Finally: Holley to produce LT and True Dual System
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From: Marietta, GA
Car: 92 Z28
Engine: LS1
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Axle/Gears: 3.73 10 bolt
Re: Finally: Holley to produce LT and True Dual System
Haven't heard of anyone getting it installed on a running car yet. There are some clips on youtube of the fourthgen kit. Should be fairly close if you are running an LS.
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Car: 1982 Z-28
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Re: Finally: Holley to produce LT and True Dual System
Thanks, I just listened to some clips. Seems to be quieter than a Mufflex.
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From: Oyth
Car: 89RS vert
Engine: Erod
Transmission: 4L65e
Axle/Gears: BW, 3.27
Re: Finally: Holley to produce LT and True Dual System
Mines pretty quiet, but I do have dual cats per side.Even when crusing though it's not that loud.Only when I get on it does it wake up.
Last edited by 84 1LE; Mar 23, 2016 at 04:14 PM.
Re: Finally: Holley to produce LT and True Dual System
I bought this system with the headers and everything, but I decided to sell my car before installing if anyone is interested, I still have it all new in the box unopened.
http://chicago.craigslist.org/nwc/cto/5539634540.html
http://chicago.craigslist.org/nwc/cto/5539634540.html
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From: St Catharines
Car: 1987 IROC
Engine: LS1
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Re: Finally: Holley to produce LT and True Dual System
What's the general consensus on the exhaust system? Worth the coin? Any exhaust clips?
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From: Niles, IL
Car: '91 LS6/T56/9"
Engine: LS6
Transmission: T56
Axle/Gears: Currie 9"/4.11, detroit truetrac
Re: Finally: Holley to produce LT and True Dual System
Joined: Nov 2002
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From: Oyth
Car: 89RS vert
Engine: Erod
Transmission: 4L65e
Axle/Gears: BW, 3.27
Re: Finally: Holley to produce LT and True Dual System
I'm not complaining.Nothing on my car makes one think its nothing more than just a Camaro with GTA wheels.
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From: Indiana
Car: 92 Z28
Engine: ls3
Transmission: t56
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Re: Finally: Holley to produce LT and True Dual System
So I read through all of this thread and the one on ls1tech so im not sure if I missed it or not. But will the swap headers work with the 1 inch set back adapter plates and factory k-member? Trans-Dapt Performance Engine Swap Motor Mounts 4595 is what I used but with the 92 style motor mounts, not the ones shown in the link.
Re: Finally: Holley to produce LT and True Dual System
So I read through all of this thread and the one on ls1tech so im not sure if I missed it or not. But will the swap headers work with the 1 inch set back adapter plates and factory k-member? Trans-Dapt Performance Engine Swap Motor Mounts 4595 is what I used but with the 92 style motor mounts, not the ones shown in the link.
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From: Marietta, GA
Car: 92 Z28
Engine: LS1
Transmission: T56
Axle/Gears: 3.73 10 bolt
Re: Finally: Holley to produce LT and True Dual System
So I read through all of this thread and the one on ls1tech so im not sure if I missed it or not. But will the swap headers work with the 1 inch set back adapter plates and factory k-member? Trans-Dapt Performance Engine Swap Motor Mounts 4595 is what I used but with the 92 style motor mounts, not the ones shown in the link.
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From: Indiana
Car: 92 Z28
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Re: Finally: Holley to produce LT and True Dual System
Thanks guys i appreciate it, im going to give it a shot and see what happens. Worst case scenario they don't work and i have to return them. Ill post up my results here in a couple weeks.
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From: Indiana
Car: 92 Z28
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Re: Finally: Holley to produce LT and True Dual System
Still waiting on the headers to show up, hopefully it will be here soon. Its the last piece to get my car back together, but ill let everyone know the outcome.
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From: WINDSOR, CO
Car: 91 Z28, 87 SC, 90 IROC, 92 RS
Engine: LS1, 305 TPI, L98, NADA
Transmission: T56, 700r4's, and NADA
Axle/Gears: 3.89, 3.42, 3.23, NADA
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From: Middle of MI
Car: 1989 Trans Am GTA
Engine: Stock LS1
Transmission: T56
Axle/Gears: 3.70 9 bolt
Re: Finally: Holley to produce LT and True Dual System
Very nice looking! I'd love to redo mine for that extra ground clearance, my y-pipe goes under the trans x-member.
Re: Finally: Holley to produce LT and True Dual System
Damn, that's gorgeous... and the exhaust system is too! lol. I just sat here staring at your whole setup for a solid 10 minutes.
Last edited by R13_Braz; Jun 15, 2016 at 09:36 AM.
