quote Originally posted by Will: Lol... good luck! Especially with a light weight clutch, driveline loss won't be a huge factor, but you'll still need 320-330 HP at the crank to hit 300 at the wheels. Basically, you're going to need three things to hit that number: -Outstanding port work. The "port" being the entire intake flow tract from the plenum to the valve... the engine doesn't care whether that's in the cylinder head or the manifold -Solid roller cam. Yeah yeah yeah, people like flat tappet cams for inexplicable reasons. Rollers are just better. Period. -High compression. 10:1 is not high compression. With those big three in line and other details dealt with appropriately for the build, you'll hit the number. That's pretty much the max that iron heads are capable of, though. Getting power out of an engine with mediocre head flow has always required getting everything other aspect of the build on point. If you're using shelf GM pistons, that's going to be difficult, as GM never built pistons to run high compression with iron heads. The iron head pistons will run 12:1 or thereabouts with the smaller chambered aluminum heads. I guess there could be an application with adaptable pistons, but then you're likely not to have the right wrist pin size, so then you have to bush the rods... etc. In my experience, buying what the build needs is a better value than trying to adapt something that's close. If you haven't been using gapless top rings... you should be.

Off the shelf parts for me is whatever I have on MY shelves.
I've been developing the Supernatural engines for a while now and along with that the experimental parts, specially on the valvetrain. Camshaft technology has come a long way since the 70's so I don't need a roller camshaft. Lobe design in a flat tapped can almost match the roller cams.
Yes, the roller cam has the advantage of friction over the flat tapped but the latter has an advantage on the roller on weight. Roller lifters are much heavier than the solid flat tapped. So, with the flat tapped I can run less spring pressure and have more throttle response due to the lower moment of inertia of the lighter lifters.
You'd be surprised if you see how many experimental camshafts I have sitting on my shelves, from different engines. For the 60* I have about 4 and the cam for the 3XX is has bee on the shelf, also one of those went to my friend Blacktree.

As far as the compression my 3.4 is 10.85 not 10.00. The pistons for the 3XX are stock from an engine and the static compression will be 11.65.1.
Unfortunately, for the 60* there is not much aftermarket like for other engines like SBC or LS, so that's where creativity comes into play and it seems that has been lost with this generation of hot rodders, specially the ones that think they know it all because they graduated from Google University.
Its very easy to purchase a part and slap it on an engine and call yourself an engine builder but that is no fun for me. The fun part is get to your goal with whatever you have available and if you can make a couple of parts yourself its even better, the sense of accomplishemt is much better than just following the crowd.

I know I can make a 60* turbo and make 600-800hp with no problem but power is not what I'm looking for, balance is. My goal with this engine is to match or get very close to the same power-to-weight ratio of a Porsche 911 GT3 and the Acura NSX 2018 with whatever parts are available to me. I know these cars can drive themselves due to the amount of technology in them and that can make the owners of these cars feel like race car drivers. Me, I like it the old school way, raw, loud and difficult to tame. It's more fun to build your machine and drive your machine and develop a relationship with it, It'll give you years of satisfaction even though you fail a couple of times along the way, just don't give up!

So, for all of you that have a unique Fiero, weather is a V8, V6, L4 or whatever other transplant , I admire your tenacity and take my hat off you because you are unique people, just likeme!

[This message has been edited by La fiera (edited 01-04-2018).]

quote Originally posted by La fiera: Off the shelf parts for me is whatever I have on MY shelves.

I think there's a big difference between that and what most people consider "off the shelf".

BTW, you have a PM.

[This message has been edited by Blacktree (edited 01-04-2018).]

quote Originally posted by La fiera: Lobe design in a flat tapped can almost match the roller cams.

"Almost"

quote Originally posted by La fiera: Yes, the roller cam has the advantage of friction over the flat tapped but the latter has an advantage on the roller on weight. Roller lifters are much heavier than the solid flat tapped. So, with the flat tapped I can run less spring pressure and have more throttle response due to the lower moment of inertia of the lighter lifters.

Moment of Inetria applies to rotating components, not reciprocating components. What you're talking about has nothing to do with MoI.
What's important in a valvetrain is the frictional power required to turn the cam at a given RPM. That's related to the contact load between the cam and lifter times the coefficient of friction between the two parts. The work that goes in to compressing the spring is returned on the closing side of the lobe... so only the frictional component matters. The contact load is driven by both inertial and spring forces, so weight does matter... however...

Yeah, valvetrain mass is important, but that's more from the point of view of achieving enough stiffness in the pushrods and rocker arms to accurately reproduce valve motion against a spring stiff enough to control valve motion at maximum design RPM. Lighter components allow less sping, but the whole tradeoff is more about achieving a stiff valvetrain than minimizing weight. Don't forget that the most serious rocker arms in the industry are STEEL and not aluminum.

Slightly heavier lifters require greater spring load, but the rollers reduce the friction to the extent that the frictional power required to turn to cam goes DOWN with a roller valvetrain.
In every racing class where it's allowed, builders run roller cams. The extra lifter weight is worth it.

quote Originally posted by La fiera: You'd be surprised if you see how many experimental camshafts I have sitting on my shelves, from different engines.

I don't think I would. An avid builder will have experimental parts around.
*Most* of the time those are from failed experiments, though.

quote Originally posted by La fiera: The pistons for the 3XX are stock from an engine and the static compression will be 11.65.1.

That's getting into the ballpark... I haven't built an iron head V6, so I'm less familiar with how much compression they can run on pump gas vice aluminum head engines. I was thinking 12.5, but that would probably be a race gas engine if using iron heads.
Have you tried Singh grooves with high compression?

[This message has been edited by Will (edited 01-07-2018).]