Quote:
Originally Posted by F-BIRD'88
Just rebuild it 30 over with -5cc flat tops. get the block decked so you end up with a net
.040" quench clearance. EG: .028" gasket .012" deck. The heads are fine as is.
The cr will be 10:1 The GM LT4 Hot cam will work well.
There are many ways to juggle that and many gaskets to choose.
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Hi F-BIRD,
First about the background of my idea.. Concerning this engine's bottom end I'm kinda on a budget because I'm back in college now and I'd really like to finish this before summer. Doing machine work for a SBC here (in Europe) can be kinda troublesome. For balancing, I'd have to send the whole cranktrain out to UK, for instance. So that's how I got the idea to use a good used stock LT1 rotating assy. The -5cc flat tops you mentioned would prolly be in the same range as the LT1 (imho they are 6 or 7 cc). Do you have a pointer as to why I should make overboring an item on my To-Do list?
As for the deck, I'd likely have the machine shop work on it since it can be done local, I'm probably gonna have it decked a little to make it sharp straight or IOW a 'true plane'. So I'm not sure how much deck I will end up with. I was gonna make a heads milling/HG decision after putting the bottom end together.
Imho it all adds up.. New pistons and while I'm at it I could also get some other rods or otherwise I'd prolly need some ARP rod bolts. Add in the machine work and shipping.. An LT1 rotating assembly would be almost in the same range for strength and weight but is cheaper, and if I can find one local I could also save some on shipping, plus it doesn't need balancing. Good idea!?
Quote:
Originally Posted by F-BIRD'88
Do not under gear it. slowing down a cammed motor does not work well.
Cammed motors need rpm.
the Mini Ram is not a low rpm induction system. It wants rpm.
The exhaust system will make or break it.
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I'm gonna start with the 9bolt 3.27 I have in there now, but already have parts and plans for a 4.10 rear. Together with the later-LT1 T56 I have, that should give a decent but not too low geared drivetrain, the T56 being rather long in all gears. I was thinking that should be fine for something in the 3400 lbs range like a 3rdgen F-body?
I am aware that the MiniRam is, depending on displacement, more a mid- to high-rpm intake, but thanks all the same for reminding me
Exhaust system for now is a single 3" highflow Catco and mandrel-bent Hooker Aerochamber catback. Up front is a 'ported' 1 5/8" Hooker shorties system with a 3" Y-pipe.
Thanks a lot for your time and advice
P.S. I forgot to mention the cam I plan on using.. I already have a XR276HR, it's 276/281 (224/230 @.050") and .536/.544 w/ 1.6 RR, LSA 112 and IVC is 66. So a tad more than the LT4 HOT (218/228, .525/.525 @1.6RR).