jeffcj

iTrader: (3)

Now that I have some cash to spend (again) I'm back to working on my 88.

After a major setback (cracked block) I'm ready to go.

I just purchased a short block assembly. Since I'm spending money, I went with this 383 short block.

Now I'm thinking the heads and/or cam I have won't work.
601 casting heads/58cc/2.02 intake, 1.60, pocket ported
Comp Cams hyd roller cam XR276HR-10 .502/.510



Thoughts anyone? Worst case I'll be selling off some parts and buying something else. It happens I guess.



383 CHEVY SHORT BLOCK 383 S-4
• Scat Cast steel crankshaft - 3.750" Stroke
• Scat 6" Forged I-beam rods
• MAHLE forged pistons
• Moly file fit rings
• 350 GM 4 bolt block painted color of your choice
• Dura-bond cam bearings
• Block plug kit
• King high performance bearings

Labor
• All parts hand cleaned
• Block sonic checked for thickness
• Block pressure tested @40 psi
• Block stroker clearanced
• Block square decked w/BHJ fixturing
• Aligned hone mains
• Bored and honed w/torque plates
• All clearances checked to the nearest .0001”
• Rotating assembly balanced - Internal
• Engine blueprinted w/specs sheet on file
• Short block fully assembled

five7kid

iTrader: (14)

Compression is your issue. The 601's have small chambers; if your pistons aren't dished, CR will be sky-high.

jeffcj

iTrader: (3)

It's a custom build, so I can request dish pistons. I had been running the numbers on that myself. Flat top pistons with those heads would be downright scary.

My other concern is whether or not the block has provisions for my roller cam. I'd hate to give that up, but if I have to I can pick up a flat tappet cam and E-Bay this one.

Apeiron

If the picture on the eBay ad can be trusted, it's a roller block. Best to contact them and make sure, of course.

jeffcj

iTrader: (3)

I confirmed with the vendor today that it is a roller block. They're also using -16cc dish pistons.

Here is their response.
"I used a 16cc dish piston. This will give you approx. 10.5:1 compression with your 58 cc head and a 9cc gasket volume. This will allow you to use premium pump gas (91/92 octane)."

discostu

Since when can you use 10.5:1 with Iron heads on pump gas?
You should request a 25cc dish piston which will give you about 9.5:1.

EDIT:
You'll actually need a 30cc dish, because 601 heads are 53cc from the factory, not 58cc. Unless you measured them at some point in time.

Apeiron

"Pump gas" means different things to different people. To some, it's 87 octane.

jeffcj

iTrader: (3)

Yeah, my car has never ran on 87 Octane.. Probably never will now, lol.

So, I've been thinking about this (I know, a dangerous thing.)

Originally my project here was supposed to be a TPI--> Carb swap and a mild rebuild. What I ended up with (or will end up with) is the aforementioned 383 short block.

The heads (which I purchased when I was still working on that "mild" rebuild) are 601 casting "305" heads.

Here's the info from the spec sheet:

Machined with 16 bronze thick wall guides
3 ANGLE Valve job / Pocket Ported under valve seats
3/8 screw in studs and guide plates installed
2.02 swirl polished intake valves
1.60 swirl polished exhaust valves
Hardened exhaust seats for unleaded fuel
Hardened valve keepers
Assembled with new .550 lift valve springs

Now I'm concerned that these heads won't flow well enough to keep up with the 383. Do I need to be looking into getting rid of these things and finding something else?