bigdom12

I have searched this forum in and out and have not found a single answer to my question. My motor has a blow headgasket, it is a 1988 Iroc with a 5.7 tpi. Rather than just puting the stock heads back on i want to upgrade to something better. I am looking to spend a max of 700$. I was thinking of the ZZ4 alumiunm heads but i have heard many bad things about them. The motor is all stock except for a few bolt ons. I plan on putting an LT4 hotcam in the near future. I was also looking at the edelbrock 60859, http://www.jegs.com/i/Edelbrock/350/60859/10002/-1 . But i am extremely unsure of what i should buy. I am open to any suggestoins that fall within my price range, which is a maxium of 700$.
Thanks,
Dom

Atilla the Fun

First, that $670 only gets you ONE Edelbrock head, not a pair. You need 2 heads, not just 1.
Second, there's nothing wrong with ZZ4 heads, they just don't flow any better than the heads you already have. This can be remedied with good porting.
If HP is more important to you than saving weight, then a good used pair of Vortec heads would be better, but most of your budget will have to go for a new, matching lower intake manifold.

MassD

iTrader: (1)

How much would porting cost, on avg at a machine shop?

MassD

iTrader: (1)

And i forgot to mention which one is more cost effictive porting the ZZ4 heads or the vortec heads?

bigdom12

Like MassD said how much will it cost to make the ZZ4 heads equivalent to a vortec head. Is it worth it to switch to the vortec heads, which would mean buying a new intake, or to just port the ZZ4 heads? Also if the vortec is the way to go what heads do you suggest. I was looking at these http://www.jegs.com/i/Patriot+Perfor.../2151/10002/-1 . And the weiand stealth ram intake, for the vortec heads. What do you think.

Atilla the Fun

49 porters out of 50 aren't good enough to get the ZZ4 heads to equal the stock GM Vortec heads, but a few of us can. I didn't say it was cheap, just that it is possible. Even so, my best ZZ4 heads don't surpass the flow of these: http://www.competitionproducts.com/R...info/RHS12410/
And if you're gonna buy aftermarket Vortec heads, it's these or nothing.
If you buy these heads, you'll also need these: http://www.competitionproducts.com/S...ductinfo/8440/
And as for the intake, even with the heads you already have, just switching from TPI to the HSR is worth 50 horses, because the TPI was designed for low rpm torque. The HSR does suffer below 3500 rpm, where 99% of your driving is done. The HSR is good for peak HP, but the average HP of TPI can still beat it if set up properly. Check out post 5 of this thread: https://www.thirdgen.org/forums/engi...st-builds.html

tkcaraudio

If your going to buy aftermarket heads just save up and buy a good pair.

Id find you a a good set of old school cast heads with 64/65 cc runners and a set of 202 valves and you will be happy with your performance. While its apart throw in some screw in studs and double or tripple valve springs and roller rockers....

Hell you can find you a set of good cast iron gm heads with 174/194 valves for $150 and then have a machine shop put 202s in it ect with the above for less then $700

I got a set of old school 327 LG heads thats fresh and 174 valves(stock rebuild) for $150 + Shipping The local machine shop I use said it be like 200 for the valve job. Screw In Studs/Guide Plates are about 100 and then roller rockers

bigdom12

Wow sounds like a great build, to bad it is just out of my price range. With these heads and intake, as well as a Cam, will the stock bottom end hold out, as well as the stock drive train? I have another option. The Vortec Heads off a 2000's truck or any 5.7 vortec motor. Will these work, becuase i could probabaly find a set cheap. And possibly get those ported. A

bigdom12

What do you consider a good affordable pair?

Atilla the Fun

The '96-'98 Vortec 350 heads are what I had in mind, but you went looking for the crappy Patriot heads.
The stock bottom end of the engine, as well as the stock drivetrain, is perfectly adequate for 350 horses and 400 ft-lbs torque, if you're not abusive.
If you do get the '96-'98 heads, here's the correct way to port them: https://www.thirdgen.org/forums/engi...c-heads-3.html

bigdom12

I dont think i am abusive, but i am a spirited driver. I dont beat the crap out of my car everytime i drive it but every once in the while i like to get on it. And i didnt know about the heads that is why i looked for them rofl.

