ZZ4 Upgrade Suggestions?
Thread Starter
Racer
Joined: May 2002
Posts: 280
Likes: 0
From: Poughkeepsie New York
ZZ4 Upgrade Suggestions?
I have a ZZ4 in the 79, with 4 speed and 3.70 rearend. Is there anything I should consider changing to get more snap out of this? I will list what I have done, would appreciate any suggestions form the motorheads. I guess what I am looking is suggestions like a different intake etc...
My mods:
Deamon 650
Headers
March Pulleys
Accel Coil
K&N filters
True Dual with X pipe
Flowmaster 50 series
This is a stock ZZ4. Thanks in advance.
My mods:
Deamon 650
Headers
March Pulleys
Accel Coil
K&N filters
True Dual with X pipe
Flowmaster 50 series
This is a stock ZZ4. Thanks in advance.
Race Director
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
Re: ZZ4 Upgrade Suggestions? (L82-JWS)
might consider going with a GM HOT cam, there are a pretty good deal at about $200, you should be able to run it without needing any other parts but you will not get the full 218/218 dur and .525/.525 lift with 1.5 rockers, it is rated using 1.6 rockers. You will be at about 216 dur and .492 lift with 1.5 rockers. I am running the Hot cam in my Formula with 1.5 rockers and it is makes nice mid range power, should get you up around 390-400 hp.
Thread Starter
Racer
Joined: May 2002
Posts: 280
Likes: 0
From: Poughkeepsie New York
Re: ZZ4 Upgrade Suggestions? (Fevre)
You happen to know which PN that is? If you do that upgrade, would you recommend the 1.6 rockers? This is a street car, dont do the track...thanks.
Race Director
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
Re: ZZ4 Upgrade Suggestions? (L82-JWS)
It is part # 24502586, at www.gmpartsdirect.com it is only $175, way cheaper than most roller cams. If you already have 1.5 roller rockers I would not spend the $ for 1.6, they are $200+ for the self aligning kind you need and you will only pick up maybe 20 hp max. I am very pleased with the set in my formula for street use.
Race Director
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
Re: ZZ4 Upgrade Suggestions? (L82-JWS)
FYI just read the desc on the gmparts.com website and there is minor alteration needed for the dowel pin:
DESCRIPTION: LT4 HOT CAMSHAFT
This hydraulic roller cam is for service only for all V8 engines with roller camshafts. The duration at lash point in degrees (intake/exhaust) is 279/287; duration at .050" tappet lift (intake/exhaust) is 218/228; and maximum lift with 1.6 rocker ratio (intake/exhaust) is 525/525. Valve lash is zero/zero and lobe centerline is 112 degrees. Technical Notes: The LT4 camshaft P/N 24502586 was designed to be used in a number of different engines. Therefore, the following change may need to be made to allow for correct assembly of the engine: For LT1 and L98 engines 1995 and before, the dowel pin in the end of the camshaft must be pushed in so extension from end of cam is .30+/-.01", the same as the production part. For 1996 LT1 and LT4 engines, the dowel pin is in the correct position, extending .620" from the end of the camshaft. This camshaft has a fuel pump lobe
This hydraulic roller cam is for service only for all V8 engines with roller camshafts. The duration at lash point in degrees (intake/exhaust) is 279/287; duration at .050" tappet lift (intake/exhaust) is 218/228; and maximum lift with 1.6 rocker ratio (intake/exhaust) is 525/525. Valve lash is zero/zero and lobe centerline is 112 degrees. Technical Notes: The LT4 camshaft P/N 24502586 was designed to be used in a number of different engines. Therefore, the following change may need to be made to allow for correct assembly of the engine: For LT1 and L98 engines 1995 and before, the dowel pin in the end of the camshaft must be pushed in so extension from end of cam is .30+/-.01", the same as the production part. For 1996 LT1 and LT4 engines, the dowel pin is in the correct position, extending .620" from the end of the camshaft. This camshaft has a fuel pump lobe
Melting Slicks
Joined: Feb 2003
Posts: 3,053
Likes: 4
St. Jude Donor '03,'11
Re: ZZ4 Upgrade Suggestions? (L82-JWS)
i wonder how much it would cost to get those L98 heads cut for 2.02 and 1.6 valves.
I have a goodwrench crate with those heads with a flat tappet 208/212 cam but wonder if a bigger cam would be limited by the 1.94/1.5 valves?
I have a goodwrench crate with those heads with a flat tappet 208/212 cam but wonder if a bigger cam would be limited by the 1.94/1.5 valves?
Team Owner
Joined: Feb 1999
Posts: 34,453
Likes: 665
From: Republic of Texas
Re: ZZ4 Upgrade Suggestions? (turtlevette)
i wonder how much it would cost to get those L98 heads cut for 2.02 and 1.6 valves.
I have a goodwrench crate with those heads with a flat tappet 208/212 cam but wonder if a bigger cam would be limited by the 1.94/1.5 valves?
I have a goodwrench crate with those heads with a flat tappet 208/212 cam but wonder if a bigger cam would be limited by the 1.94/1.5 valves?
Melting Slicks
Joined: Feb 2003
Posts: 3,053
Likes: 4
St. Jude Donor '03,'11
Re: ZZ4 Upgrade Suggestions? (Corey_68)
The biggest valves that will fit the L98 heads are 2.00, 2.02 are too big.
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