I'm planning on putting together a 406 with parts I have picked up dirt cheap.

I got a shortblock with block damage (deck, deep gouge) for $100.

It has TRW L-2352 .030" forged pistons in great shape. They are an .083" dish, and according to two TRW catalogs are for a 377 destroker using 5.7" rods.

The crank is definitely a 400, casting number ends in 529, I have measured the stroke and it's 3.75"

I was told short rods must hae been used to make this combo work, I can't find any ID marks on them and haven't had them measured.

My questions are as follows:

1. WIll I end up with an abysmally low CR with these dished slugs, used in conjunction with my 700 Edelbrock Performer RPM heads (Barely used, $500 bucks)?

2. What kind of deck clearance should I shoot for or avoid?

I will be using this with my Wieand Action Plus intake, HEI, Jet Q-jet, and small tube headers off my 355, it will go in my 3200lb S10 with 2200 stall and 3.73's

Cam recomendations?

Eric

 

I forgot to add I have picked up a 2 bolt core block for $150 and the guy will hot tank it, magnaflux, align hone, install cam bearings, bore and torque plate hone it for an additional $275 bucks.

Eric

 

You got some good advice so far. Even though it's a brain teaser between the piston and rods you can use 377 de-stroker pistons with a full-stroke 3.75" 400 crank assuming you also use the 400-style "shortie" rods (5.56" vs. 5.7" for more typical 350 rods). That gets the deck height roughly right.

You'll want to shoot for an actual MEASURED deck clearance with that combo of .025" or less.

Your compression ratio will depend heavily on your deck height, head gasket thickness and combustion chamber volume. I don't think you should have too much trouble getting compression where you want it. The usual problem with a big cube motor is getting it LOW enough. So starting with dished pistons you should be able to get it where you want it pretty easy.

Do you have specs on the piston dish volume (cc) and combustion chamber size of the heads you will use? I could calculate it for you with that additional info.

 

The heads are 70 cc, the "700" was a typo. Actually, I typed that post THREE times and each time I hit "preview post" it kicked me back to the "You are not logged in" so the post was lost! The last time I typed it I hit "ENTER" before that happened again so I didn't get to proof read it.

The pistons are an .083" dish per the TRW catalog.

The scrap block had .025" deck clearance.

All the pistons have been balanced to the rods from what I can see with them having drill marks underneath and being stamped with the rod numbers.

Eric

 

Your compression ratio should be 9.6:1 with a stock deck height block (.025") and a felpro 400 gasket.

it would be 10.17:1 if you "0deck the block"

I would use a Crane Powermax H278-2 cam in your application.

specs are 278/290 .467"/.494" 222/234@.050 114LSA.

This is a nice street cam for a 400like yours

Lots of power to 5500+rpm. Just right for your 400 with a 2200stall and 3.73's

should be pretty good on gas too.