Fred's 2375 Rebuild Thread Options

[friethmiller]

[A softball question for the Ninja and/or others]

This is the cam card that came with my 2357 engine, which was originally built by Rimco/Fat (long block) a few years ago. Can someone explain why with an intake/exhaust of 448, the lift was only set to 327 degrees? I'm about to rebuild my motor and a lot of focus will be directed at piston "deck clearance" and the valve train geometry that wasn't set correctly. Thanks.

[technicalninja]

It would be useful to have the shim measurements.
You should have two sets of four. A set should have same thickness in all.

Please check.

Might be possible to deck registers and achieve proper quench with a single shim.

Be handy to verify deck height of all 4.
If things are good, you'll be +/- .001

@cgnj I asked for skirt pics because of "short rod". I didn't see any evidence of bad thrust in the skirts he showed.
I didn't see them all, but it looks like the rod length works OK.

Sure! Each cylinder had two shims: one measuring .088 inches and another at .090 inches. I did do a rough deck height of .022 with just the .090 shim. I think that would mean, as it stands now, I would need a single shim of .108 to hit a .040 deck. I’ll double check everything in the morning for all 4 cylinders. Based on the fact that my pistons are already proud of the cylinders (w/o shims). If material is removed from the case registers, wouldn’t that increase the size of the shim needed? Wouldn’t reducing the crank size by 2-4mm makes more sense?

I mentioned earlier that I have a W block that I can use - assuming it checks out.

No skirt damage on any of these pistons.

Morning Update: With a 0.090 shim installed under each cylinder and using pvc pipes +washer/nuts holding everything down I get the following piston-deck clearances:

#1 = 0.023, #2 = 0.023, #3 = 0.024, #4 = 0.024

KICK ASS! you're with .001!

Too bad one of those shims wasn't bigger than .120; that's what I was hoping for!

Yes, cutting registers means thicker shims.

I thought I saw a link once to custom sized shims. You order them then wait type of stuff...

If I had your set up, I'd run it as-is (as long as I had valve clearance). I'd target 9.5 via minor combustion chamber massaging. I'd add ceramic coatings.

I believe I'd use the 9520 LN cam and their suggested valve springs (along with the cam junk I listed before).

Hastings rings, plateau honed, heads fly cut MINIMUM to achieve "perfect" jug to head seal. Registers cut flat (better to go minimum and go "bespoke" on the shim.)
I'd think about stronger head studs, probably include.

No FREAKING way I'd install an oil pump without the double O-rings around the body.
Those O-rings can eliminate air being sucked in on the entrance side. Critical in my book!

I'd expect to have to add additional oil cooling, but I'd look closely at the TR cooler kits that mount a Setrab in the back. I'd definitely use his T-stat set up with 215-degree T-stat. I would verify temps FIRST before adding oil cooling.

I'd provision carbs to the rich side and be conservative with timing. I'd be watching the CHT, AFR and if avaialble EGTs.

I'd really want some kind of knock sensor too! They made half-assed kits for detection and it's possible to make "Det-Cans" yourself. These are basically a microphone attached to the engine, running to amplified headphones, You REALLY can hear detonation!

I'd plug my det cans into the aux port on my modern radio head unit. Now the whole sound system is part of the det cans...

You would be SHOCKED at what you can hear with det cans. Loose sheet metal, bolts stand out. A rod knock sounds like King Kong is beating on it!

That 123 distributor (and the stock ignition system) is one of the weak points IMO.
I'd probably add an MS for the ignition system alone. Move up to a waste spark or COP from the start.
I like COP! (IMG:style_emoticons/default/devil.gif)

Having full ignition control IS 50% of the battle IMO.

And it will be easier to talk you into proper FI if it's already in the car!
(IMG:style_emoticons/default/ninja.gif)