starters are pretty big and sit fairly close so heat soak could be an issue, but they do sell shields or one can be made. not to mention mini starters. on them coming loose i think its all dependent on the hardware that you use. i've had leaks before, but that was from running cheap gaskets. spark plug changes are a pain depending on what header brand you go with, but an open end, jointed extension, patience, and pulling them in a particular order makes it a snap.

I don't know what brand they were since they were on the car when I bought it but they were a hassle. Back then they didn't have the lock type header bolts setup that kept the bolts from backing out. I also had many exhaust leaks. I just know my experience with mine will keep me from running them on anything else.

Wayne

i wouldnt let that experience turn you off the whole header thing. you never know what headers were on the car and they could have been for a different application. a quality header company like headmen and hookers fitments are usually fairly good and if you use a good gasket like earls you should be good. the power gain for the price is usually pretty good.

I may try them again someday but right now I'm happy with the stock exhaust manifolds although one of the ears that the bolt goes through is broke off on one side. No exhaust leak though.

Wayne

theyre way easier to do when youre doing an engine build. kind of a pain with the motor in the car, on the ground with the starter in the way. definitely a worth while mod. what year is your 396?

My 396 is a 1969 that was in a 69 Caprice I had. It was originally a 2 barrel, the only year the 396 came that way. This engine was built for torque and does not have the hi performance heads. The heads actually say "truck" on them. It still has plenty of power.

Wayne

yeah i can believe it. the 396 was never really a super high performance motor lacking cubes, but it made up for its lack of size with brutal torque. the solid lifter versions were stout though.