Parts I purchased today for my 383 budget build any suggestions

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73dart360

73dart360

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TODAYS PURCHASE
I purchased 68 383 block with all of these parts im trying to figure out what compression can somebody take a look and give me any suggestions
1968 383 block and Main caps .30 over- Fresh Bore- Steel crank -Good
Sealed power Cast Pistons Part #366NP .030 New reconditioned LY rods and bolts
Edelbrock performer RPM Intake -New
Indy Aero 452 heads 219-1.88 valves- New
Cloyes double roller timing chain- New
Edelbrock 750 cfm Carb- New
stock lifters-Old
Melling High volume oil pump-New
High Volume water pump-New
aluminum water pump housing -New
Comp Cam 21-242-4 and Lifters-New - This cam will not work with my 323 gears it needs a 3000-3500 stall and 391 gears
Valley tray-New


THE PARTS ALREADY ON THE CAR

15" WHEELS Big Bolt Pattern
Front disc Brakes
8.25 with 323 gears
26" tire
I am staying with 323 gears
The cam that came with all of these parts is a comp cams- 21-242-4 This Cam needs a 3000-3500 stall with a 391 gear
I spoke with Comp Cams they suggested this cam Extreme Energy 268-H i told them i thought the heads might be 9-1 or 9.5-1 i am not sure ?

PARTS NEEDED
stock big block valve covers
power steering brackets
Mopar electric ignition and distributor
727 torque flite
kick down linkage
schumacher motor mounts and torque strap
 
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The combo you are about to put together will be low on torque and not very street friendly. the comp 292 duration cam needs more compression than the 7.5 the piston and head combo you put together. the 268 would be a better choice. if indeed the 452 heads have 219 and 188 valves you can not use them without notching the bore. they probably are equipped with 214 and 181 valves and should be fine.
 
With that choice of piston, .084 thou. below the deck, that will net you 7.9 to 1 compression with a undecked block and using a .039 thick head gasket.
 
with piston that deep in the hole. a steel shim gasket would be a better choice if the deck surface is square/ prepped.
 
if you can order pistons, keith black 400 hypers would net 9.5 - 10.1 comp depending on head cc's.
 
Speed pro L2315 is about .070 taller and with a steel shim gasket should get you in the 9.2 to 1 range. They do not have valve reliefs so not much room for high lift cams. KB also has a flat top and a dome both with valve reliefs. Look at summits website.
 
That's better. KB400 comp height 1.908 would be .020 below the deck (factory unaltered spec)
 
without working the heads, a camshaft over .500 lift would be nonproductive.
 
The rods have LY on them, I haven't looked at a 383 - 400 rod lately but as I remember the RB - 440 motors had the LY on the rods. The B - 361 - 383 - 400 motors use a shorter rod, the pin and bearing are the same. If I am correct it would put your piston above the deck on your block.....Thanks Webby.
 
WEBBY said:
The rods have LY on them, I haven't looked at a 383 - 400 rod lately but as I remember the RB - 440 motors had the LY on the rods. The B - 361 - 383 - 400 motors use a shorter rod, the pin and bearing are the same. If I am correct it would put your piston above the deck on your block.....Thanks Webby.
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You are correct as you can tell im not mechanically inclined ,Thank god for the people on Fabo
 
have the machinist check the assembly of the heads locks, a bowl port and gasket match would be a great mod.
 
73dart360 said:
should i send the heads out to be bowl ported ,i would not know who to take them to In Fort Lauderdale
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that I can't answer, it's not cheap. and depending on your performance needs may not be necessary. if you are staying with 3.23 gear you will be limited with camshaft selection.
 
Please stop buying parts until you have known measurements of what you already have. LY rods are 6.760 CTC length. Stock 383/400 B motor rods are 6.358(ish) CTC.

I'm going to bet the block will require between 010 and 020 to clean up square. The last two 400 blocks I did cleaned up at 9.965 deck height. This is to your advantage. If the rods are stock 6.358 length, the KB400 is a good choice as long as the rings are set using the proper gap, which is larger for the hyper explosive pistons. S/F.....Ken M
 
EchoSixMike said:
Please stop buying parts until you have known measurements of what you already have. LY rods are 6.760 CTC length. Stock 383/400 B motor rods are 6.358(ish) CTC.

I'm going to bet the block will require between 010 and 020 to clean up square. The last two 400 blocks I did cleaned up at 9.965 deck height. This is to your advantage. If the rods are stock 6.358 length, the KB400 is a good choice as long as the rings are set using the proper gap, which is larger for the hyper explosive pistons. S/F.....Ken M
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they are the stock 383 rods
 
the KB 400s will net you anywhere between 9:1 depending on where they are in relation to the deck height what gasket you use and how the heads cc out. Just for argument sake:

88cc chambers, which is typical for open chamber heads
020 below the deck
.040x4.40 gasket (typical)
~ 9.2:1

same heads/gaskets, 010 below the deck
~9.4:1

disclaimer: None of those numbers are exact; if you want exact numbers, you'll need to break out the burette and measure with the pistons in the block. There's a thread in the how to section from krazykuda on how to do it.

I'm kinda curious how the heads measure out...
 
I'm running that 268 duration cam in a throw together engine for 20 years now. 906 heads with factory 72 400 intake TQ, plenty of torque and go.
 
I just got a call from the machine shop ,The 383 needs Bore He thinks i should build the 400 block i also have -Is there any way to keep stock stroke and get 400-450 HP out of a 400 I have all of the parts listed above ,Including the 383 steel crank
 
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