zz4 power upgrade
Thread Starter
Race Director
Joined: Apr 2003
Posts: 13,300
Likes: 16
From: TX
St. Jude Donor '12-'13
zz4 power upgrade
I am thinking the following upgrade to my ZZ4 in my 80:
http://popularhotrodding.automotive....ld/index1.html
I don't really want to change the heads so I think I would stop after stage 3.
Question 1: PHR used an Edelbrock Air Gap intake which does not fit under a stock C3 hood, from what I read. I really don't want to have to buy a new hood and have it painted. Is there is similar intake that would fit under the stock hood? Or would the ZZ4 intake work about as well?
Question 2: Has anyone done this upgrade or a similar one, and if so, did you achieve similar results?
http://popularhotrodding.automotive....ld/index1.html
I don't really want to change the heads so I think I would stop after stage 3.
Question 1: PHR used an Edelbrock Air Gap intake which does not fit under a stock C3 hood, from what I read. I really don't want to have to buy a new hood and have it painted. Is there is similar intake that would fit under the stock hood? Or would the ZZ4 intake work about as well?
Question 2: Has anyone done this upgrade or a similar one, and if so, did you achieve similar results?
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
recognise baseline was 344
hi-ratio rockers made 16 more
bigcam2 w/ springs&retainers & intake made 48 more (total 408)
all that for about 60-65 more hp? about 18% increase. poor roi
me thinks stock rockers, stock intake, ported zz4 heads & good cam & good springs will make +400.
L98/ZZ4 heads are good up to a point .... but they have relatively small intake port volume coupled with not so advanced comb chamber design. They can be ported but that's more dough. If you're looking to make much more than 400 hp ... suggest first swap to heads w/ good springs & bigger cam first.
stock zz4 intake man will flow about all zz4 heads can be coaxed to flow. Intake ain't your bottleneck.
keep in mind, zz4 heads have Small 58cc comb chambers that make lotsa compression. Some but Few aftermarket heads are less than 64cc ... be prepared to lose a good half-point of comp.
& keep all this in perspective ... PHR is hawking parts for their advertizers ... & you (nor they) sure don't need $118 pushrods for this .
hi-ratio rockers made 16 more
bigcam2 w/ springs&retainers & intake made 48 more (total 408)
all that for about 60-65 more hp? about 18% increase. poor roi
me thinks stock rockers, stock intake, ported zz4 heads & good cam & good springs will make +400.
L98/ZZ4 heads are good up to a point .... but they have relatively small intake port volume coupled with not so advanced comb chamber design. They can be ported but that's more dough. If you're looking to make much more than 400 hp ... suggest first swap to heads w/ good springs & bigger cam first.
stock zz4 intake man will flow about all zz4 heads can be coaxed to flow. Intake ain't your bottleneck.
keep in mind, zz4 heads have Small 58cc comb chambers that make lotsa compression. Some but Few aftermarket heads are less than 64cc ... be prepared to lose a good half-point of comp.
& keep all this in perspective ... PHR is hawking parts for their advertizers ... & you (nor they) sure don't need $118 pushrods for this .
Thread Starter
Race Director
Joined: Apr 2003
Posts: 13,300
Likes: 16
From: TX
St. Jude Donor '12-'13
recognise baseline was 344
hi-ratio rockers made 16 more
bigcam2 w/ springs&retainers & intake made 48 more (total 408)
all that for about 60-65 more hp? about 18% increase. poor roi
me thinks stock rockers, stock intake, ported zz4 heads & good cam & good springs will make +400.
L98/ZZ4 heads are good up to a point .... but they have relatively small intake port volume coupled with not so advanced comb chamber design. They can be ported but that's more dough. If you're looking to make much more than 400 hp ... suggest first swap to heads w/ good springs & bigger cam first.
stock zz4 intake man will flow about all zz4 heads can be coaxed to flow. Intake ain't your bottleneck.
keep in mind, zz4 heads have Small 58cc comb chambers that make lotsa compression. Some but Few aftermarket heads are less than 64cc ... be prepared to lose a good half-point of comp.
