Im looking at possibly getting a zz4 shortblock and building it up from there. Which heads would go best on it to start me off?

AFR 195cc SBC Street Cylinder Head
195cc SBC Street Head Part Numbers
CNC Ported Pairs of Cylinder Heads Complete With Parts and Ready to Install


CNC Street Ported Heads
195cc Street Heads, Straight Plug w/heat riser, 74cc 1036*
195cc Street Heads, Straight Plug w/heat riser, 68cc 1034*
195cc Street Heads, L98 Angle Plug w/heat riser, 74cc 1038*
195cc Street Heads, L98 Angle Plug w/heat riser, 68cc 1040*


Whats the diff between having angle plugs or straight?

 

It really depends what you want out of the entire set-up. You have to match a cam and heads and intkae together? How much power do you want to make?

 

Yeah sorry, i porbably should have said that before. Im looking to make between 400 - 450 hp/trq. Anywhere in there would be good. I just wanna break the 400 barrier. It wil be carbed for sure. Im gussing 750 cfm?Can you recomend a good cam that will meet my needs?Also an intake. I do want to keep everything under a 2 1/2" cowl.

 

Well, carbed I am not to sure, but here is my setup running 450/450.

Super Ram (1000cfm TB)
Balanced and blueprinted 355
Forged internals
LT4 hot cam
1.6 RR's
AFR 195's (208/282 flow)
manley valves

Not sure with a carb, but the super ram uses 1000CFM and with that engine It needs every bit of it.

 

Well, to start with, ZZ4 heads are 58cc. So even with the smaller chamber AFRs, your CR will take a massive nosedive, unless you have them mill them down.

Angle plugs put the spark plug in a better place in the chamber for combustion. Plus, they fit better with most headers (not all though, I hear, though I've never seen such a thing).

Looks to me like you need the last one; and find out how much they'll charge to bring them down to 54-56 cc.

You'll need more cam than the ZZ4 cam to make 400 HP. GM's answer is the LT4 HOT cam, which will get you there but just barely. It's not really enough cam to fully use the heads' potential, but with FI, you have to make that compromise. You don't with a carb. There's lots of better ones in the aftermarket. I'd suggest a Comp XR282HR with 1.6 rockers.

Get the heads set up from AFR for .600" lift. That cam and those rockers will give you .544" lift, and since AFR uses weenie K-Motion springs, I wouldn't dare use what they supply at anywhere near their "spec". Or, just change the springs out for something decent once you get the heads.

400 HP with a carb doesn't require any 1000 CFM. A 750 Holley or Demon, with a Edelbrock RPM or Air Gap, would be about perfect.

 

why would i want less than the 68cc AFR's. I always thought that more would be better. Yes, i am going carb. Would you recoment an alternate set of heads that would work well right out the box? I would rater not buy a brand new set just to replace the springs befor i put the heads on the engine.

 

68cc is the chamber volume. It's not a matter of "less" or "more"; it's what determines the compression ratio. The CR of the ZZ4 is already pretty low, and it has 58cc heads on it; if you put heads with larger chambers on it, the CR will be even lower. The lower the CR the harder it will be to make that kind of power. That's why you need heads with no larger than 58cc, and prefereably smaller; like 54-56cc.

AFAIK there are no heads offered that come from their mfr at this chamber volume. Any heads you get, you will have to have milled. Ask AFR about milling yours to that volume. I's guess that to lose 12cc of chamber volume you'd have to cut about .070" off of the deck, straight-milling them; somewhat less angle-milling. It's alot easier to get an intake cut to match if you can cut the heads straight, it's one less variable you have to work with.

If you want heads to come out of the box that are perfectly matched to your combo, then put them back in the box after you get them matched, so they can come out of the box ready to go. You're not usually going to be able to just slap a bunch of stuff together just as it comes off the shelf with no further thought or planning or finesse or effort and get the best possible results. This is hot-rodding, not appliance operating. Every combo is unique. In order to get the most out of your parts, you have to match each of them as perfectly as possible to the others for the intended application. That's why the guys you see that spend cubic $$$$ on their street motors especially aren't always the fastest ones: there's more to this than just bolting stuff together.

