351 F-Truck block. Model as yet unknown, vehicle still in transit. Expect to be roller, 2 bolt.
T56 gearbox. Supposed to be good to 7,000rpm.
I will put in Eagle steel crank and rods (Eagle because their steel crank is cheaper than Scat and they seem to be decent) and will work to maximum of 7,000 at this stage. Std or .020 bore.
Heads - I have Dart Pro 1. Budget says tweak these unless there is total compelling reason to swap. Scorpion 1.6 rockers.
Induction - I think I can get a trickflow injection intake under the bonnet as long as it does not sit higher than Ford factory induction. Otherwise carb. Carb is cheaper as I don't have to buy the box , etc to run the injection. Only needs to be basic box as no electronic trickery is allowed in the chassis.
What numbers am I looking at and what do I need to do it?
Being in denial does not always mean you are in a river in Egypt.
Quality stock lifters can handle reasonable high revs (as Hybrid indicated) as long as the spring loads are not to high (which is a function of the camshaft lobe design). Having said that sustained high revs 7k+ is usually SR territory. An option I like to use though is the short travel HR lifters, which I have in my Mustang, as they can handle higher spring pressures without collapsing and are lighter so suited to high revs as discussed with lower maintenance of hydraulics. They are not cheap - quality never is.
Note: It is worth spending the budget on heads as the heads and cam combination is the real determiner of performance. The rest either holds it together or supports the main players.
Ok not as simple a question as it would first appear to answer.
Target 9.0:1 is easy for boost - with modern chamber design minimum 1bar (14.7psi) is safe you could target higher. Many are running 1 bar under 10.0:1 static this is on 98 fuels. If your running E85 11.0:1 no problem.
Chamber size depends on a number of factors; such as
1) Piston depth,
2) Gasket compressed thickness (Note: keeping quench around 40 thou as a priority).
3) Gasket bore size,
4) Piston valve reliefs size
5) Bore size (stroke as well but assuming 302 = 3 inch stroke).
1) Zero decked - piston top level with the deck
2) 40 thou compressed
3) Gasket bore size 4.1
4) Bore 4.030 (306 cid)
So normal setup using flat top pistons
5) -5cc valve reliefs
Chamber size for 9.0:1 is 64cc
Question though is it better to run flat top is a dished piston (if it is an option to gain you compression target)?
The dished piston, in theory, has more performance as it offers greater surface area for the combustion pressure to force the piston down giving it greater transfer of chemical to mechanical force.
So working out chamber size is a balance between chamber and piston dish (based on what is available).
So assuming 58cc chamber (as it is fairly common) a -11cc dish is needed.
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