Over to Plan B...

[rt-man]

The '72 340 I bought for the '73 Satellite was torn down and found to have significant scoring in the bores due to it sitting around for years. Condensation took that puppy down.

So, my mechanic buddy has an LA 360 block and crank that's been sitting in an oiled bag since 2010. Bored .030 over; I imagine its a cast crank. Line bored, from what he recalls. He's going to examine the cylinders this weekend.

I'd like your opinions on this BUDGET build. Some parts are coming off the 340. Going in a heavy car ('73 SSP), cruiser, 904 with shift kit, 2,000 rpm stall converter, 3.55SG. 318/360 Performer intake, '69 HP exh manifolds, Summit 600cfm vacuum sec carb. Heads are '72 iron, valves opened to 2.02/1.60 valves, bowl ported.

- Hughes cam flat tappet hydraulic, 220/224 duration at .050
- Domed hypereutectic pistons, looking for 10.0 CR or better. New rings.
- new oil pan, new main bearings. 360 harmonic balancer and flexplate for the 904
- reuse the accessories, timing chain, etc

I may be leaving something out. Did I mention its a BUDGET build?

 

[dvw]

I removed my matching number 340 from my Challlenger. Built the 360 2 brl that was in my Volare. 9-1 , ported factory heads, [email protected] hyd roller, LD340, 650 Holley, headers, full exhaust and air cleaner in place. Been 12.70 w/3.55's. Runs on 87 octane. Cast crank strength? We are on year 6 with my sons turbo car. Its been 9.55@142, 3750lbs. Stock block, cast crank 360.
Doug

 

[rt-man]

I removed my matching number 340 from my Challlenger. Built the 360 2 brl that was in my Volare. 9-1 , ported factory heads, [email protected] hyd roller, LD340, 650 Holley, headers, full exhaust and air cleaner in place. Been 12.70 w/3.55's. Runs on 87 octane. Cast crank strength? We are on year 6 with my sons turbo car. Its been 9.55@142, 3750lbs. Stock block, cast crank 360.
Doug

Thanks, Doug, but what are your opinions about the build I'm relaying? Over at FABO, they are pooing on the domed pistons, aka too much compression. What pistons are in your 360 build, flat tops?

 

[PurpleBeeper]

"In general" 10:1 is a little high for an iron-head motor. However, if your cam has a lot of "overlap" (I didn't look up your cam), you might be OK if you run 93-octane only & don't advance the timing too much. 360's were flat tops stock...maybe 9:1 or 8.5:1 range... SMALL BLOCK GUYS CHIME IN PLEASE!

 

[furyus]

Did i read you were going to re use a timing chain? Not where you want to save a buck. Imo, make sure the short block is built with quality. You can always swap heads, intake, carb, etc, if you want to later. There's some really smart guys on Fabo. Yellow rose is one I'd listen to.

 

[IQ52]

Thanks, Doug, but what are your opinions about the build I'm relaying? Over at FABO, they are pooing on the domed pistons, aka too much compression. What pistons are in your 360 build, flat tops?

Define 'Domed hypereutectic pistons". Do you have a part number?
Keith Black has a solid dome -1.2cc part number KB190 or a solid dome -11.2cc part number KB191. Then there is the quench head/quench dome 2.8cc part number KB373.

 

[rt-man]

Define 'Domed hypereutectic pistons". Do you have a part number?
Keith Black has a solid dome -1.2cc part number KB190 or a solid dome -11.2cc part number KB191. Then there is the quench head/quench dome 2.8cc part number KB373.

Thanks. No part numbers or make determined yet. I'm looking for inputs and recommendations.

 

[IQ52]

I was just curious. With your desires.....i.e. budget, cam, cylinder head and the piston dome question, this appears to be another 'bag of cats' that I have no desire to jump into. Others can have at it.

 

[wyrmrider]

OP wrote in his first post
"Domed hypereutectic pistons, looking for 10.0 CR or better. New rings.'
no idea which piston he was referring to
that said
(w/ 9.599 crank c/L to deck
1.675 compression ht
i'd be looking at the
KB232 .050 quench dome 18cc dish
not
KB373 .085 quench dome 2.8cc high comp
KB362 step dish 19.4cc (I think this is the one for the closed chamber heads)
there used to be another one and I found it in the discontinued section
KB 372 18.3cc step dish 24.06 does not look like it has a quench dome

also saw
Cast 3204.030 QOH 288 Chrysler 360 Chrysler .070 dish 1.576 comp ht
.020 deeper dish than 1279 1.576 ch .050 dish standard 360)
1279 would be same as sealed power suggestion
8.5 to 1 $11.41 would be down the hole .100
360 Truck piston- shows how without quench ch had to be dropped more for HD use

also some 3222 in std to .060 $16.23
1.605 ch rectangular head recess .080 10cc
so this one would be down .070 in the hole

There is an Icon forged piston 9.6cc dish (and valve reliefs) not quench step
5 cc flat top no quench step= for closed chamber heads to work
-11.2cc solid dome will fit edelbrock head no quench dome

 

[dvw]

My motor was built years ago when TRW flat tops were the only common available piston. It has a LOT of deck cut and head milling without quench. Though we still run it that way today there are way better options. With iron heads over 10-1 can be tough with pump gas.
Doug

 

[rt-man]

Cam card

 

[wyrmrider]

probably a good cam if the duration matches the torque curve- rpm range
you want
can't tell if it works with your compression and gears without the seat timing
hint
match it up with Howards lobe list- see if there is a fit on lift and .050 if so you can get the .006