& keep all this in perspective ... PHR is hawking parts for their advertizers ... & you (nor they) sure don't need $118 pushrods for this .
hi-ratio rockers made 16 more
bigcam2 w/ springs&retainers & intake made 48 more (total 408)
all that for about 60-65 more hp? about 18% increase. poor roi
me thinks stock rockers, stock intake, ported zz4 heads & good cam & good springs will make +400.
L98/ZZ4 heads are good up to a point .... but they have relatively small intake port volume coupled with not so advanced comb chamber design. They can be ported but that's more dough. If you're looking to make much more than 400 hp ... suggest first swap to heads w/ good springs & bigger cam first.
stock zz4 intake man will flow about all zz4 heads can be coaxed to flow. Intake ain't your bottleneck.
keep in mind, zz4 heads have Small 58cc comb chambers that make lotsa compression. Some but Few aftermarket heads are less than 64cc ... be prepared to lose a good half-point of comp.
& keep all this in perspective ... PHR is hawking parts for their advertizers ... & you (nor they) sure don't need $118 pushrods for this .
Any one else have any input?
Thread Starter
Race Director
Joined: Apr 2003
Posts: 13,300
Likes: 16
From: TX
St. Jude Donor '12-'13
& keep all this in perspective ... PHR is hawking parts for their advertizers ... & you (nor they) sure don't need $118 pushrods for this .
Interesting. Do others concur? Do you think their HP numbers are suspect as well?
Interesting. Do others concur? Do you think their HP numbers are suspect as well?
Pro
Joined: Jun 2005
Posts: 725
Likes: 1
From: FL.
I agree with Jackson.
That isn't a real good Bang for the Buck write up, especially the head swap part
You can get those beehive springs and change them yourself on your 58cc aluminum heads, then go up 2 notches with a comp HR cam.
I think you will have enough play with a new head gasket thickness to get a 10:1 CR.
The Airgap manifold may be worth a little gain?
For under 1K$ you should be at 375HP. With some porting on the zz4 heads, maybe 400+.
An air gap should fit under your hood with a dropbase canister, the airgap RPM would be a little to Tall.
That isn't a real good Bang for the Buck write up, especially the head swap part
You can get those beehive springs and change them yourself on your 58cc aluminum heads, then go up 2 notches with a comp HR cam.
I think you will have enough play with a new head gasket thickness to get a 10:1 CR.
The Airgap manifold may be worth a little gain?
For under 1K$ you should be at 375HP. With some porting on the zz4 heads, maybe 400+.
An air gap should fit under your hood with a dropbase canister, the airgap RPM would be a little to Tall.
Last edited by 69vettester; Jun 24, 2010 at 07:23 PM.
Thread Starter
Race Director
Joined: Apr 2003
Posts: 13,300
Likes: 16
From: TX
St. Jude Donor '12-'13
I agree with Jackson.
That isn't a real good Bang for the Buck write up, especially the head swap part
You can get those beehive springs and change them yourself on your 58cc aluminum heads, then go up 2 notches with a comp HR cam.
I think you will have enough play with a new head gasket thickness to get a 10:1 CR.
The Airgap manifold may be worth a little gain?
For under 1K$ you should be at 375HP. With some porting on the zz4 heads, definitely 400+.
An air gap should fit under your hood with a dropbase canister, the airgap RPM would be a little to Tall.
That isn't a real good Bang for the Buck write up, especially the head swap part
You can get those beehive springs and change them yourself on your 58cc aluminum heads, then go up 2 notches with a comp HR cam.
I think you will have enough play with a new head gasket thickness to get a 10:1 CR.
The Airgap manifold may be worth a little gain?
For under 1K$ you should be at 375HP. With some porting on the zz4 heads, definitely 400+.
An air gap should fit under your hood with a dropbase canister, the airgap RPM would be a little to Tall.
I think if I just get the beehive springs, comp HR cam, and have the ZZ4 heads ported, I would end up spending over $1000, right?