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From: WINDSOR, CO
Car: 91 Z28, 87 SC, 90 IROC, 92 RS
Engine: LS1, 305 TPI, L98, NADA
Transmission: T56, 700r4's, and NADA
Axle/Gears: 3.89, 3.42, 3.23, NADA
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From: Marietta, GA
Car: 92 Z28
Engine: LS1
Transmission: T56
Axle/Gears: 3.73 10 bolt
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From: WINDSOR, CO
Car: 91 Z28, 87 SC, 90 IROC, 92 RS
Engine: LS1, 305 TPI, L98, NADA
Transmission: T56, 700r4's, and NADA
Axle/Gears: 3.89, 3.42, 3.23, NADA
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From: Ottawa, Ontario
Car: 86 IROC
Engine: LQ4 6.0L
Transmission: T56
Axle/Gears: 3.55 8.8
Re: Finally: Holley to produce LT and True Dual System
Can someone measure and post up here the driveshaft u-joint angles at ride height after installing these motor mounts and T-56 cross member? Better yet, engine, driveshaft, and pinion angles.
For ride height , a measurement from the top of the axle tube to the frame would be good..to compare apples to apples.
Thanks in advance.
For ride height , a measurement from the top of the axle tube to the frame would be good..to compare apples to apples.
Thanks in advance.
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From: Indiana
Car: 92 Z28
Engine: ls3
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Re: Finally: Holley to produce LT and True Dual System
Well...they fit. Wasn't the easiest header install ive done, but the fit like a glove once in there. Other than having to undo the passenger side motor mount like the directions say. The only real issue i ran into was putting my starter in, didnt want to clear the headers and the stock fbody oil pan oil level sensor, but no biggy i got it to work. Ill post up some sound clips soon, ive got to do some tuning work for the heads and cam. But definitely a solid peice.
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From: Marietta, GA
Car: 92 Z28
Engine: LS1
Transmission: T56
Axle/Gears: 3.73 10 bolt
Re: Finally: Holley to produce LT and True Dual System
Daughter throwing in some commentary lol. This is with the Kooks headers, but the hooker duals. My phone seems to even out the sound so it doesn't peak, it is actually pretty loud, I'm also cammed and PP heads and a few other things.
Re: Finally: Holley to produce LT and True Dual System
Well...they fit. Wasn't the easiest header install ive done, but the fit like a glove once in there. Other than having to undo the passenger side motor mount like the directions say. The only real issue i ran into was putting my starter in, didnt want to clear the headers and the stock fbody oil pan oil level sensor, but no biggy i got it to work. Ill post up some sound clips soon, ive got to do some tuning work for the heads and cam. But definitely a solid peice.
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From: WINDSOR, CO
Car: 91 Z28, 87 SC, 90 IROC, 92 RS
Engine: LS1, 305 TPI, L98, NADA
Transmission: T56, 700r4's, and NADA
Axle/Gears: 3.89, 3.42, 3.23, NADA
Re: Finally: Holley to produce LT and True Dual System
Well...they fit. Wasn't the easiest header install ive done, but the fit like a glove once in there. Other than having to undo the passenger side motor mount like the directions say. The only real issue i ran into was putting my starter in, didnt want to clear the headers and the stock fbody oil pan oil level sensor, but no biggy i got it to work. Ill post up some sound clips soon, ive got to do some tuning work for the heads and cam. But definitely a solid peice.
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From: Indiana
Car: 92 Z28
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Axle/Gears: 4.11
Re: Finally: Holley to produce LT and True Dual System
toddoky, do you know what heads the headers are compatible with? Do they work with aftermarket heads that have plugs in different locations, or are they gm castings only?
Thanks,
Jay
Thanks,
Jay
Re: Finally: Holley to produce LT and True Dual System
I can't say what specific aftermarket heads they will work with, but they provide more spark plug clearance than any other headers I'm aware of...look closely at their bend geometry around the plugs and you can see that I invested a lot of effort to maximize clearance around every plug/boot.
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From: Indiana
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Re: Finally: Holley to produce LT and True Dual System
Ok thanks for the quick response. I didnt think there would be any issues, just wanted to check before i did anything.
Thanks
Thanks
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Car: 91Firebird Formula
Engine: 5.0 TBI / Now LS1
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Re: Finally: Holley to produce LT and True Dual System
Has anybody had any success with using there original driveshaft with this holly system?
