Recommended head for Nakasil 10.5:1

[mspenard]

What is a recommended head for use with BOE's Nakasil 10.5:1 block? Moreover, what are all my options (sector111's head vs Jim's ... ?) and the differences?

[addertooth]

Key question, which supercharger or how many pounds of boost turbo?

[tommyc]

Call phil at boe or jim clayton the will give you all info you need. I believe jim has a beautiful head for sale


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[Deja Vu]

MWR has a nice one that is reasonably priced as well.

[mspenard]

Originally Posted by addertooth

Key question, which supercharger or how many pounds of boost turbo?

I'm also looking at the REV400. I'm a newbie here, trying to learn as much as I can about what is available and what is good practice. If anyone has anything to add or words of advice I'm all ears. Thanks.

[mspenard]

Originally Posted by Deja Vu

MWR has a nice one that is reasonably priced as well.

But what are the differences and pro v cons between Phil's, Jim's, Sector111's and MWR's? And what are the weak points with the stock head?

[addertooth]

Jim Clayton's heads are highly regarded here. On something like a rev400 kit they might net you another 20hp (assuming other elements of your system are set up right). To get the most of the rev400 you will have to upgrade transmission and clutch. You need to look up engine internals as well. Google "2zz-ge glass engine" to get details on the parts which need beefing up.

[elise/europa]

My personal opinion: stock with good valves like Ferrea and slithly heavier spring (not Ferrea), and don't rev too high the engine, around 8200. Based on my experience, reving high with moderate spring can cause valve break on the retainer clip zone. I think that heavier spring can just be worst because of the added side load. Of course, you can port the head if you think that your rev400 still don't have enought power.

[mspenard]

Originally Posted by addertooth

Jim Clayton's heads are highly regarded here. On something like a rev400 kit they might net you another 20hp (assuming other elements of your system are set up right). To get the most of the rev400 you will have to upgrade transmission and clutch. You need to look up engine internals as well. Google "2zz-ge glass engine" to get details on the parts which need beefing up.

Right, the glass-engine reputation of the 2ZZ, that is why I was looking at Phil's Nakasil block. His webpage is unclear to me, however. It states new pistons, but what about the connecting rods and crank???

I also have a Fidanza flywheel and new clutch in mind of course. And from what I've read knife-edging the crank isn't worth the bother because it'll likely require annual bearing maintenance (although I assume that advice is contingent on someone with sufficient experience or not balancing it).

[Apex_in_sno]

Originally Posted by mspenard

Right, the glass-engine reputation of the 2ZZ, that is why I was looking at Phil's Nakasil block. His webpage is unclear to me, however. It states new pistons, but what about the connecting rods and crank???

I also have a Fidanza flywheel and new clutch in mind of course. And from what I've read knife-edging the crank isn't worth the bother because it'll likely require annual bearing maintenance (although I assume that advice is contingent on someone with sufficient experience or not balancing it).

Nothing to worry about with the rods and crank, they're both beefey, no body's bent eather of these that I know of.

[elise/europa]

In regards of the crank knife edged, they are harder on the main bearing caused by sectional unbalance. For drag, yes; for road race for fun, no; for serious racing where every x.1 seconds count, maybe.

In regards of the clutch, the ACT will be able to take the torque, but when I was using it, I was breaking the pusher plate casing one a year. Now, I am uising a expensive OS Gikken clutch, trouble free and it work great, but with a metalic noise at idle when the clutch is pressed; you can like or not. I am doing track and street without hard start from 0.