Engine spec

I think I have narrowed things down.
A Dart aluminum 8.2 block.
Callies crank
oliver rods
Diamond pistons.
Beehive springs Titanium retainers
Shaft rockers.
4 Barrel carb.


The dilema is this.
either a 4.125 bore and 3,2 crank and solid rollers for a 347 and an ability to rev sweetly to 7k+
or the the same with hydualics and 6500 redline.
Or the same with a 3.4 crank so 363with hydralics and similar power to the solids.

What keeps me away from the 363 is I love a sweet smooth rever and the 363 seems like a bit of a long stroker, some say with good balanacing and light internals it will make no difference.

What keeps me concerned about the 347 with solids is having to adjust valves every 500 miles, which for me would be at least 2x per year. But on the other hand it would eb a sweet rever with a broad powerband which is ideal on track.

Or am I just overhtinking it and is 6500 rpm plenty on a V8.

I come froma Lotus so lightweight and revs is next to godlyness, had a chevy 383 which was rough, so I really wnat to focus on a smooth rever. In any event I know a broad powerband with adjustability through revs is ideal on track where the car will spoend 80+% of the time. Question is would a 447 with hydralics be more than enough, or am I being overly concerned about valve adjustments.

Some say its more liek every 2 K miles.?
 

Mike Pass

Supporter
If you want to rev it then you need an internal balance and the lightest reciprocating components.
Cheers
Mike
 
4.125 bore & 3.25" stroke, use a cam with tight lash specs, do the lifter bore mod for oiling,use yella terra or similar paired shaft type rockers with adjustment at pushrod end, get your rocker geometry correct and probably most important work out your cold lash setting by doing an actual calculation for cold versus hot settings on your engine combination, then you can check lash cold in a much more relaxed & convenient manner.
Forget the 363 version, your building a sports car, not a tow truck.
 
You're overdoing it a bit I think.

I have just a modest spec 347 (4.03 bore, 3.4 stroke) and it works just fine. Revs to 7000 on the track all the time and is happy doing so. Power is still climbing at 7000, so I could rev it harder if I was brave and spend more on bottom end. Scat cast crank, I beam rods and KB forged pistons. 6000 km on it now, and that is just driving to events, racing then driving home. No cruising to speak of, it's not fun to drive slowly...

Having said that, I think maybe a 3.25 crank and 4.125 bore is better. I could do that having a Boss block. Maybe when it needs a rebuild.

Oh, I run a Lunati solid roller cam, comp cams lifters and Yella Terra Platinum shaft rockers. I don't check the lash hardly at all, though probably should. Bigger cam going in soon, once I get power and lights into my new shed. Hope springs don't mind it too much (668 thou lift!).
 
You're overdoing it a bit I think.

I have just a modest spec 347 (4.03 bore, 3.4 stroke) and it works just fine. Revs to 7000 on the track all the time and is happy doing so. Power is still climbing at 7000, so I could rev it harder if I was brave and spend more on bottom end. Scat cast crank, I beam rods and KB forged pistons. 6000 km on it now, and that is just driving to events, racing then driving home. No cruising to speak of, it's not fun to drive slowly...

Having said that, I think maybe a 3.25 crank and 4.125 bore is better. I could do that having a Boss block. Maybe when it needs a rebuild.

Oh, I run a Lunati solid roller cam, comp cams lifters and Yella Terra Platinum shaft rockers. I don't check the lash hardly at all, though probably should. Bigger cam going in soon, once I get power and lights into my new shed. Hope springs don't mind it too much (668 thou lift!).
Could you give me an idea what it means when you say you dont check the lash hardley at all, is that once ayear every 200 miles etc.

Yeah I am overdoing it a bit, I imagine the rings cylinder bores will be the first to go in terms of anything serious. The crank rods etc dont need to be stronger than the scat stuff, its juts a matter of using lighter components for smoothenss and revability, plus that extra insurance.

I am hoping that once it goes together besides regular fluid changes and maybe yearly valve adjustemnts I can do 10 or so track days and maybe 1000 or so street miles per year for many years without having to do more.
 
What's wrong with going to an anti-pump up hydraulic roller? Lunati has them...think others too. Supposed to be good to 7000 RPM and more.
 
If you must have a 363 use the 3.4 crank, a set of 5.62" rods ( Holden-Scat make em ) in 2.125 or 2.100 brg size, & a set of custom $$$$ pistons made with 0.875" pin height, then you will have a similar rod ratio to the 3.25/5.4 combo and also keep most of the piston in the bore at BDC, perfect a 'Truck' that revs like a sports car...:)
 
Sean, your planned usage is similar to what I've been doing with mine since 2010. I do around 12 events per year and check tappets maybe once per year, 2 oil changes per year. Pay attention to your oiling sytem. I run a Canton road race sump and accusump. It needs the accsump on some corners!

Scat I beam rods, cast crank and KB pistons are light enough, but of course you can go much better and spend more too. Your choice.

I chose solid camshaft because I didn't want to be wondering if my lifters are going to limit the fun (revs).

Good luck with it all.

PS - Youtube search my channel (200MPHGT40) and you'll get an idea of what my motor goes through.
 
Sean, your planned usage is similar to what I've been doing with mine since 2010. I do around 12 events per year and check tappets maybe once per year, 2 oil changes per year. Pay attention to your oiling sytem. I run a Canton road race sump and accusump. It needs the accsump on some corners!

Scat I beam rods, cast crank and KB pistons are light enough, but of course you can go much better and spend more too. Your choice.

I chose solid camshaft because I didn't want to be wondering if my lifters are going to limit the fun (revs).

Good luck with it all.

PS - Youtube search my channel (200MPHGT40) and you'll get an idea of what my motor goes through.

Belive it or not, but my concern also is that for the track, all that power may be ovekill.
 
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