Leftovers/junk 388 SBC
Moderator: Team
-
- Guru
- Posts: 2694
- Joined: Fri Jan 09, 2009 8:51 pm
- Location: Australia
Leftovers/junk 388 SBC
Dyno'd this collection of leftovers & junk yesterday & the bloody thing exceeded expectations by a good margin.
It's a 2 bolt 350 block, .060" over, ARP main studs, fresh torque plated bores, zero decked.
Rotating assembly is an old 400 crank ground to 350 mains, stock 350 rods with ARP bolts, cast dish tops, 400 balancer & flexplate.
Whole rotator came out of a worn out boat engine, would have been done in the 80's before 3.75" cranks were readily available.
I just cleaned it up & sized the rods.
Heads are shitter 400 castings, ported & angle milled back in the day.
They got k-lines, a fresh valve job, new budget 2.02/1.6" valves & the porting touched up.
Fresh engine pro springs with what look like old crane retainers.
They flowed in the low 240's.
Chambers ended up at 66cc, with the 12.5cc dish pistons compression ended up at 10:1.
Cam is a 252/256 on 108 SFT, rockers are old crane energiser 1.5 ratio.
Intake is some weird ass old weiand single plane, I match ported it & cleaned up runner entries.
Carb is an old 4779 750 with the choke milled off & a gasket kit thrown at it.
Oil pump is a second hand mellings stock replacement & sump is an unknown high volume that I had kicking around.
Ignition is an old locked hei & 6al.
Damn thing made 440hp @ 5800rpm & 436lb @ 4800rpm, held the power well up top & was overall well behaved.
We had a 2" super sucker style spacer on it, with no spacer it made 431hp.
I actually enjoy this kind of build, seeing what can be done with parts most guys would send to scrap!
It's a 2 bolt 350 block, .060" over, ARP main studs, fresh torque plated bores, zero decked.
Rotating assembly is an old 400 crank ground to 350 mains, stock 350 rods with ARP bolts, cast dish tops, 400 balancer & flexplate.
Whole rotator came out of a worn out boat engine, would have been done in the 80's before 3.75" cranks were readily available.
I just cleaned it up & sized the rods.
Heads are shitter 400 castings, ported & angle milled back in the day.
They got k-lines, a fresh valve job, new budget 2.02/1.6" valves & the porting touched up.
Fresh engine pro springs with what look like old crane retainers.
They flowed in the low 240's.
Chambers ended up at 66cc, with the 12.5cc dish pistons compression ended up at 10:1.
Cam is a 252/256 on 108 SFT, rockers are old crane energiser 1.5 ratio.
Intake is some weird ass old weiand single plane, I match ported it & cleaned up runner entries.
Carb is an old 4779 750 with the choke milled off & a gasket kit thrown at it.
Oil pump is a second hand mellings stock replacement & sump is an unknown high volume that I had kicking around.
Ignition is an old locked hei & 6al.
Damn thing made 440hp @ 5800rpm & 436lb @ 4800rpm, held the power well up top & was overall well behaved.
We had a 2" super sucker style spacer on it, with no spacer it made 431hp.
I actually enjoy this kind of build, seeing what can be done with parts most guys would send to scrap!
You do not have the required permissions to view the files attached to this post.
-
- Guru
- Posts: 4610
- Joined: Sun Sep 18, 2011 11:31 am
- Location: Heading for a bang up with Andromeda as we all are.
Re: Leftovers/junk 388 SBC
What we now call junk I would have been thrilled to have in my car fifty some odd years ago.
You can cut a man's tongue from his mouth, but that does not mean he’s a liar, it just shows that you fear the truth he might speak about you!
Re: Leftovers/junk 388 SBC
Great job! I love builds like these. Probably more than the high end stuff. What casting number are on the heads
Re: Leftovers/junk 388 SBC
KnightEngines wrote: ↑Thu Apr 04, 2024 8:24 pm Dyno'd this collection of leftovers & junk yesterday & the bloody thing exceeded expectations by a good margin.
It's a 2 bolt 350 block, .060" over, ARP main studs, fresh torque plated bores, zero decked.
Rotating assembly is an old 400 crank ground to 350 mains, stock 350 rods with ARP bolts, cast dish tops, 400 balancer & flexplate.
Whole rotator came out of a worn out boat engine, would have been done in the 80's before 3.75" cranks were readily available.
I just cleaned it up & sized the rods.
Heads are shitter 400 castings, ported & angle milled back in the day.
They got k-lines, a fresh valve job, new budget 2.02/1.6" valves & the porting touched up.
