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Old 05-11-2013   #101
tpepmeie
 
Join Date: Aug 2005
Location: Fishers, IN
Posts: 815
Default Re: 427 Assembled

So, I took the car back to the DynoJet today. Actually, two DynoJets, one in the morning and one in the afternoon to confirm.

Hit 638rwhp (SAE) in the morning session. 548 rwtq.

I cannot get enough fuel in it from 5000-6500... no matter what I try, the AFR is 13.5:1. Fuel Pressure is OK, but no amount of change to the fuel table will fatten it up. Conclusion I am drawing is that the injectors are maxed out.

They were allegedly 26lb'ers, but I don't think that can be. Will have them tested, and probably go for 30's next time. I even changed the table offset to try to gain fuel, but wouldn't budge.

The afternoon session on the other side of town was 634 rwhp, with water temps over 200F. So I am pretty comfortable that the morning session is accurate (also made that number last August). It seems to be consistently at this number.

Will post the sheets and maybe a vid later.

Todd
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Old 05-11-2013   #102
XfireZ51
 
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,708
Default Re: 427 Assembled

Todd,

Sounds like injectors are static. Have u confirmed DC% at WOT?
Also, not sure which injectors you are using but you might check the injector bias tables to see if they match the injector spec. Granted that will make greater diff at lower rpm but it just might give u enough headroom to bring AFR down.
Try increasing them 10-20% and see what happens.
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Old 05-11-2013   #103
Schrade
 
Join Date: Dec 2012
Location: NC
Posts: 1,786
Default Re: 427 Assembled

YiKEs!!!

Pretty big twister!

Looks like you're gonna' need the ZR12 Falconer with extended wheelbase to shoehorn it in!!!
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I'm getting my snappics / threads removed blindly as fast as I can, to get in compliance with copyright / license TOS on the boards here (lots of FSM pages and other copyright / license violations on my part; sorry guys). And thanks to all the guys who didn't whine when I posted those FSM copyrighted / licensed stuff in my threads...

( :thumbsup: [b]and to think I complied with a mod's request to delete a pic of him in a Challenge Car in NCM Museum, so he wouldn't get in hot water)[/b]

Thanks to several guys here for sending parts FREE; BearlyFlying, WeGone, Geezer, GoldCylon, and more there, TonyD, mike100, fletchusmc...

1990 #2794; 4L60e Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless, Power Effects 3"

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Old 05-11-2013   #104
XfireZ51
 
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,708
Default Re: 427 Assembled

Todd,

Sorry. Just re-read ur post and saw that you had tried the Inj Offset, correct?
Or was that the VE offset.
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Former ZR-1 Registry - BOD
1972 Corvette 4speed base Coupe SOLD long time ago
1984 Corvette Z-51/4+3 SOLD
1992 Corvette ZR-1 Aqua/Gray #474 SOLD
1992 Corvette ZR-1 Black Rose/Cognac #458
2014 Honda VFR Interceptor DX
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Old 05-11-2013   #105
cvette98pacecar
 
Join Date: May 2011
Location: Sydney, Australia
Posts: 2,479
Default Re: 427 Assembled

Quote:
Originally Posted by tpepmeie View Post
So, I took the car back to the DynoJet today. Actually, two DynoJets, one in the morning and one in the afternoon to confirm.

Hit 638rwhp (SAE) in the morning session. 548 rwtq.

I cannot get enough fuel in it from 5000-6500... no matter what I try, the AFR is 13.5:1. Fuel Pressure is OK, but no amount of change to the fuel table will fatten it up. Conclusion I am drawing is that the injectors are maxed out.

They were allegedly 26lb'ers, but I don't think that can be. Will have them tested, and probably go for 30's next time. I even changed the table offset to try to gain fuel, but wouldn't budge.

The afternoon session on the other side of town was 634 rwhp, with water temps over 200F. So I am pretty comfortable that the morning session is accurate (also made that number last August). It seems to be consistently at this number.

Will post the sheets and maybe a vid later.

Todd
Sweeeeet C4 ZR-1 638 RWHP, C6 ZR1 638 CHP.
Once Again...... Sweeeeeet.
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Old 05-11-2013   #106
XfireZ51
 
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,708
Default Re: 427 Assembled

Todd,

There's a spot available at the Chicago 1/2mile shootout this June. Not far from the Indy area.
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Former ZR-1 Registry - BOD
1972 Corvette 4speed base Coupe SOLD long time ago
1984 Corvette Z-51/4+3 SOLD
1992 Corvette ZR-1 Aqua/Gray #474 SOLD
1992 Corvette ZR-1 Black Rose/Cognac #458
2014 Honda VFR Interceptor DX
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Old 05-11-2013   #107
cvette98pacecar
 
Join Date: May 2011
Location: Sydney, Australia
Posts: 2,479
Default Re: 427 Assembled

Quote:
Originally Posted by XfireZ51 View Post
Todd,

There's a spot available at the Chicago 1/2mile shootout this June. Not far from the Indy area.
Dom, I think Ronstar was looking for a spot.
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[SIGPIC][/SIGPIC]
[COLOR=blue]G[/COLOR][COLOR=red]rand[/COLOR] [COLOR=blue]S[/COLOR][COLOR=red]port[/COLOR] Registry Lifetime Member
NCM Lifetime Member #2655
Pacecar Registry Member
[COLOR=red]ZOOM Charter Member - ZR-1 Owners of Michigan[/COLOR]
[COLOR=plum][I]ZR-1[/I] Registry member since 2012 [/COLOR]
[COLOR=black]1990 LPE "368" Aerobody ZR-1, Last ZR-1 built by John[/COLOR]
1991 Callaway Aerobody ZR-1, DRM 500
1991 Shinoda Aerobody Spyder,
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Old 05-11-2013   #108
XfireZ51
 
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,708
Default Re: 427 Assembled

Contact Blake Hutchinson at wannagofast.com. I believe any spots available revert back to wgf and there's a waiting list. Ronstar should try there.
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[SIGPIC][/SIGPIC]Former Membership Chairman
Former ZR-1 Registry - BOD
1972 Corvette 4speed base Coupe SOLD long time ago
1984 Corvette Z-51/4+3 SOLD
1992 Corvette ZR-1 Aqua/Gray #474 SOLD
1992 Corvette ZR-1 Black Rose/Cognac #458
2014 Honda VFR Interceptor DX
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Old 05-11-2013   #109
tpepmeie
 
Join Date: Aug 2005
Location: Fishers, IN
Posts: 815
Default Re: 427 Assembled

Quote:
Originally Posted by XfireZ51 View Post
Todd,

Sorry. Just re-read ur post and saw that you had tried the Inj Offset, correct?
Or was that the VE offset.

Tried several things, including the VE table offset. These injectors must be very small--VE table is maxed at 140, which clearly is only a band-aid fix to get enough fuel. It's like 13.5 afr from 4700 rpm to 6500. I think there is some more power in it with more tuning.

BTW, for those interested in how much the MAT timing retard affects these motors...on one run the motor was heat soaked and we forgot to turn the external cooling fan on, and it took about 3d spark advance out. Killed it by 20-25 ft-lbs across the board. I zero'd that table, put the fans back on and instantly got it back on the next run.
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Old 05-11-2013   #110
tpepmeie
 
Join Date: Aug 2005
Location: Fishers, IN
Posts: 815
Default Re: 427 Assembled

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