I guess I'm just trying to find the most economical route to over 400 hp.
I hear there is still a market for ZZ4 heads, so I *may* consider selling mine and going with some better flowing ones.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
Pro
Joined: Jun 2005
Posts: 725
Likes: 1
From: FL.
[QUOTE=KWIL;1574495834]Pace has a kit claiming 408 HP for under a grand. http://paceperformance.com/index.asp...&ProdID=229106 (The HP claimed is achieved w/ a differant intake, however.)
I think if I just get the beehive springs, comp HR cam, and have the ZZ4 heads ported, I would end up spending over $1000, right?
QUOTE]
A worthy porting of your heads would put the total cost to around $1200-1400 thats a good deal, to get your allready HiPer engine to possibly 400HP?
Keep in mind, 400hp is alot harder to get with a 350 than a 383 thats for certain.
I would feel Ive reached the tops with a reliable zz4 street machine by getting 375HP. with the cam upgrade, springs, and a real nice Port Job. Youd be going radical to expect 400+. ZZ383 is in that world
Also...
Im not so sure about putting 195cc or 200cc heads on your 350ci. May defeat your potential? Maybe someone who knows more about what it takes for a 350ci to run with 200cc intake runners will chime in?
I think if I just get the beehive springs, comp HR cam, and have the ZZ4 heads ported, I would end up spending over $1000, right?
QUOTE]
A worthy porting of your heads would put the total cost to around $1200-1400 thats a good deal, to get your allready HiPer engine to possibly 400HP?
Keep in mind, 400hp is alot harder to get with a 350 than a 383 thats for certain.
I would feel Ive reached the tops with a reliable zz4 street machine by getting 375HP. with the cam upgrade, springs, and a real nice Port Job. Youd be going radical to expect 400+. ZZ383 is in that world
Also...
Im not so sure about putting 195cc or 200cc heads on your 350ci. May defeat your potential? Maybe someone who knows more about what it takes for a 350ci to run with 200cc intake runners will chime in?
Last edited by 69vettester; Jun 24, 2010 at 05:47 PM.
Thread Starter
Race Director
Joined: Apr 2003
Posts: 13,300
Likes: 16
From: TX
St. Jude Donor '12-'13
Looks like there are a few ways to skin a cat.
I'm hoping someone on CF has actually done some of these mods on a ZZ4 and can offer some insight/ advice.
Last edited by KWIL; Jun 24, 2010 at 11:54 PM.
Thread Starter
Race Director
Joined: Apr 2003
Posts: 13,300
Likes: 16
From: TX
St. Jude Donor '12-'13
Drifting
Joined: Mar 2007
Posts: 1,936
Likes: 1
From: Winston-Salem NC
I used to live not that far from El Paso - Alamogordo,NM. Used to go through Amarillo a couple of times a week driving a big truck after retiring from the military. I go through every now and then on a run to the West coast. I like Texas - great people.
Thread Starter
Race Director
Joined: Apr 2003
Posts: 13,300
Likes: 16
From: TX
St. Jude Donor '12-'13
Racer
Joined: Mar 2008
Posts: 315
Likes: 0
From: KY
It still sitting on the stand but its based on GMs zz430 just with smaller port AFr heads I had the chambers milled down to 62 cc on the AFR sight there are 2 engines that are simular they are makeing somewhere between 430 and 450 hp and both make 470 torque I hope I get somewhere close to this
Race Director
Joined: Jun 2000
Posts: 10,036
Likes: 667
From: FL
Avoid the Thumpr cams. All show and no go.
Get some good AFR heads and bigger hyd roller and enjoy.
If you want to go radical, here is 520 hp @6600 rpm build up of a ZZ4.
http://www.carcraft.com/techarticles...ine/index.html
Get some good AFR heads and bigger hyd roller and enjoy.
If you want to go radical, here is 520 hp @6600 rpm build up of a ZZ4.
http://www.carcraft.com/techarticles...ine/index.html
Last edited by SteveG75; Jun 25, 2010 at 12:08 PM.