Fresh engine pro springs with what look like old crane retainers.
They flowed in the low 240's.
Chambers ended up at 66cc, with the 12.5cc dish pistons compression ended up at 10:1.
Cam is a 252/256 on 108 SFT, rockers are old crane energiser 1.5 ratio.
Intake is some weird ass old weiand single plane, I match ported it & cleaned up runner entries.
Carb is an old 4779 750 with the choke milled off & a gasket kit thrown at it.
Oil pump is a second hand mellings stock replacement & sump is an unknown high volume that I had kicking around.
Ignition is an old locked hei & 6al.
Damn thing made 440hp @ 5800rpm & 436lb @ 4800rpm, held the power well up top & was overall well behaved.
We had a 2" super sucker style spacer on it, with no spacer it made 431hp.
I actually enjoy this kind of build, seeing what can be done with parts most guys would send to scrap!
20240404_101835.jpg
20240404_171234.jpg
20240404_171240.jpg
"I actually enjoy this kind of build, seeing what can be done with parts most guys would send to scrap!"
Hmmmm starting to go my way LOL......we could use a guy like you!
Racing a NA NHRA stocker should be mandatory before any posting.
Re: Leftovers/junk 388 SBC
For true. What our OP did is only cost-effective if shop labor is removed from the equation and/or if the customer has a sentimental attachment to the build so he's not shopping for lower-than-crate cost.
Again, for true. Sixty years ago in another life, when I hung around Bo Field's shop, I remember sitting on a garage floor, hand washing parts in a pan of solvent; making last year's parts clean enough for Bobby Allison to use again. Ported stock iron heads. Inspecting stock rockers, balls and pushrods for bluing/galling was my important job.What we now call junk I would have been thrilled to have in my car fifty some odd years ago.
Jack Vines
Studebaker-Packard V8 Limited
Obsolete Engineering
Studebaker-Packard V8 Limited
Obsolete Engineering
Re: Leftovers/junk 388 SBC
This would be a good test engine to examine DV's 128 cam LSA formula. Couple cam swaps.
Also interesting to see what a high rise dual plane (rpm air gap) does on this one.
Also interesting to see what a high rise dual plane (rpm air gap) does on this one.
Re: Leftovers/junk 388 SBC
Question is: Does a calculated 105 deg LSA cam work better than this 108 LSA cam?
Can you get most of the way there by adjusting the 108 LSA cam intalled position and lash setting"
Can you get most of the way there by adjusting the 108 LSA cam intalled position and lash setting"
Re: Leftovers/junk 388 SBC
That's what a engine like that should make pretty easily. In the 80s we ran pavement late models . 357 inch ,unported 2.02 valve heads. Vic Jr intake and 500 holley 2 barrel on b37 fuel. Flat top rule hyd ft cam. If you didn't make 440-450 hp you did run up front ever.carb location and spacers and air cleaner tricks, you had to be on top of it all.I think 1992 was first yr we ever saw a tick over 500 hp. I just find it odd that stuff that ran mediocre in 70s and 80s that guys think it will mysteriously run better in 2024. It won't run any better in 2064!
Re: Leftovers/junk 388 SBC
In your dyno tests on this engine with a locked out HEI diz what ignition timing setting created the most torque. What ignition timing setting created the most HP?
How much difference?
How much difference?
Re: Leftovers/junk 388 SBC
To give our OP some slack, doesn't seem he's claiming to have found any magic; he was just giving himself props for putting together salvage parts and getting good baseline numbers out of it for cheap. Congrats.
Jack Vines
Studebaker-Packard V8 Limited
Obsolete Engineering
Studebaker-Packard V8 Limited
Obsolete Engineering
Re: Leftovers/junk 388 SBC
Understand fully .My point is that stuff was junk when it was new . It still is and always will be. He said it surpassed expected hp. Again that's what it should of made.This engine stuff is waaayyyy simple, certain volume and certain valve sizes will move so much air. It hasn't changed and it won't.
Re: Leftovers/junk 388 SBC
Exceeded expectations of guys at the shop (I'm guessing) and yer even with the flow numbers the heads would be expected to be the killer.KnightEngines wrote: ↑Thu Apr 04, 2024 8:24 pm Dyno'd this collection of leftovers & junk yesterday & the bloody thing exceeded expectations by a good margin.
Just needs a good set of heads and it will be taxing the bottom end.
Ignorance leads to confidence more often than knowledge does.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
-
- Guru
- Posts: 2694
- Joined: Fri Jan 09, 2009 8:51 pm
- Location: Australia