Hypothetical 348 budget build options
- Thread starter Tom Kochtanek
- Start date
409/348 snout same size as sbc, BBC much larger won't fit the 348/409 timing cover
6.75" and 7" bbc balancers are available new (and were used on some stock big blocks). I used a stock one on my 427 and bought an aftermarket one from one of our members here a few months back. They aren't any more expensive than a comparable 8" balancer, but are harder to find the small stock ones used.
I think it wouldn't help save enough money to use the stock crank though. You still have to have the mains cut down to W size and have the throws cut down to clear the pan rails better so not cutting the snout isn't a huge savings.
On the other hand, if you were going to change to 4 bolt caps at the same time, then it would be good. You could use stock bbc 4 bolt caps and have the block align bored to bbc main size. That would make a factory bbc crank easier to fit with only cutting the throws down. It would also mean that bearings would be cheaper. I strongly considered going that route on my build.
I think it wouldn't help save enough money to use the stock crank though. You still have to have the mains cut down to W size and have the throws cut down to clear the pan rails better so not cutting the snout isn't a huge savings.
On the other hand, if you were going to change to 4 bolt caps at the same time, then it would be good. You could use stock bbc 4 bolt caps and have the block align bored to bbc main size. That would make a factory bbc crank easier to fit with only cutting the throws down. It would also mean that bearings would be cheaper. I strongly considered going that route on my build.
Right Don. I was just talking about the bbc balancer/custom timing cover issue. For a budget 348 build that makes good power and has some extra durability, I still feel like the 409 crank/Scat 6.385" rods/KB off the shelf pistons you are building is the way to go.What we're doing here is cblowing the tar out of the term budget.
I'm sure looking forward to seeing yours finished.
Ultimate budget 348' stock crank, stock or eddy heads, forged pistons, roller valve train. I bet I could get that combo into the 13's.
Ray,Given your expertice,and experiance with these engines,I'd be surprised if you didnt.I see no reason why a 348,the little roller cam like you sold me[230in-240ex@.050]Headers,10.5-11-1 compresion,690,583,or eddy heads,750 carb,eddy Performer rpm single4bbl.intake,lighter car,should Do mid to high 13's I'd think,once you got it tuned out.
Don or Ray, how would a 348 cube motor with Eddy heads do as a street motor? I am inclined to believe that the big valve heads would kill the low end torque. Chevy has been using the 1.94 intake valves on their ZZ4 crate motors from the very beginning.
I talked to a local engine builder recently and he was telling about an engine he put together per the customers wishes. They used the Eddy heads on a 348 and some old Stahl headers. They were plenty disappointed in the dyno numbers. Leo
I talked to a local engine builder recently and he was telling about an engine he put together per the customers wishes. They used the Eddy heads on a 348 and some old Stahl headers. They were plenty disappointed in the dyno numbers. LeoIt'd be a little "flat" on bottom,need a fairly deep gear[overdrive automatic for highway,with lock up convertor]and a small,modern cam,but doable .The lighter the car the better.A carb with annular boosters would be BIG help on the low end.I'd also think that 333's with bigger valves and some port work,or 817's would work too.
61 Bubble
Well Known Member
Tom, I myself think your on the right track as far as bang-for-the-buck using the 409 crank and BBc rod (stock or aftermarket) with a forged piston. (I know a bit biased seeing I have one, lol). I only see the 409 cranks getting CHEAPER as more and more stroke there 409's. So with that figure out some, next you need to do is figure out the induction system?
This is where it gets ALL FUZZY! See my thoughts are IF your popping for the Eddy or BWR alum. heads, then that changes what the thought of what the build is, and in return, changes the crank deal!!!! But if your using stock, cast OEM heads, 409 crank is the way and clean up the heads.
I look at the WHOLE package to get the best PACKAGE! That is what will give you the best running, happy engine with the performance to match!!! Your original question need to look at the whole engine at once and not "Forget about the top end and valve train for now, those are separate choices" as what your doing with the top end will directly effect the bottom end?
This is where it gets ALL FUZZY! See my thoughts are IF your popping for the Eddy or BWR alum. heads, then that changes what the thought of what the build is, and in return, changes the crank deal!!!! But if your using stock, cast OEM heads, 409 crank is the way and clean up the heads.
I look at the WHOLE package to get the best PACKAGE! That is what will give you the best running, happy engine with the performance to match!!! Your original question need to look at the whole engine at once and not "Forget about the top end and valve train for now, those are separate choices" as what your doing with the top end will directly effect the bottom end?
CDNpontiac409guy
Banned
Just my quick take on it...
"Eddy" or any other large port heads are not on a "budget". 3.76" or more stroke, is not on a budget.
This leaves up to about 388 cubic inches, with small port heads... "333" being BY FAR the best "budget" choice.
Any factory intake manifold is a collossal piece of sch!tt. Depending on how much cam you use, there are a couple modern intakes that will fit perfectly. Even with a strong performance effort, RPM will peak below 6500.
In the 2500-MAYBE 6500 range, with that short 3.25" or 3.50" stroke, as long as you use a proper light weight piston ( "budget" ?... ok, here, not so much ... about $1000 ), free factory stock BBC connecting rods ( right within budget ) will be just fine.