Thanks,
Thanks,
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From: WINDSOR, CO
Car: 91 Z28, 87 SC, 90 IROC, 92 RS
Engine: LS1, 305 TPI, L98, NADA
Transmission: T56, 700r4's, and NADA
Axle/Gears: 3.89, 3.42, 3.23, NADA
Re: Finally: Holley to produce LT and True Dual System
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From: Vermont
Car: 91Firebird Formula
Engine: 5.0 TBI / Now LS1
Transmission: Auto / Now T56 with stage 2 monster
Axle/Gears: 4/10
Re: Finally: Holley to produce LT and True Dual System
Badnblk thanks for the info! I'm gearing up for my ls1 & t56 upgrade. Can't wait to get started. Love your set up for everything. Love the hooker exhaust!! I want the long tube but I may have to go with shorties to try and fit some small cats in next to the transmission. I would rather not!!
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From: WINDSOR, CO
Car: 91 Z28, 87 SC, 90 IROC, 92 RS
Engine: LS1, 305 TPI, L98, NADA
Transmission: T56, 700r4's, and NADA
Axle/Gears: 3.89, 3.42, 3.23, NADA
Re: Finally: Holley to produce LT and True Dual System
Badnblk thanks for the info! I'm gearing up for my ls1 & t56 upgrade. Can't wait to get started. Love your set up for everything. Love the hooker exhaust!! I want the long tube but I may have to go with shorties to try and fit some small cats in next to the transmission. I would rather not!!
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From: Marietta, GA
Car: 92 Z28
Engine: LS1
Transmission: T56
Axle/Gears: 3.73 10 bolt
Re: Finally: Holley to produce LT and True Dual System
This is with the Kooks to the Hooker. Pipe I made is basically just a small tight bend and maybe 4" of straight pipe to connect the two. Doubt it is enough room for a cat. If you want the long tubes you might as well get them since either way you will probably have to cut the exhaust up a bit to fit cats.
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From: WINDSOR, CO
Car: 91 Z28, 87 SC, 90 IROC, 92 RS
Engine: LS1, 305 TPI, L98, NADA
Transmission: T56, 700r4's, and NADA
Axle/Gears: 3.89, 3.42, 3.23, NADA
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From: Marietta, GA
Car: 92 Z28
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Axle/Gears: 3.73 10 bolt
Re: Finally: Holley to produce LT and True Dual System
I think bullet cats could be worked in next to the trans?
[IMG]http://i808.photobucket.com/albums/zz6/BADNBLK91/camaro/LS1%20swap/20160611_143935_zpswakug7dt.jp
[IMG]http://i808.photobucket.com/albums/zz6/BADNBLK91/camaro/LS1%20swap/20160611_143935_zpswakug7dt.jp
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From: Vermont
Car: 91Firebird Formula
Engine: 5.0 TBI / Now LS1
Transmission: Auto / Now T56 with stage 2 monster
Axle/Gears: 4/10
Re: Finally: Holley to produce LT and True Dual System
Thanks guys for the info! I have decided to get the long tubes along with the rest of the system, mounts, cross member, exhaust. I like that there is a system that all works together. Do you know if Holly has had in the past a Labor day sale? I would love to buy the whole kit at one shot and if I could save a little that would be awesome!!
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From: Vermont
Car: 91Firebird Formula
Engine: 5.0 TBI / Now LS1
Transmission: Auto / Now T56 with stage 2 monster
Axle/Gears: 4/10
Re: Finally: Holley to produce LT and True Dual System
Toddoky thank you for all your post hear and on the ls1 tech forums! It is great to have an insider that can help us with our builds and teas us with a really nice system!!
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From: WINDSOR, CO
Car: 91 Z28, 87 SC, 90 IROC, 92 RS
Engine: LS1, 305 TPI, L98, NADA
Transmission: T56, 700r4's, and NADA
Axle/Gears: 3.89, 3.42, 3.23, NADA
Re: Finally: Holley to produce LT and True Dual System
You've accomplished great end results with your car and the Hooker Blackheart decals look awesome on the quarter panels...congratulations on the award!
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From: Atlantic Canada
Car: 87 Trans Am
Engine: LS1
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Re: Finally: Holley to produce LT and True Dual System
Whats the sound like when you're decelerating from higher rpm while in gear and not on the brakes? My Dynomax LM1 copy has a noise I hate in that situation around 2500rpm... And I want to build my own exhaust system similar to this.
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From: Indiana
Car: 92 Z28
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Re: Finally: Holley to produce LT and True Dual System
Hey Toddoky, is there an individual part number for the mufflers that come with the true dual exhaust kit?
Re: Finally: Holley to produce LT and True Dual System
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From: MA
Car: 1982 Z-28
Engine: 383
Transmission: Turbo 350
Axle/Gears: Det. Posi, Superior Axles, 3:73 G
Re: Finally: Holley to produce LT and True Dual System
Do you think the 70501426RHKR will be avail soon? I see it's backordered.
