Secondary Throttle Removal - ZR-1 Net Registry Forums

bobbyhi · 01-21-2011

I'm bringing my '90 down to Marc's on the 23rd of April and leaving it for a week for some minor things. I have been toying with the idea of removing the secondarys. Good idea?? Bad idea?? What say you guys??????

Pete · 01-21-2011

You'll notice it'll pull/drive away from a stop nicer.

No more looking for vacuum leaks,actuators,solonoids,pump,vacuum lines,ect.

Pete

ZR1@gmx.com · 01-21-2011

Quote:

Originally Posted by bobbyhi

I'm bringing my '90 down to Marc's on the 23rd of April and leaving it for a week for some minor things. I have been toying with the idea of removing the secondarys. Good idea?? Bad idea?? What say you guys??????

I removed mine and I am glad I did! It is a new engine so it runs much better and can not tell if it is because of the secondary removal or not... nice not to have to worry about all that stuff working and not leaking!
Love it!

-=Jeff=- · 01-22-2011

Bob,

is it a drop and run? are you driving or flying back?

April 23rd is a Sat.. Wanna meet some of the FBI Boys then or on the pick-up trip or BOTH?

Paul Workman · 01-22-2011

Quote:

Originally Posted by bobbyhi

I'm bringing my '90 down to Marc's on the 23rd of April and leaving it for a week for some minor things. I have been toying with the idea of removing the secondarys. Good idea?? Bad idea?? What say you guys??????

I've got nothing but good to say about removing mine. I have Marc's chip in mine, also dolled up with fan temp control, modified idle, and some other stuff. It runs soooo sweat (ask him when you see him).

That's why I was a little bit shocked when Marc's recommendation, given at his talk at the ZR-1 gathering in BG last year, was to leave the secondaries in. He described how and when the secondaries open, and how to manipulate them while drag racing and cruising. But, in my experience it is more responsive and the over all driveability is sooo nice, not to mention not having to ever worry about the overly complicated system crapping out ever again, that it made me shake my head in disbelief when he said that...

Parts not used don't fail and they don't cost much to fix!

Anywayz...When you come down, and if you have the time, we'll have an FBI pizza GTG, drink some brewskies and tell some lies!

P.

GOLDCYLON · 01-22-2011

It would be great is somebody has written a step by step on how to do this. Im surprised the SES light dosent come on with everything removed. GC

ZR1@gmx.com · 01-22-2011

Quote:

Originally Posted by GOLDCYLON

It would be great is somebody has written a step by step on how to do this. Im surprised the SES light dosent come on with everything removed. GC

I can write that and document it with photos... Probably be a week before I can get to it. It is fairly easy, I made a small tool that helped.

Mark H programed a chip for that and several other mods, I think that may be a requirement.

bobbyhi · 01-22-2011

FBI boys - I will be at Marc's on Saturday April 16th. He opens at 10:30AM. My flight back leaves Midway at 2:58 PM. I come back the next Saturday the 23rd arriving at Midway at 8:30AM. Would be great to get together one day or both days. Always happy to meet fellow ZR-1ers. I'm not sure how far Marc is from Midway but the taxi would have to pick me up a couple of hours before flight time for the 16th. The only fly in the ointment is that I might have a co-pilot

.......

-=Jeff=- · 01-22-2011

Quote:

Originally Posted by bobbyhi

FBI boys - I will be at Marc's on Saturday April 16th. He opens at 10:30AM. My flight back leaves Midway at 2:58 PM. I come back the next Saturday the 23rd arriving at Midway at 8:30AM. Would be great to get together one day or both days. Always happy to meet fellow ZR-1ers. I'm not sure how far Marc is from Midway but the taxi would have to pick me up a couple of hours before flight time for the 16th. The only fly in the ointment is that I might have a co-pilot

.......

Taxi will be a bit of $$ to go to midway

I think on the return trip \it would be a bit better as you would not be time limited..

