Going to start working on my C4 soon

[vetteboy86]

What are the specs on the ZZ4 cam? So you are doing a complete rebuild, or just the top end, I am confused????

 

[Edmond]

What are the specs on the ZZ4 cam? So you are doing a complete rebuild, or just the top end, I am confused????

Nope, I'm not doing a complete rebuild. At least not as of yet. But if I encounter serious problems when the motor is pulled, I would rebuild it. As of now, I'm planning on heads, cam, ported intake and headers. That's just the performance stuff. The regular wear and tear stuff, I'll probably replace because it'll be easier to do it now than to have the water pump fail a few thousand miles later, or the oil pump, or the fuel pump.

I'm going to do poly bushing all the way around, now ball joints, shocks, etc... But that won't be until early next year.

 

[Larry's Yellow Rdstr]

Edmund,

Its exciting to build an engine, especially when you first start it up after the rebuild. I recently did a 383 for my sons' El Camino. I'm making plans for my 87 over the winter..so I'm following your situation closely. Detail the engine bay while the old engine is out.
Best of luck and keep the wave.
Doc

 

[74bigblock]

Dave, I'll keep you posted. Guy I bought the heads from lives out near the Lockport area. His Mini Ram ZZ4 really pulls hard! You can really hear the cam on that thing. :L

You still haven't gone for a ride in the '74 :W !!!! Do you plan on going to that show on Oct 1 in Oak Brook?

 

[Edmond]

You still haven't gone for a ride in the '74 :W !!!! Do you plan on going to that show on Oct 1 in Oak Brook?

Unfortunately, I won't be able to do anything that weekend. I have the whole weekend committed to an advanced handgun class I'm taking through the Lethal Force Institute. 1500 rounds in 2 days? We'll be shooting until we puke.

 

[Larry's Yellow Rdstr]

What handgun is your favorite. I've had a little experience in the past.

 

[max]

Sorry , for the dumb question , Edmond , but whats the advantages of a ZZ4 heads ?
better flow ?
Why I'm askin' is is it possible to port usual heads to that specs of a ZZ4?

 

[89ZZ4]

Sorry , for the dumb question , Edmond , but whats the advantages of a ZZ4 heads ?
better flow ?
Why I'm askin' is is it possible to port usual heads to that specs of a ZZ4?

There's no difference between the 88-91 head castings. The difference in the ZZ4 head is that it has slightly better valve seat and valve angle cuts probably due to improved production methods over the years which would probably help low lift flow some. The main advantage is that they come with the LT4 springs which are also known as the Hot Cam springs so it can handle a larger than stock cam to .525 gross lift at the valve and with the stronger spring and lighter weight retainers you will get better valve train control. In Edmonds case thay came with ARP studs and have been lightly cleaned up so they ended up being cheaper than a valve job with new springs and studs plus they are plug and play for him. These heads can support to 390-400 FWHP which is more than Edmond is shooting for.

 

[Edmond]

What handgun is your favorite. I've had a little experience in the past.

Sig Sauer P229 in .40 S&W or Glock 30 in .45 ACP. I shoot moving targets easier than stationary targets for some reason.:confused

 

[Edmond]

In Edmonds case thay came with ARP studs and have been lightly cleaned up so they ended up being cheaper than a valve job with new springs and studs plus they are plug and play for him. These heads can support to 390-400 FWHP which is more than Edmond is shooting for.

With only 5000 miles on the heads, that is barely broken in. I'm only shooting for 325-350 FWHP. I'm not a drag strip type of guy, it's a car mainly used around town. I rarely drive on the expressway because I'd be too tempted to speed.:L

 

[vetteboy86]

I think you will be surprised with the outcome. That is only what an 80 hp increase. I would imagine you will see at least 350 at the flywheel. I think a year or two done the road, I am going to buy a set of heads, and bolt them on. Just didn't have the money right now. Heck I still dont have the long tubes.

 

[Larry's Yellow Rdstr]

Carried the Glock 30 for several years on my dept. They don't get much better!

 

[Mad-Mic]

Edmond,

do yourself a favor and get a better spring. a spring that is *rated* upto .525 lift isn't enough for a .525 lift cam. get springs that are good to .600 lift. that way if you go with 1.6 RR's it will move the lift upto .555". what happens to a spring that is close the the lift of the cam is it will get soft over time and the lifters won't follow the cam lobe and will get sloppy.

just a piece of mind like those hardened pushrods. also get a fresh set of roller lifters. they are cheap. should only cost you 200 for both at most. (springs and lifters)

80 bucks for roller lifters
80 bucks for hardened pushrods
100 bucks for springs.

if your gonna do it, do it right! trust me you don't want a spring to wear out and even break or all your hard work will go down the drain and will cost you another 3k easy. in this case it's better to have too much spring than not enough. worst case with too much is premature cam wear. lobe gets worn down. worst case with soft springs is you drop a valve on the piston and it will be like hammer to anvil. :bang

 

[89ZZ4]

Mad-Mic

I agree that Edmond should consider some new lifters and push rods but the heads I sold him have less than 5K on them are in great shape. The springs are fine for his application and are the LT4/Hot Cam springs which run "at" .525 gross lift with the hot cam and 1.6 roller rockers. I ran these heads with my ZZ-409 cam at a .520 gross lift. They have been lightly cleaned up and 1204 gasket matched and have the ARP pro series studs. I told him to have them checked out and if they weren't in top shape I'd give him his money back. I was also going to give him the ZZ4 cam but it's taken a hike. I have also recommended that he use the GM Performance self-aligning roller rockers (crane gold race) in either the 1.5 or 1.6 ratio depending upon his cam choice. Considering where Edmond is going at max, this set up will safely work well for him.

