Just purchased a 1961 348 truck engine #3798962. Is there a good menu out there that can be done to increase the horse power by an additional 100hp. Suggestions please.
100 HP comes in a bottle
348 responds to hop ups like any other Chevy
Nice intake and modern 4 bbl will add 50hp
Some small diameter headers will add 35-50 hp
Nice 2.5 inch exhaust and you are there
do not add anything too big and unnecessary
409 powered 61 Poncho
best time 9.06@ 148
63 Pariesienne sport coupe (The Big GTO), black, maroon interior, 409 4 speed; former owner of a 59 El Camino, 63 Corvette SWC, 62 Chev Bel Air SC.
Mahone Bay, NS Still not old enough to need an automatic
You might want to upgrade camshaft....when doing intake and exhaust mods... Showcars/Dr.409 would be a good consultant on camshafts......They sell Isky cams....as I recall........and Ed Iskedarian......was grinding cams for W motors......when they were current in Nascar...... Also have a set of larger 1pc valves ...in stainless....for a reasonable price...
.....formerly 64 Custom Sport.....now appearing as MoboMac
Fender dice,furry skirts and flames...just say NO...
These guys really know how to do a ROCK video...
im starting to recommend roller cams, I know they are more expensive, but the extra power is worth it, and if a dinasour like me can evolve from flat tappet.
Magician40 wrote:Just watched that Youtube video and that car was a 4dr. Back doors have been welded shut and filled in. Brian
Just watched that Youtube video and that car was a 4dr. Back doors have been welded shut and filled in. Brian
Actually maybe fiberglass, I know he said he had some glass work done to it, it was just a car to put a motor in when he had it. He had it for sale (sold) for $10,000, the motor was easily worth that. Ronnie has built 20 or 30 or more great 409's and is an old drag racer.
DonSSDD wrote:Magician40 wrote:Just watched that Youtube video and that car was a 4dr. Back doors have been welded shut and filled in. Brian Actually maybe fiberglass, I know he said he had some glass work done to it, it was just a car to put a motor in when he had it. He had it for sale (sold) for $10,000, the motor was easily worth that. Ronnie has built 20 or 30 or more great 409's and is an old drag racer.
Yeah, I had an engine that Ronnie built in my 55 Chevy.
It was a stroked 409 (476ci) that was built for bracket racing.
My best 1/4 mile ET with that engine was 10.26
The truck engines are a good starting point, they're very similar to the passenger car engines.
It would be no problem to build a nice 350 hp engine but these days, with the weak Canadian dollar, parts get a little expensive.
Show Cars is as good a place as any to get parts. They show engine rebuild kits on this page... http://www.dr409.com/03_Engine-Int_03.html
They can also give you advise and put together a package where everything will work together.
The main difference is that the truck engines have low compression.
All 348 blocks have a notch at the top of the cylinder but some truck blocks have an extra notch added to further reduce the compression. Your #962 block should have a single notch but it was right around 1961 that they did away with the second notch so it's possible that it has two. Either way you can get enough compression but the single notch blocks are the preferred setup.
The heads are fine for 350 hp or so but they'll probably have small valves so if you're rebuilding them, it would be good to put in bigger valves. Many people install 2.06 int. 1.72 ext. valves in the truck heads. (that's the size on valves used on the 340 hp 409)
There are also valve rotators under the exhaust valve springs on truck heads. You'll want to get rid of those and install new springs.
I'm not familiar with the casting numbers of your exhaust manifolds but all 348's had similar looking manifolds. Most had 2" outlets but some had 2 1/2" outlets. (the 350 hp 348 had 2 1/2" outlets)
I think your intake manifold is the same as the one used on the 305 hp 348 in 1961. It would be OK but it's probably set up for the smaller WCFB sized carb, so it would be nice to get a new aluminum Edelbrock intake.