Register or Log In To remove these advertisements. |
|
|
|
Thread Tools | Display Modes |
|
02-04-2011, 08:28 PM | #1 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
LS376 / 480 With 4L80E
Hey Guys,
Just got my LS376 in, and already have the 4L80E in the truck. I went to install the GM p/t #12602448 flex plate to my torque converter and it didn't quite match up. The holes on the flex plate are about a 1/8 to 1/4 of an inch in from lining up. Any idea of how to proceed? Should I get a different flex plate or would it be possible to 'open' the holes up in order to for both pieces to line up? Thanks
__________________
RCC |
02-04-2011, 09:06 PM | #2 |
Senior Member
Join Date: Mar 2002
Location: Temple, Ga
Posts: 854
|
Re: LS376 / 480 With 4L80E
You can open them up as long as the crankshaft to torque converter spacing is right. All of the 4l80e flex plates I have seen are 6 bolt you may want to double check.
|
02-04-2011, 09:13 PM | #3 |
Senior Member
Join Date: Apr 2000
Location: Delta,Pa
Posts: 14,948
|
Re: LS376 / 480 With 4L80E
Its the wrong flex plate for a 4l80e. A 4l80e has 6 bolts.
__________________
Owner of North Point Car Care in Dundalk Md. We specialize in custom exhaust on both modern and classic vehicles. We are a full service auto shop from classics to modern vehicles. Feel free to contact me with questions. I will give a 10% discount to any board member. |
02-04-2011, 09:13 PM | #4 |
Senior Member
Join Date: May 2009
Location: Fort Worth, TX
Posts: 6,370
|
Re: LS376 / 480 With 4L80E
The holes not lining is not the real problem, The "snout" on the 4L80E converter is not long enough to engage into the crankshaft.
This is what GM uses to mate a 4L80E to a LS engine http://www.gmpartsdirect.com/results...umber=12621399 & the only Flexplate that I know of that will work with your 6-bolt converter Heres another thread on the subject http://67-72chevytrucks.com/vboard/s...d.php?t=426994 Last edited by clinebarger; 02-21-2011 at 12:44 AM. |
02-05-2011, 11:55 AM | #5 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
Thanks guys, I'll post pics of the motor and install once I get the new plate and spacer.
__________________
RCC |
02-06-2011, 12:16 AM | #6 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
So I pulled the flex plate that came on the motor. It matched the one sold to me that I was told would bolt right up to the 4L80E, go figure. Hopefully the GM dealer will be a nice guy and swap me out for this one; GM part number 12621399
__________________
RCC |
02-09-2011, 11:25 PM | #7 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
Got my flex plate in and looks good.... I need to grab some more bolts tomorrow to bolt up the converter though. Do you guys recommend using washers, lock washers, or just loctite? Also, the GM specs recommend bolting the flex plate to crank at 74 ft/lbs. Does that sound right to everyone?
__________________
RCC |
02-10-2011, 06:20 PM | #8 |
Senior Member
Join Date: May 2009
Location: Fort Worth, TX
Posts: 6,370
|
Re: LS376 / 480 With 4L80E
You need the correct torque converter bolts, New ones will have threadlocker already applied to them, Like these http://www.autozone.com/autozone/acc...er=732339_0_0_
Torque converter bolt torque is 32 ft. lbs 74 ft. lbs. is the final torque on the flexplate bolts, Heres the entire procedure. First Pass...20 Nm (15 ft. lbs.) Second Pass...50 Nm (37 ft. lbs.) Final Pass...100 Nm (74 ft. lbs.) Be sure to apply thread sealant to them, I use this http://www.permatex.com/products/aut...ad_Sealant.htm Last edited by clinebarger; 02-13-2011 at 09:28 PM. |
02-12-2011, 01:23 PM | #9 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
clinebarger, thanks bud. When I was doing final pass I started to turn the motor over. I suppose I should place a bar stop through the fly wheel to tighten. I really hate to over tighten these bolts into the crank though. Any words of wisdom....
__________________
RCC |
02-13-2011, 08:10 PM | #10 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
Motor fits very well. Installed converter then dropped in the motor. Once all the bolts were nice and snug I went to go bolt up the converter to the flex plate. When I checked it out it had perfect clearance, about a 1/16". Hopefully I can get some headers picked out soon. I will be ordering the Concept One accessory set, and a computer from Speartech very soon.
Any word on the Doug Thorley "big tube" headers. From what I've read I should try to run at least a 1 & 5/8" header.
__________________
RCC |
02-21-2011, 12:28 AM | #11 |
Registered User
Join Date: Jan 2008
Location: Las Vegas, Nv
Posts: 954
|
Re: LS376 / 480 With 4L80E
I assume you have L92 or LS3 heads on there. I don't know the cam specs but to pump out 480hp out of 376ci it's probably got a lot of lift and duration. Most people making that kind of power are running headers with at least 1 3/4" primaries and 3" collectors. I think any smaller and you'll be choking off horsepower. Doug Thorley has been talking about making some swap headers with larger primaries using the 324y for a template, but I haven't seen them yet. They're supposedly in the prototype/testing phase. There's a thread on it here with someone from DT talking about it. Dynatech swap headers for 70-81 camaros are being used and they're around $400 coated. They hang down a few inches below the frame but other than that I can't see any drawbacks. Good luck with your swap.
