It kicks butt! Even with speed density! Now let me warn that I have lots of mods done to my car, TPIS base/runners, ported L98 aluminum heads, SLP 1 3/4" headers, 1.5 roller rockers, etc. I wouldnt put this cam in a stock TPI car. When we first fired up the engine, it idled like crap and had that lumpy cam sound. We had to open the throttle blades almost all the way, so it idled at 1200 RPMs, to get it to stay alive. Then I had a quick and dirty PROM burned for it, and it idled better but still wasnt right... However, after resetting the TPS and IAC, adjusting the throttle blades, setting the timing at stock 6º, and adjusting the fuel pressure up to 48lbs, the idle smoothed out. Now it purrs like a kitten, smooth as glass. You can hardly tell its got a big cam in there, at idle. And when I step on the gas, the tires scream for traction. I've spent the weekend with my Diacom and PROM-burning friend getting the idle dialed in correctly in regards to the fuel and timing. I just filled up the gas tank today so we'll see how well its gas mileage is. And this weekend I'm going to the track, hoping for a 12.90 run. Call me a wuss, but I still havent hit WOT with it yet. I have taken it over 5000 RPMs at part throttle, where it felt like it was still pulling. We'll see. I'm getting my own PROM burning equipment soon too.

I forgot to say, when we first started it up and it idled bad, we put a vacuum gauge on it. It read 11". After adjusting everything, its now up to 17". Amazing...

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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=-

[This message has been edited by Kevin91Z (edited February 26, 2001).]

 

Great Kevin. I can't wait to get mine back together. I'm still waiting on the Pro Magnum RRs and trying to deside on a torque converter. Good luck.



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Bob '89 Formula CC350
Last(lost)Member of the Elusive Great Lakes Crew
My car's homepage

 

good luck with your car kevin.got any pictures of the car and motor?whats your opinon on a set of world products 305 s/r's on a 5.7 tpi motor with a ZZ4 cam and 1.6 RR's?the heads have 171cc intake runners,58cc chambers,1.94 and 1,5 valves.do you think that will be too much cam?i have headers and full mandrel bent pipes,i've ported my stock tpi base and plenum.

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1991 banditt2 #130 of 600 http://clubs.yahoo.com/clubs/streetdawgracing http://y42.photos.yahoo.com/tonysams72. http:/discussion-board.com/GreaterCincinnatiFBodyAssociation

 

world products 305 s/r's on a 5.7 tpi motor wouls be terrible move, the compression ratio would be too high for the iron heads. The stock compression on the 91 5.7L is 9.75 to 1. If you bolt these heads on you would get severe detonation and no power because the knock sensor would constantly be retarding the timimg, unless ytou use 5$ a gallon race fuel.

9.8 to 1 is the limit for compression with IRON heads. Up 11:1 with aluminum. Besides, for a litte less you caould probably get a set of corvette aluminum heads and run the highr copmression, with the same flow #'s as teh torquers.

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Hybrid Black 5.7L 5 Speed
'95 Competition Yellow Corvette Coupe ZF6

 

That's good vacuum. Running 1.6:1 rockers my MAF setup pulls 14"Hg and idles kinda choppy.

I'm considering downgrading to 1.5:1 rockers this season after I get a baseline with the new runners and injectors.

-the other Kevin

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1982 Z-28

See http://www.mycar.net/mafb/registry/detail.cfm?id=276 for details

 

I'm glad you like it Kevin, I know I do mine. My car also idles perfectly smooth, but only in closed loop. In open loop it surges up and down to stay alive, but I'm slowly working that out with PROM tuning.

I think the cam really does keep pulling up to 5000 rpm too (haven't gone beyond yet), even with the stock TPI on top. I haven't gotten a good ET yet due to traction problems (2.41 60' ), but I did have a 103 MPH trap speed with my setup two weeks ago. I'm hoping to go on Friday and see a 13.3 or so.

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Black 88 GTA L98
261 RWHP, 345 RWTQ
ZZ4 bottom end, Edelbrock 6085 heads, LT4 HOT cam, GMPP 1.6 RR's, ported stock TPI, SLP 1 3/4" headers, no cat, Dynomax cat-back, Stock PROM
E.T.F.A Member #11

 

the motor is from 89 GTA. the stock Compression ratio is 9.3 to 1. with those W/P heads and a 58cc combustion chamber what would that bring it too.

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1991 banditt2 #130 of 600 http://clubs.yahoo.com/clubs/streetdawgracing http://y42.photos.yahoo.com/tonysams72. http:/discussion-board.com/GreaterCincinnatiFBodyAssociation

 

i called WORLDCASTINGS and they told me my compresion would around 9.8 to 1

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1991 banditt2 #130 of 600
Project 350 Banditt
<A HREF="http://clubs.yahoo.com/clubs/streetdawgracing" TARGET=_blank>
http://clubs.yahoo.com/clubs/streetdawgracing</A>
http://y42.photos.yahoo.com/tonysams72.
http:/discussion-board.com/GreaterCincinnatiFBodyAssociation

 

What did you run that weekend kevin?

James

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1985 Z-28 305 TPI
221,000+ mi., Original Eng.

 

I didnt get to run until March 31st, and the car was way lean on the top end, and pinging all the way. I swapped the 22lb injectors to LT1 24lbs, but I dont know when I can go back to the track. I'll post it on the SoCal board so you'll know.


------------------
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=-

 

Kevin:

Can you tell me what the cam specs are on your motor? Is the 17" vacuum reading taken in gear or in park? What is your idle speed rpm? Thanks alot

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Dave Zelinka

 

I have a 5-speed, there is no "in gear" or "park". Those readings are in neutral with idle set to about 850 RPMs.

The cam is the regular LT4 HOT cam, specs are 218/228, .492/.492 lift and 112 LSA. I have 1.52 rockers on it so the lift is .498/.498. When I degreed my cam I found it was 3 degrees retarded so I put a 4 degree advance key in.

 

3 degrees retarded????? I have talked to quite a few people with that cam and I haven't heard any of them say anything about it being retarded from the manufacturer. This is a dumb question but, are you sure you degreed it correctly????

I am planning on using this cam as well so I would like to know what the deal is with it.

thanks,

 

Thanks Kevin. I wanted to compare to my motor I just finished. It is a 383 tpi. I pull 18" vacuum at 750rpm idle in "park or neutral" I have a 204/214 deg cam with 112 lobe separation, .425/.455 lift with 1.5:1 rockers. With your cam, your vacuum sounds real good for a 350. I think my vacuum is just so-so for a 383 with the mild cam I have.

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Dave Zelinka

 

What did you end up doing w/ your ZZ4 cam Kevin?


James

 

Matt, I got the cam used from an Impala SS so I dont know whats up with it. My dad is a professional mechanic and racer for the past 40+ years, so yes we degreed it in correctly. We couldnt believe it either so we did it twice.

James, the ZZ4 cam is going into my dad's TPI engine, with Vortech heads, as soon as Scoggin Dickey releases the intake manifold.