kaotic_ws6

im doing a ls1/th400. i have the dished flexplate so im gettin the hughes spacer so i can use stock bolts right?

jay_lt4

iTrader: (4)

what converter bolt pattern do you have,, if it has the th350 and th400 bolt pattern you can just oval out the holes slightly on the ls1 flex plate and use the th350 pattern on the converter,,

if your converter only has the large th400 pattern you will need to drill the flex plate for the bolts

i have done both ways without any issues

otherwise if you get a flat flexplate and gm spacer from a lq4 engine with a 4l80e trans it will have the correct spacing and the th400 bolt pattern on it already,, just bolt on and go!

kaotic_ws6

ok cool, thanks alot for the info

kaotic_ws6

ok so im ordering right now, so i DO NOT need longer bolts correct? i dont know how i wouldnt but i dont much understand this crap and im gonna take your word for it if thats what you said. i just dont want to be behind on my order im in a HURRY

1981TA

iTrader: (7)

Let me add my $0.02

I'm working with a TH350 which supposedly came from an early 70s or late 60s vehicle. I saw the 71 El Camino it came out of, but traced the 350 SB it was attached to to a 69 Camaro. My engine is an LS1 from a 2001 base Corvette. I started out with a curved 5.3-style flexplate, the GM spacer, and the longer GM bolts.

Following advice here at LS1Tech, I mounted the flexplate first, then the spacer. This way, the flexplate lines up perfectly with the starter. The starter engages and does its thing. However, when I try to mate the trans to the engine, it gets to about 1/8 apart before the torque converter bottoms out in the spacer. I can tighten the trans-to-engine bolts further, but the converter then binds so badly, it won't turn. The converter IS properly inserted in the transmission.

Reversing the position of the spacer and flexplate, the teeth strike either the nose tip of the starter, or the face of the starter. However, the trans mates fine to the engine. From this, I'm reasonably sure a curved flexplate is a no-go for a LS1 to TH350 connection.

So, I ordered GM# 12621399 from GMPartsDirect.com. The delivered price to Indiana was $57. I believe it includes another set of bolts and a spacer, which I will not need. If anyone is interested, drop me a PM and we can work something out. At any rate, I will post again when the new flexplate arrives.

jay_lt4

iTrader: (4)

depending on the th350 converter snout some have to mill off about an 1/8 " from the gm spacer when you use it on the rear of the flexplate,, some converters work fine

the hughes spacer is only about $45 and works perfect with the curved flexplate

1981TA

iTrader: (7)

Yes, 1/8 appears to be about right. My milling skills (and tools) aren't so hot, and I already had the GM spacer/bolts, so I went with the new flat flexplate. I figure even if I sold the extra spacer and bolts for $30, I'm ahead. BTW, I'll also have a curved flexplate on the block, too Got it used off ebay for $20, and rat-tailed the holes to take a TH350. It would make a dandy conversation piece or decorative wall hanging.

slravene

OK, I'm building a swap now for my rock buggy...

Currently running a circa 1997 4.3 and 4L60E (with the removable bellhousing).

I am swapping to a 5.3 (early 200x year).

I want to keep my V6 Transmission as it has already had some work done to it. I have a 5.3 bellhousing that I can use that came off of a buddies 5.3 4L60E.

Will these bolt up without any kind of spacer/flexplate/input shaft/TC changes? I have come across so many different answers its almost silly...

5LTRETR97

iTrader: (2)

Thats probably why my bottom half of the bellhousing will not fit around the torque converter.

skeeter99

iTrader: (16)

great info!!

waxenate

iTrader: (5)

Thank you thank you thank you!!!! I love this website! I'm putting an ls1 (from a manual 200 z) into a 95 Z with the 4l60e. This will be my first instal ever so any tips or tricks would be greatly appreciated! thanks again!

96TransAmboosted

iTrader: (8)

subscribe

operatorfailure

iTrader: (3)

Alright, I seem to have found everything I need to hook my 6.0 up to my cars existing TH350 except the downshift/ TV cables. I have searched every post I can think of and no info except one guy said he got a kit from pace performance, but I can't find anything on their site about it. Everyone that has done this swap what have you done for a downshift/ TV cable?

codismaximus101

thanks jay your the man! im puting a 5.3 with a 700r4 into a 90's pickup frame with a 52 chevy suburban on top. and have gone around and around with different companies telling me i need this and i need that.. thanks again

waxenate

iTrader: (5)

Question...i ahve a LS1 Curved flex plate from a 2000 LS1. Which spacer do I need? BTW its going into a 95 Z-28 with the Lt 4l60e

jay_lt4

iTrader: (4)

the hughes spacer will work for you,, you will need to oval out the tc holes in the flex plate just a little to match the tc bolt pattern

jay_lt4

iTrader: (4)

ls engine / trans tv cables:

http://www.bowtieoverdrives.com/cata...php?ITEMID=225

http://www.tvmadeez.com/ls1_cam/

Trevor F

iTrader: (13)

how do you tell which flexplate you have?

mines part number
12580709 should have been from a 5.3

GNCLONE

I'm resurrecting this thread


I have a 6.0 with a stock flexplate, wouldn't putting a spacer between the crank and flexplate screw up the starter engagement?

jay_lt4

iTrader: (4)

nope,, not if you have a flat flex plate, you will be fine,, that is the way many 6.0L engines come right from the factory,,