__________________
http://67-72chevytrucks.com/vboard/s...54#post3194654 |
02-21-2011, 12:30 AM | #12 |
Registered User
Join Date: Jan 2008
Location: Las Vegas, Nv
Posts: 954
|
Re: LS376 / 480 With 4L80E
__________________
http://67-72chevytrucks.com/vboard/s...54#post3194654 |
11-19-2011, 11:13 PM | #13 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
Hey guys, anyone have any insight or suggestions on what accessory drive kit to run? I am trying to decide between Concept One and Billet Specialties Tru Trac. Also, if there are any other products I'm always open ears. Thanks
__________________
RCC |
11-22-2011, 03:15 AM | #14 | |
Collector of Projects
Join Date: Apr 2003
Location: Las Vegas
Posts: 3,106
|
Re: LS376 / 480 With 4L80E
Quote:
http://s41657.storefront-solutions.c...?CategoryID=38 |
|
02-03-2012, 07:48 PM | #15 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
Got some new hardware today. Hopefully will get them on tomorrow.
__________________
RCC |
02-03-2012, 11:23 PM | #16 |
Has more rust than truck...
Join Date: Apr 2005
Location: Ivanhoe, MN
Posts: 2,421
|
Re: LS376 / 480 With 4L80E
Wow, those are purdy! Sure look more beefy than the smaller DT's too.
|
02-04-2012, 06:51 PM | #17 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
They are beefy and they DON'T fit. To bad...
__________________
RCC |
02-04-2012, 07:12 PM | #18 |
Still Just Havin Some Fun!
Join Date: Jun 2007
Location: Piedmont, Oklahoma
Posts: 1,145
|
Re: LS376 / 480 With 4L80E
say what? Are they the new larger swap headers?
__________________
a green one with some stuff done to it.... |
02-04-2012, 10:46 PM | #19 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
Yep. The right side (when sitting in the truck) hit in the rear; on the firewall. I have a Porterbuilt Dropmember which moves the motor back. I really thought they'd fit.
__________________
RCC |
02-04-2012, 11:46 PM | #20 |
Has more rust than truck...
Join Date: Apr 2005
Location: Ivanhoe, MN
Posts: 2,421
|
Re: LS376 / 480 With 4L80E
Sorry to hear that. Does the dropmember just move the motor back or back and up?
|
02-04-2012, 11:49 PM | #21 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
Back and Up. Now that I'm looking at the headers; the rear passenger tube goes way back when it should just go down and flow like the driver side. Oh well...
__________________
RCC |
02-05-2012, 02:04 AM | #22 |
Truck and auto performance nut
Join Date: Feb 2007
Location: McKinney,Texas
Posts: 3,848
|
Re: LS376 / 480 With 4L80E
looks like that #6 tucking behind #8 adds a couple inches. The Dynatech's don't do that.
and I'd think you need at least a 1 3/4" primary or even 1 7/8", w/3" collector or larger. I've even started seeing LSx headers with big block sized 2" primaries!
__________________
Kurt - '68 GMC short step - NIB '09 LY6 6.0L crate motor w/mods, NIB '12 crate 4L85e w/billet 3k stall Circle D, 3.73 posi 12 bolt, DynaTech f-swap headers, 3/4 drop, handling mods, etc. - my toy '72 Chevy LWB C-10 Highlander - 350/350 ps/pb/tilt/ac - not original but close '06 Chevy TrailBlazerSS - LS2/4L70e - little black hot rod SUV - my DD '18 Kia Sorento - wife's econo-driver '95 Chevy S10 - reg cab shortbed, LS, 4.3, auto... my '68's powertrain and chassis build -links broken A surprise phase - carb to efi -links broken |
02-18-2012, 06:32 PM | #23 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
Well here is my latest progress.
__________________
RCC |
02-18-2012, 07:56 PM | #24 |
Registered User
Join Date: Sep 2009
Location: ottawa,canada
Posts: 4,550
|
Re: LS376 / 480 With 4L80E
awesome!...I'm ordering me a set of those to try...they're $300 cheaper than the hookers and the quality looks good too..
__________________
my build threads '86 C10 http://67-72chevytrucks.com/vboard/s...d.php?t=415628 '67 C10 http://67-72chevytrucks.com/vboard/s...d.php?t=635078 '63 GMC http://67-72chevytrucks.com/vboard/s...d.php?t=674682 |
02-18-2012, 08:09 PM | #25 |
True Addiction
Join Date: Nov 2005
Location: FTL
Posts: 415
|
Re: LS376 / 480 With 4L80E
Great quality. I'm very happy with the fit as well.
__________________
RCC |
Bookmarks |
|
|