Atilla the Fun

What a load of bad advice. Do all that you still won't equal stock Vortecs with just polishing the stock Vortec exhaust ports. The flow won't match, and the Vortecs also offer far more efficient combustion. That alone is a solid 10 horses in ANY combo.

tkcaraudio

My dads a machinest and I believe in old school heads lol

He has had a 8 second car since 93 thats street drivin on nitrous and boost and never had a problem from his cast heads

Let me check some casting numbers and let you know

Are you going Carbd or FI still?

bigdom12

Also i dont really want to assemble the heads. Are these the heads that you were talking about with the proper valves you told me, http://www.competitionproducts.com/R...fo/RHS12410K1/ . And do these come with valve springs aswell?

bigdom12

Thanks a lot. I was planning on keeping the FI

tkcaraudio

Is your car TPI for TBI?

I would still go with old school heads and use a 86 TPI set up or TBI set up for perimiter bolt heads

bigdom12

It is tpi and this is the setup that i think im ganna go with.
Vortec Heads http://www.competitionproducts.com/R...fo/RHS12410K1/
With a weiand stealth ram intake. Do you know if i will need to replace push rods as well or will the stock length orignals work? The only reason i am not going old school is becuase i want to keep the car sort of modern because it is a newer car.

Atilla the Fun

The assembled heads do include springs that, despite the claim, are good to 0.480" lift. Using these RHS Vortecs won't affect the pushrod length.

bigdom12

Ok now for a few more questions lol, sorry for picking your brain so much. What mm throttle body should i use 52mm or 58mm? What cam/rocker combo would you suggest for my application. I am looking for a mild motor, and i dont want to change my stock drive train around. I also want a lumpy idle. I am in love with the sounds lol. And thanks for ur help. Finally are these the same heads you were telling me about because they are far cheaper direct from RHS http://www.compperformancegroupstore...de=PT170cc64cc.

Atilla the Fun

If the 52mm TB isn't in your budget, just get a TPiS airfoil for your stock TB. Keep in mind that GM is using a stock 48mm TB on the 500 horse 502 Ram Jet crate engine.
If you do get a 58 mm TB, it'll feel great in the summer, because it'll sharpen your throttle response, though it may affect the tuning. But in the wet or snow, you'll be safest with a stock 48 mm TB.
Lumpy idle and EFI don't go together. If you want a lumpy idle, go carbureted, or go LSx. The LSx computers are so advanced that they can be tuned for the stupid-big cams that give a lumpy idle. But any cam that does give a lumpy idle is gonna be hell to drive below about 3000 rpm.
Choose a cam that has exactly no overlap at 0.050", nothing bigger or smaller, then adjust your exhaust sound with your choice of muffler.
With those heads, I very strongly suggest the GMPP "HOT" cam. It'll give you some exhaust sound, it'll pull best from 2500-6000 rpm, and it'll be tune-able with EFI. With 1.5:1 rockers, the lift is 0.492". That'd be a great start for you.
This combo will give 400 HP at 5500 rpm, at the crankshaft, assuming an adequate exhaust / headers. If you're using a 700R-4, hold first gear to 6200 for best acceleration.

bigdom12

Wow you are a plethora of knowledge, truly an asset to this forum. Thanks for all your help. I already have the airfoil installed so i think i am ok with that. Which Hot cam, lt4,? Also which lifters and push rods will i need with the new cam, links to websites or part numbers would just be godly, thanks.

Atilla the Fun

For lifters, used stock roller lifters are okay, but if you want to buy a new set, the best deal going is to order 12499225 from www.gmpartsdirect.com. These are for the LS9, but work perfectly for what you're doing. The cam is 24502586.
Used stock pushrods would also work if they're in good condition, and there are plenty of aftermarket upgrades in the same length.
Some Stealth Ram intakes have needed mild porting when fitting 58 mm TBs, pay attention if you do go that route.

bigdom12

i think i am going to stick to the 52mm when i do decide to upgrade. I cant thank you enough for your help, my final question is are these heads http://www.compperformancegroupstore...de=PT170cc64cc the same as these heads http://www.competitionproducts.com/R...fo/RHS12410K1/ because i think they are but i need a professional opinion.