Paul Workman · 01-23-2011

Quote:

Originally Posted by GOLDCYLON

It would be great is somebody has written a step by step on how to do this. Im surprised the SES light dosent come on with everything removed. GC

Ah! It would, 'cept the ECM is re-programmed to accept zero vacuum as being OK, and the vacuum sensor, tho open now to the atmosphere, remains electrically connected (so the ECM knows it's there). So, having the chip modified is part of the gig.

When I had my chip re-programmed, it was part of a top end P&P and I opted to have the cooling fans & the idle characteristics (among some other features) included in the cal.

FYI, at idle, Marc's "no secondary throttle plates" calibration has the secondary injectors turned off. At 1 degree of throttle and above, the secondaries join the primaries and hello throttle response!

Pete is a "two-finger" typer, so he's skilled at packing it all in so few words. Gotta love 'im.

Quote:

Originally Posted by Pete

You'll notice it'll pull/drive away from a stop nicer.

No more looking for vacuum leaks,actuators,solonoids,pump,vacuum lines,ect.

Pete

Although this pic was taken to document a problem with a gasket, one can see the hole left by the secondary throttle shaft in the secondary port. (And, one can see how the bosses have been "modified" around the injectors (1990 LT5), but that is another topic.)

P.

01-21-2011	#1
bobbyhi Join Date: Jul 2005 Location: Mendota Heights, MN. 55120 Posts: 983	Secondary Throttle Removal I'm bringing my '90 down to Marc's on the 23rd of April and leaving it for a week for some minor things. I have been toying with the idea of removing the secondarys. Good idea?? Bad idea?? What say you guys??????

01-21-2011	#2
Pete Join Date: Dec 2003 Location: Chicagoland,IL Posts: 2,667	Re: Secondary Throttle Removal You'll notice it'll pull/drive away from a stop nicer. No more looking for vacuum leaks,actuators,solonoids,pump,vacuum lines,ect. Pete __________________ '91 #1635 PoloGreen 350 LT5 11.09 @ 129.27 11.04 @ 128.86 474RWHP 400RWTQ http://www.youtube.com/watch?v=SFNFOhGGlR4 http://www.youtube.com/watch?v=ZlRIOMwaDYY https://sites.google.com/site/peteszr1garage Last edited by Pete; 01-22-2011 at 03:35 AM.

01-22-2011	#4
-=Jeff=- Join Date: Jul 2007 Location: Bartlett, IL Posts: 7,156	Re: Secondary Throttle Removal Bob, is it a drop and run? are you driving or flying back? April 23rd is a Sat.. Wanna meet some of the FBI Boys then or on the pick-up trip or BOTH? __________________ 1990 Corvette ZR-1 #1051 Watson Headers (2" Primary) - Flowmaster Cats - Borla Catback Late Model IH - Plenum Coilovers - 4.10s Shelby Series 1 - Wilwood Brakes Custom Interior NCM Lifetime Member #978

01-22-2011	#6
GOLDCYLON Join Date: May 2007 Location: Peoria, AZ Posts: 9,120	Re: Secondary Throttle Removal It would be great is somebody has written a step by step on how to do this. Im surprised the SES light dosent come on with everything removed. GC __________________ GOLDCYLON - 91 ZR-1 #2014 GOLDCYLON - 90 ZR-1 #2794, 4L60e (Formerly Schrade's) GOLDCYLON - 11 CTS-V Arizona State Director 91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat 90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat 11 RED/GREY CTS-V

01-22-2011	#8
bobbyhi Join Date: Jul 2005 Location: Mendota Heights, MN. 55120 Posts: 983	Re: Secondary Throttle Removal FBI boys - I will be at Marc's on Saturday April 16th. He opens at 10:30AM. My flight back leaves Midway at 2:58 PM. I come back the next Saturday the 23rd arriving at Midway at 8:30AM. Would be great to get together one day or both days. Always happy to meet fellow ZR-1ers. I'm not sure how far Marc is from Midway but the taxi would have to pick me up a couple of hours before flight time for the 16th. The only fly in the ointment is that I might have a co-pilot.......