DragonFire~

I put a stock ZZ4 crate motor in my 75 Stingray with the stock TH400 transmission and stock rear-end/gears. I want to upgrade the heads and cam. What are the opinions on GM's Fastburn heads and the GM LT4 Hydraulic roller tappet Hot cam?

I think my goal right now is around 500HP at the crank

I have been told that I can get around 430HP with the fastburn heads and the LT4 Hotcam. Beyond that a good carburetor could boost it to maybe 450HP. I have been pricing stuff and I think I can get all this for $1,500 or so.

Beyond that I'm not sure what performance stuff I can do, new intake manifold? The only issue with that is I have the factory low hood and I don't want to replace it. I already have a Holly 750CFM street carb with the KN drop top air cleaner.

So are the fastburn heads and the Hot Cam the best upgrade for the ZZ4 or are there much better ways to go? The fastburn heads are aluminum like the stock heads I have on the ZZ4 I would like to stay with aluminum.


Fastburn heads:
http://store.summitracing.com/partde...5&autoview=sku

LT4 Hot cam:
http://store.summitracing.com/partde...5&autoview=sku

Carl Johansson

you will make about 450 with the heads and the hotcam - but you will need a different carb. that about maxes out the engine - your looking at a whole lot of changes top get to 500 hp - and big bucks. If you want 500 - and your set un it - you need to come up with a plan - so you don't keep buying parts - trying em and finding out they don't play well with the other parts you are throwing at the engine!

Carl Johansson

Kalway

After 400hp, you're getting in to race fuel territory, for a 350. The solution to that is more cubes! No replacement for displacement. You want power without having to break the bank, that's how you do it.

alnukem

Why don't you get Super Chevy's articles called "Danger Mouse"? They did a lot of dyno testing including the Fast Burns & ended up trecommending the 170 cc E-Tec heads. They were knocking on 500 HP & said it was great for drivability. They also said this would work for any flat top piston small block like your ZZ4. It was something like

Edelbrock E-tec 170 cc heads #60979
Edelbrock Air Gap Manifold #7516
Edelbrock Hyd Roller #2201
& a Petronix Ignition

Do a Google search. Good Luck!

jcswm

I started out with a Crate Iron head ZZ4 350hp engine, added a GM Hotcam, 1.6 RR's GM performance Intake, Hooker Headers/Sidepipes with the glasspacks, MSD HEI Ignition and my choice of carbs, Started with a Q-jet, currently I'm running the Eldelbrock and I'll try the Holly now that it's cooled off enough outside to set it up right!!!
I Don't know how much hp I'm making but it's DAMN QUICK!!!

DragonFire~

Well it looks like I'll be getting the FastBurn Heads and the HotCam then. Is the 1.6 RR's GM performance Intake best for this combo? Also what carb should I go with? I like the Holly carbs so a 750CFM double pumper?

DZRick

With everything you've got listed there, you've basicly built the ZZ430 clone 430hp/430ftlbs.

GM suggests a 750 Holley and a fuel pump with more GPH.

DragonFire~

Now about the intake manifold, it looks like the GM Eliminator intake works with the fastburn heads. But it looks like it might be taller than the stock ZZ4 aluminum intake?

Also with this combo can I run pump gas?

Eliminator intake:
http://store.summitracing.com/partde...5&autoview=sku

alnukem

You really ought to pay attention to the "Danger Mouse" article, I looked it up, Max 480 HP / 458 footpounds & here's the real killer, Average from 2600 RPM to 6000 RPM 356 HP/ 430 footpounds. Why duplicate a 435 horse motor when you can get a 480 horse with excellent street manners at the same price. Just trying to help.

Fevre

Fast burn are nice heads but you can do better for the same $; Edlebrock, Trick Flow and AFR come to mind\

Have a 350, HOT cam with 1.5 rockers along with Trick Flow twisted Wedge heads in my Formula, torq monster out of the whole with a 700r4 and 3.73 gear.

jackson

ZZ4 is assembled & ships with dished pistons. It gets its ~10:1 CR from small 58cc chambers.

alnukem

I always wondered why they had such small chambers.....Thanks!