Atilla the Fun

The biggest difference is the springs. I believe, but I'm not 100% sure, that the CP assemblies are with 1.25" springs, while the COMP assemblies are with 1.55" springs. You only need 100 pounds of spring pressure on the seats, and less than 320 pounds open, so that means you don't need 1.55" springs.
If you want, I'll double check. It's really no trouble.

Atilla the Fun

Why should anyone listen to you? Your dad, maybe, except that he doesn't have any experience flowing or dynoing heads, or else you would've bragged about it. Wanting to help is one thing, but giving outdated advice is something far, far worse. Every kid thinks his dad is a god, but it ain't so.

MassD

iTrader: (1)

This is one of the most helpful topics. thank you guys so much

bigdom12

I would really appreciate it if you would. Which head would be better for me to buy. The CP one or the one direct from RHS.

Atilla the Fun

buying direct is nearly $1100/pr. but buying from CP still gets the excessively stiff springs. Buy a bare pair from CP, and the valves I suggested, then have a local machine shop assemble them with these springs: http://www.competitionproducts.com/H...uctinfo/98214/
Stock retainers will do fine, have the shop set the installed height to 1.71", and then use 1.5:1 rockers.
If you later want to try 1.6:1 rockers, you'll need to buy much more costly springs.
Another advantage of going this route is you can have the shop put a small 30-degree back cut on each and every valve.
You still come out money ahead this way, and get slightly better performance.

bigdom12

How much would it cost to do all of that? If i added everything up right it would come out to 650 bucks which is 90 bucks less than the assembled ones. I dont think a machine shop would only charge me 90 bucks to assemble and cut the heads. Unless i have no idea on the prices. And which springs would i get for the 1.6:1 rockers just so i can see if i can squeeze it into my budget.

Atilla the Fun

they don't need to cut the heads, Assembly takes about a half hour at most, so no more than $50 for that. Back-cutting the valves should be under $2 per valve, so you're still ahead.
Using the COMP springs will collapse the lifters, hurting upper-rpm performance.
You can probably get CP to assemble the bare heads with the valves and springs I suggested, that way they'd arrive ready to bolt on.

bigdom12

I think that is what i will do thanks so much

tkcaraudio

I agree with above statements RHS is a good head...

you can buy Vortecs from jegs for around $800 a set complete if you look

bigdom12

I called up CP and they said they assemble the heads but they do not back cut them. The guy also suggested that i run the 98212 springs because of the lift of the cam. He said that the 98214 do not have enough pressure because they are for a stock hyd. roller. He also said it would be cheaper for me to buy the heads assembled and just change the springs out. What do you think.

bigdom12

The RHS heads from competition products are only 740 assembled and if i get these springs they will only cost 40 bucks. And maybe i can change them myself.

Atilla the Fun

I didn't think they'd do the back-cutting. If you order the complete RHS assemblies, you're not just changing springs, you're also changine retainers. Your old heads have half the retainers you'd need, but the old 350 exhaust retainers are rotators, so they're not gonna work for this.
The 98212 springs are much stiffer than I'd ever use with the HOT cam and LS9 lifters, let alone used stock lifters. They'll hurt performance above 5000 rpm.
So, buy the heads bare, add the valves and the 214 springs, then visit a local machine shop for assembly. It's slightly cheaper, and it gives slightly better results.

bigdom12

I dont plan on doing the hot cam and lifters now. I am just going to change the heads and the intake. Will the 98212 springs work with a stock cam until i am ready to install the cam?

Atilla the Fun

yes, they'll be fine, no problem.

bigdom12

Sweet. Also will the stock injectors work with the weiand stealth ram intake?

Atilla the Fun

I don't know.