AFR can probably do this for you, for a nominal fee, if you tell them what you want done before you order them. Or, if you're going to try to get them for bottom dollar off of eBay or something, be prepared to spend money after they're delivered at the machine shop.

 

You could also have your pistons dished out. I had to notch mine a bit. My CR is right at 9.5 (9.485 or something) I kept it low on purpose.

1. Mileage - Everything put in it's place I should be able to achieve 22-26mpg highway.
2. The ability to use 89 instead of 91
3. The ability to add on a Procharger later down the line. I believe the stock l98 is 9.5:1. Though I have all forged internals so it makes things a bit different.

The Lt4 hot cam I think has a bit more umph! than your talking about. My heads are putting out 208/282 at .500 lift! and I know that this engine will be at at least 425hp. Though you are correct there are many more aggressive cams out there, but you than have to start gearing for your cam.

Is this a street vehicle or track only? If you will only live above 3000rpms than it may be a different story. I am looking at 2000 - 5000 with something that has street manners, hence the LT4 hot cam.

When it comes to AFR they will not want to mill their heads that much. They normally don't recommend it at all. They told me to deck my block, and notch my pistons, before milling the heads. Also as a side note, to my knowledge, the only heads AFR has ever offered in 58cc was there 180's when they were making them for the 305. They are no longer making those.

 

hrm... maybe ill look into a different block... That sounds like a little more than i am looking for. I really dont have the option of getting all this done at my leisure. Im off at school and saving for things that can be done this summer. I dont really have 6 weeks to wait for work being done to m car this summer. Heh, guess im just gunna have to look at this one weekend at a time. Thanks guys

 

I you want a deal on AFR Heads check out Dave at http://www.jdsperformance.com./index...tem&inmake=all He will order them from AFR and have them drop ship from AFR to you. The BEST price in the USA.

 

i'd go with a different block with flattop pistons so you could use those 68cc afr heads and have a reasonable compression ratio. their cnc ported comp packages are kinda pricey but tough to beat and don't even require a humongous cam to get big power. plus there are lots of naturally aspirated 350 fbodies out there running low to mid 11's with those heads.

 

could someone recomend a block that i can take a look at?

 

A flat-top 383 with the 68cc heads, zero-decked block, with typical 4-6cc valve reliefs in the pistons, would give you about 10.6:1 compression; which is right where you'd want to be.

Go find yourself a 350 block of whatever type you want (1- or 2-piece rea main seal, roller or not, etc.) and take it to your local racing machine shop that builds motors for the dircle-track guys that win; have them prep the block (bore .030", 9.000" deck or whatever the pistons require, etc.); buy some one of the good 383 kits (not just the cheapest one you can find from the cheapest source) and build yourself the perfect short block. If you don't trust yourself to build it, then pay them to assemble it for you. Either way, you'll come out cheaper than buying a ZZ4 abd modifying it, and you'll end up with a better result at the same time.

Don't expect the exact right thing to just fall out of heaven; do it yourself. That's what hot-rodding is all about .... doing it yourself, and getting the most for your money.

 

I'm building off my ZZ4 shortblock, ordered the AFR 195 L98 plug heads, these were the 74cc and they are milling them down to 58cc for me. So, yes they will do it. I'm also putting in a XR276-HR cam to match it and aslo an RPM Air Gap manifold with a 750DP, I'll let you know how it works out.

I researched a lot to put this motor together. Some might say I'm usuing too small of a cam but it actually gave me better results than some bigger cams as far as power across the entire RPM range on DD2000, plus it's more streetable which I need it to be. Combo says it shoudl be about 450/450, but I'm gonna dyno it onec it's done to see what it really is.