500+ HP available... with the ONLY costly part being lightened pistons.
"Eddy" or any other large port heads are not on a "budget". 3.76" or more stroke, is not on a budget.
This leaves up to about 388 cubic inches, with small port heads... "333" being BY FAR the best "budget" choice.
Any factory intake manifold is a collossal piece of sch!tt. Depending on how much cam you use, there are a couple modern intakes that will fit perfectly. Even with a strong performance effort, RPM will peak below 6500.
In the 2500-MAYBE 6500 range, with that short 3.25" or 3.50" stroke, as long as you use a proper light weight piston ( "budget" ?... ok, here, not so much ... about $1000 ), free factory stock BBC connecting rods ( right within budget ) will be just fine.
500+ HP available... with the ONLY costly part being lightened pistons.
I had the 348/379 heads and had the 2.06/1.72 valves installed on my .060" 348. I did a lot of blending under the seat on the intake and exhaust valve to remove the steps that the cutters left. I also tear dropped the shape of the valve boss on the intake and exhaust guides. I gasket matched and blended the runners in 1.25" on the intakes. I ran cast 9.5 pistons with a 218/224 @.050 hydro cam. The engine had three two's on top with Doug's Tri Y headers. In a 4200 lb 60 impala with 4:11's and a 350 tranny ran mid 14's. It would boil the hides out of the hole and light them up in 2nd gear. Power and throttle response out of the hole was eyeball flattening !
61 Bubble
Well Known Member
Umm, my "current 380 is much like this, just have to install the 3x2 on it and Ballanger header BUT 3.36 with a T10!!!! Might have to see where this goes.
61 Bubble
Well Known Member
Aubrey, Not sure if you recall, I just happen to have a 380 (I heard this guys know these W motors pretty good and knew what he was doing) much like this. So are you saying, that I kick apart this little motor, replace the pistons, BALANCE as I always do it anyway, and say some little cam like RL-248653D, clean up the heads and a Speed port 6000, should be north (possibly WELL north) of 500Hp?
I'd say one horse/ci is a good number to shoot for a nice street performance engine. A full race 388 with top of the line performance heads I doubt would see 500+ hp. And still be streetable. A 388 ci engine would have to make 1.3 hp per ci. To make 500 hp. Pretty hard to do with what's ready available for the W.
Yes John,Thats what he's saying!I for one believe it's entirely possible,although I'm far from an expert.My 380[if I can get it down here and ever get it done,has the budget[?] bottom end,a set of used ,lightly ported Bob Walla's[I bought them used from a fellow member here for about what a new set of Eddys would cost]and a Comp roller cam[also used from a fellow member] 110 center,4 degree advance,230 in-240ex@.050,and it will be topped off with a Speed-Sport 7000[not exactly budget,but I was going to have to buy a intake anyway],and I think that I'm going to make 500.I could be wrong.
If you don't make 500, I bet you'll be darn close Don. Compared to other choices I wouldn't say the Speed Port is a budget breaker. Especially if you look at it in a $$$ per HP gained way. People think nothing of paying $500 to $1000 for head porting to gain 50 horsepower (just throwing a number out there) but then think spending an extra few hundred on an intake which will add the same amount is a rip-off.
Looking at Aunrey's post reguarding the 6000 small port on his 409,His engine's a little bigger,suffers from some lack of ring seal,still makes 470 or so ,using small headers,nicely ported 333's with 2.07-1.72 valves,solid lift 'moderate"cam.Nice.My set up,smaller bore,but every thing fresh,camshaft very simular in lift and duration ,but's it's a mechanical roller,Big port heads,7000 intake,should equal or exceed with little increase in rpm.Maybe I'm totally out to lunch[possible,likely take your pick
]but I think it'll be ok for my first ever 'W" engine.
]but I think it'll be ok for my first ever 'W" engine.
CDNpontiac409guy
Banned
Thanks for the referrals, guys
... though I didn't mean just my intake.
If you need a torquey little engine, that's strong say 2000-5000 RPM, the Edelbrock Performer would be perfect choice. Remember that dyno test I did last year ? That performer, with the same carb, put another 10 ft lb torque and 35 HP on that 390 HP engine. Looking at it like was just pointed out, that's about $10-$12 per horsepower.
With a more aggressive build, I'm very confident that some at home porting on a set of "333" heads, with one size larger valves, would quite reasonably give you a 380-388 inch engine, that would be around 450 ft lb torque, and very near 500 HP.
Again, with the only "out of budget" part, being the high end forged pistons.
... though I didn't mean just my intake. If you need a torquey little engine, that's strong say 2000-5000 RPM, the Edelbrock Performer would be perfect choice. Remember that dyno test I did last year ? That performer, with the same carb, put another 10 ft lb torque and 35 HP on that 390 HP engine. Looking at it like was just pointed out, that's about $10-$12 per horsepower.
With a more aggressive build, I'm very confident that some at home porting on a set of "333" heads, with one size larger valves, would quite reasonably give you a 380-388 inch engine, that would be around 450 ft lb torque, and very near 500 HP.
Again, with the only "out of budget" part, being the high end forged pistons.