A friend of mine is in a bind with the setup he is going with. His car is a '92 Z-28 and here's what's going into it:
bored .030 over rebuilt engine
AFR 190 heads
ZZ9 cam
Superram intake with TPIS base
58mm throttle body
1 3/4" SLP headers
3" american thunder exhaust
3.73 gears
custom chip
rebuilt tranny w/racing clutches
Vigilante 2800 stall converter

All these parts he has already except for the chip. Will this setup be enhanced or hurt by putting on 1.6 rockers instead of the 1.5's that the ZZ9 is shown with? Thanks in advance.

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Erik '89 Formula 350 TPI
13.96 @ 97 on motor
12.83 @ 109 w/NOS
http://www.geocities.com/formulal98/

 

Since its a pretty well tricked out car, I don't see any harm in going with the 1.6 roller rockers. The car will benefit from the more lift you will get you get with the 1.6s.

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1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission with 2.77:1 Rear End

Current Mods: LT4 Hot Cam, Edelbrock TES 1 5/8" Headers, Hooker 3" Aerochamber Cat-Back System, Gutted Catalytic Converter, Performance Resource Chip, Accel Ignition Coil, Cap, Rotor, 8.8mm Wires, K&N Filters, JET TPI Air Foil, Fully Ported TPI Plenum and Base, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

 

1.6 on the intake will not affect the idle notable and you will gain some power, if you go for 1.6 on both intake and exhaust your idel will suffer but you will gain a few xtra hp.
Go for 1.6 on intake and 1.5 on exhaust, just my opinion.

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GTA -89:Free flow muffler,dual 3" HF cats, Edelbrock headers, Vette heads, 1.52 RR 7/16, ZZ-9 cam, Big Mouth, AS&M LTR, !plenum, 52 TB, MSD 6AL, TPIS level V prom, Superior shift-kit and all the minor mods. and more to come!
http://www.itv.se/tacs/members_cars/m279/m279.html (Swedish Trans Am Club)

 

Make sure the springs on those heads can handle the extra lift on the exhaust side. I think its about .540" lift with 1.6's.

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West Coast GM Shootout 2001!
1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-

 

I put up a response on another thread answering the question of how the ZZ9 idles with different ratio rockers.

In summary, going from 1.5s to 1.6s on the intakes while leaving 1.5s on the exhausts makes a noticable difference in power with little idle degradation. Adding 1.6s to th exhaust while keeping 1.6s on the intakes costs about 2 Hg of vacuum and in a 350/355 makes the idle more noticable, but far from objectionable.

In my 415 I've got 1.6s on both and you really can't tell there's a cam in the engine. The cubes cover the overlap and duration.

I've tired that cam in all the different configurations. If you have any other questions about this, shoot me a line.

Jake

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1986 Corvette Coupe, 415 CID, Edelbrock 6073s, ZZ9

 

Thanks for the replies. The main reason I asked is b/c somebody had said if the ratio was changed, the cam would not work as good as it was designed since it wasn't using the 1.5's. We'll try to choose between different ratios or just 1.6 all around. Thanks again.

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Erik '89 Formula 350 TPI
13.96 @ 97 on motor
12.83 @ 109 w/NOS
http://www.geocities.com/formulal98/

 

I had 1.6 rr's on both the intake and exhaust of my ZZ3. The idle was still very good. If you listened you could barely tell it had a larger cam than stock.

 

Go with the 1.6's across the board. I have them on my 305 with mods of course, but the idle is fine, not like stock, but it idles, I should have a vaccum canister though, it would help with the power brakes. So I'm sure your 350 can handle them.

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88'TA 305TPI 330HP, NATURALLY ASPIRATED, PASSES N.J. EMMISIONS. "I AM JUST THAT GOOD"