suggestions on a 273/318 build

[ragtopfury]

I'm putting the cart before the horse seeing how we just got the car stripped to nothing but a rolling empty shell and are rebuilding the floor boards, but I'm always thinking ahead.

So........... my son's 65 has it's original 273 (froze up but may be savable). Would like to maintain the originality of the motor if we can save it - with some light mods. If not, I have a 69 318 we can use. I also have a few parts lying around that I'd like to use to keep his costs down as much as possible against his high school/allowance budget as he's not getting a part time job until after next summer.

Sooooooo.... Here is a list of what I have to work with:

the original complete basic 273
a complete untouched 69 318
an older single plane edelbrock intake
a double plane edelbrock intake (model escapes me at the moment) off a 360
a pair of freshly redone 71 360 heads - no porting has been done
stock hydralic 340 cam/lifters from Mopar Perf
a little Carter AFB - have to verify the cfm
a carter AVS - have to verify the cfm
the original 904
3.23 gears in either rear we decide to go with - both are sure-grip. one is 7-1/4, the other is 8-3/4 (almost certain we're going with the big one here)
with either engine definitely double roller chain, hv oil pump, upgraded pump shaft, keeping the factory exhaust manifolds. Going to have a larger Y pipe built and dumped into a single 2" or 2.5" single exhaust just to be different.

If we determine it is savable. I know the 273 will need bored seeing how it is froze up The 318 may or may not need a bore job - it ran great before I removed it 15 years ago.

I'd like to build him a nice little motor without overdoing it for a 1st time driver/1st time car. Something that sounds good, runs good, 100% streetable, yet with enough go that I can drive it like I stole it and show him what he better not get caught doing when he blows the doors of his friend's 94 Bronco... LOL LOL... and so it begins

Other than stuffing/topping the original 318 in my Fury with 340 6pack, I've not built a motor beyond stock... suggestions based on what I have to work with are appreciated. I realize a basic/stock rebuild is the answer his mother wants to hear, we all know how that goes........

 

[rumblefish360]

First, decide which engine you want to build. The 318, IMO, is the one to go with because pistons are cheaper with more verity. Egge makes 273 pistons, there cast, inexpensive.

With the 3.23 gears, the dual plane Edelbrock is the better bet. I like the AVS over a AFB myself. The adjustable air door is a winner for me. Use the AFB flat rod covers and rod over the 3 step AVS and raised rod cover units for greater rod selection.

The 360 heads are fine for aggressive builds and just OK for mild ones. I'd rather ported 318 heads. Since money is an issue, the 360 heads are probably getting the nod for use. The amount of head cc is going to keep the ratio down a bit. You might want to think about milling them down a bit.

This may create a problem with the intake, which is solved by milling that down as well. Have the machinist do both at the same time for a great fit.


IF that MP Purple cam is a exact 340 cam, toss it and use the replacement 340 cam for more duration and better performance. Also, use a stock oil pump, a HV only robs power from the engine. There is no call for a HV pump at this point and seldom is there a call for one.

Dual exhaust would be much better.

Just tell the wife it is a stock rebuild with a bolt on part or two for the cool factor and minimal HP gain. (It's not exactly a lie.)

 

[66fs]

The best cheapest build would be

untouched 69 318
a double plane edelbrock intake (model escapes me at the moment) off a 360
a pair of freshly redone 71 360 heads - no porting has been done
stock hydralic 340 cam/lifters from Mopar Perf
a carter AVS - have to verify the cfm

Mill the J heads .020 on block side and .019 on intake side. That should get you back to the same cc as the 318 heads. Then you can use any 340/360 intake. Use the AVS as is, unless it is way off. I doubt it, but then follow Rumblefish's advice above. Rebuild it and adjust the air valve loose till it bogs then tighten till the bog goes away, maybe 1/4 turn if I remember right. New gaskets and seals. Optional New rod bearings and a windage tray. You will need a crank adapter to use the 273 auto trans. Adjust bands, drain convertor and replace filter and fluid.


sell the 7 1/4 sure-grip. They go for big money. 65 273 heads have the odd angle intake bolts.

 

[rumblefish360]

a double plane edelbrock intake (model escapes me at the moment) off a 360

The 2 dual plane Edelbrock intakes I'd consider for a 318 would be the LD4B or the Performer. There is also a dual quad intake floating around made by Edelbrock.