Phil

 

[Edmond]

Mic,

Where did you see roller lifters for $80? The lowest priced roller lifters I could find were $220.

I'm not trying to do anything radical. I just want something that will get me 300 HP and almost 400 ft. lbs. It'll be a daily driver, won't even see much expressway time. I still want good gas mileage as well.

I'm not going to build something like Phil's monster! :L

 

[Mad-Mic]

Mic,

Where did you see roller lifters for $80? The lowest priced roller lifters I could find were $220.

I'm not trying to do anything radical. I just want something that will get me 300 HP and almost 400 ft. lbs. It'll be a daily driver, won't even see much expressway time. I still want good gas mileage as well.

I'm not going to build something like Phil's monster! :L

i could of swore i seen them when i was marking off parts for my build. Rich gave me a catalog that he used and i need to find it and recheck.

i did find these straight out of jegs....
270-10530-16Hydraulic Roller Lifters
SB-Chevy 305ci/350ci/LS-1 5.7L 1987-98
<LI>Complete Set, 16/pkg
| More Details $189.99

http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=1225&prmenbr=361

 

[Mad-Mic]

Mad-Mic

I agree that Edmond should consider some new lifters and push rods but the heads I sold him have less than 5K on them are in great shape. The springs are fine for his application and are the LT4/Hot Cam springs which run "at" .525 gross lift with the hot cam and 1.6 roller rockers. I ran these heads with my ZZ-409 cam at a .520 gross lift. They have been lightly cleaned up and 1204 gasket matched and have the ARP pro series studs. I told him to have them checked out and if they weren't in top shape I'd give him his money back. I was also going to give him the ZZ4 cam but it's taken a hike. I have also recommended that he use the GM Performance self-aligning roller rockers (crane gold race) in either the 1.5 or 1.6 ratio depending upon his cam choice. Considering where Edmond is going at max, this set up will safely work well for him.

Phil

Phil,

I believe your heads are in "Great" shape. no worries there what Edmond said was that the max spring lift is .525 and then he said he wants to run a cam upto that lift rate. well that will not work. it might work for alittle while but springs lose their retention over time and "Soften" up substantially.

The most common mistake I see in engine building is to use valve springs with inadequate pressure. Not all springs are created equal; just because a set of coils is described as "roller springs" in a catalog or advertisement does not mean that the springs will produce enough pressure to do their job.

Several misconceptions about valve springs influence racers to make poor decisions. A customer who says, "I don't need good springs because I'm running stock valves," is badly mistaken. Steel valves are heavy, and adequate spring pressure is absolutely essential to control their motion. A valve's inertia increases with the square of the engine speed, so even a small increase in rpm requires significantly more spring pressure to maintain valvetrain stability.

It is a myth that stiff springs will pop the heads off valves or cause valve tuliping. The only time that the valve head is subject to spring tension is when the valve is closed and resting on its seat. At all other times, the valve sees only a compressive load between the tip of the valve stem and the groove for the valve locks. In our Pro Stock engines, we use 7-inch-long titanium valves with tiny 7 millimeter stems and springs that exert more than 1,000 pounds of open pressure — and we've never broken or tuliped a valve due to high spring pressure.

In fact, too little spring pressure is almost always the root cause of valvetrain failures. We spent a year studying valve springs using an Optron, a sophisticated electronic device that can precisely record valve motion and reveal valve float. We learned some shocking truths about valvetrain behavior at high rpm. Even with a relatively mild camshaft profile, the valves bounce on their seats before they close. If the spring is too light, the valve bounces uncontrollably. The valve hits the seat, rebounds, hangs in the chamber a while, then bounces erratically several more times. Imagine how hard this is on the valve and the rest of the valvetrain!

Even with high-pressure springs, the valves still bounce when they close. The crucial difference is that the bounce is controlled and predictable, like dropping a basketball. The valve bounce diminishes progressively, and generally, on the third bounce, the valve stays closed until the next cycle.

The evidence is unmistakable when we tear down an engine that has been run with weak springs: The valve seats are usually beaten up, the valve job is wiped out, and there is fretting on the valve faces. It's fortunate when we catch these problems early because weak springs will almost certainly cause a catastrophic failure.

Another excuse I've heard for not using stiff valve springs is that they take more horsepower to compress. My reply is that each spring stores energy, and for every valve that is opening, another one is closing. Anyone who has been whacked by a torque wrench while turning a crankshaft can testify that the valve springs exert considerable force on the closing ramps!

I have never installed stiffer valve springs on an engine and lost power; the improvement in valvetrain dynamics more than offsets whatever additional power is required to overcome the springs' resistance.

http://www.nhra.com/dragster/1999/issue02/Tech_Speaking.html

this is why i stated to go with a stiffer spring. a .600" lift spring will be enough for what ever he does. if your gonna do it, do it right thats all i'm saying.

BTW were you running the ZZ409 cam on a 350 shortblock or stroker? if so how did you like it? i've been sitting on a ZZ409 cam for over 2 years piecing my parts together. any dyno sheets?