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From: West Warwick RI, postal code: 02893
Car: Building LS3, T56 Z28
Engine: LS3
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Re: Finally: Holley to produce LT and True Dual System
toddoky - Any idea what the flow rate is thru the true dual Black Heart system is?
I want to install this on my 390 SBC with an F1 Procharger pushing about 14psi. This should net me near the 700 HP mark and I want to make sure this has enough flow to support that. I think it does, but thought it would be nice to see if you guys over at Hooker had some hard numbers on flow to to along with the system.
Thanks for any help that you can provide.
I want to install this on my 390 SBC with an F1 Procharger pushing about 14psi. This should net me near the 700 HP mark and I want to make sure this has enough flow to support that. I think it does, but thought it would be nice to see if you guys over at Hooker had some hard numbers on flow to to along with the system.
Thanks for any help that you can provide.
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From: Davison, MI
Car: 89 Camaro
Engine: Dart SHP 400-Holley Terminator EFI
Transmission: Tremec T56 Magnum F
Axle/Gears: Strange S60 3.55:1
Re: Finally: Holley to produce LT and True Dual System
toddoky - Any idea what the flow rate is thru the true dual Black Heart system is?
I want to install this on my 390 SBC with an F1 Procharger pushing about 14psi. This should net me near the 700 HP mark and I want to make sure this has enough flow to support that. I think it does, but thought it would be nice to see if you guys over at Hooker had some hard numbers on flow to to along with the system.
Thanks for any help that you can provide.
I want to install this on my 390 SBC with an F1 Procharger pushing about 14psi. This should net me near the 700 HP mark and I want to make sure this has enough flow to support that. I think it does, but thought it would be nice to see if you guys over at Hooker had some hard numbers on flow to to along with the system.
Thanks for any help that you can provide.
https://www.thirdgen.org/forums/exhaust/732243-hooker-blackheart-exhaust.html#post6035112
He answered this there. This won't support your setup.
Last edited by Lurbie; Nov 10, 2016 at 12:52 PM.
Re: Finally: Holley to produce LT and True Dual System
Thanks for that Lurbie. I hadn't come across that thread before now.
Although he does offer an answer by way of comparison, it would be interesting to know how exactly he arrived at his conclusion. Being in his position he undoubtedly has access to all sorts of flow data regarding the CFM of his engineering efforts. And I would like to see them.
Short of that, it's a matter of taking the man at his word (and an educated, engineering word I should add) and go from there.
Fortunately for me, I don't have the same need as Dennis does. Or unfortunately depending on how you compare the two situations. I'm at best, about 450 HP.
Thanks again Lurbie.
Although he does offer an answer by way of comparison, it would be interesting to know how exactly he arrived at his conclusion. Being in his position he undoubtedly has access to all sorts of flow data regarding the CFM of his engineering efforts. And I would like to see them.
Short of that, it's a matter of taking the man at his word (and an educated, engineering word I should add) and go from there.
Fortunately for me, I don't have the same need as Dennis does. Or unfortunately depending on how you compare the two situations. I'm at best, about 450 HP.
Thanks again Lurbie.
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From: PA
Car: 91/89/85/82 Z28s, 88 TA, 88/88 SC
Engine: SBC and LS variations
Re: Finally: Holley to produce LT and True Dual System
so quick question regarding UMI tubular k-member... has anyone used the holley ls swap parts yet with this k-member?
my son and i are going to swap out his sbc for an ls3 in his formula that already has the umi k-member installed.
the holley motor mounts utilize mounting holes on the factory k member that normally where for the v6 in some spots vs the forward v8 holes... on the umi k-member the pad only was made for the v8 holes... i can fab something up, just wondering if anyone else has done this yet
i am thinking about taking the umi lsx mount adapter and basically grinding off their existing mount arms and fabricating arms to weld in the right spot...
my son and i are going to swap out his sbc for an ls3 in his formula that already has the umi k-member installed.
the holley motor mounts utilize mounting holes on the factory k member that normally where for the v6 in some spots vs the forward v8 holes... on the umi k-member the pad only was made for the v8 holes... i can fab something up, just wondering if anyone else has done this yet
i am thinking about taking the umi lsx mount adapter and basically grinding off their existing mount arms and fabricating arms to weld in the right spot...
Re: Finally: Holley to produce LT and True Dual System
Spohn kmember and motor mounts, with hooker crossmember. Redesigning my exhaust myself in my garage, not too bad imho.
Way better than anything else offered on the market right now. Worth the $300
Way better than anything else offered on the market right now. Worth the $300



















