cmwatcds

Attachment 321612





I hope this is the right place to post this and I apologize if it is not. I am certain this question has been asked many times. I apologize for asking again but I couldn't find this specific question.

I have a 1991 1 ton chevy pickup with a 350 TBI engine and a 4l80e trany.

I am swapping the 350 TBI for a 2003 5.3l engine. I threw the rod through the oil pan and this is the engine I have.

I had purchased the Speartech wiring harness, the engine relocation kit and the spacer for the 4l80e conversion.

So here is the problem that I am having, I posted some pictures to assist in this question. The flex plate that came with the original engine is a 6 bolt hole flex plate to connect with the heavy duty torque converter. I want to keep the heavy duty torque converter since it is a truck. The original flex plate is the same diameter and the bolt holes align, well except two as to which you can see in the pictures "hopefully". so can i just drill the two holes in the original flex plate and use the spacer to offset the flex plate from the engine? or what is the suggestion here. I really don't want to buy a new torque converter unless there is no other reasonable choice.



Thank you for all the help.

Chris

Pocket

iTrader: (22)

If the two flexplates are the same diameter use the old SBC one. If not, get one from a 4L80E LSx. Easy to find for <$50

futureuser

iTrader: (1)

I can't answer your questions, but I can offer a potential solution. Many folks like me have replaced our stock 4L80e converters with aftermarket ones. For examble I have a 2009 low mile donor driveline in my signature swap and went with an aftermarket converter. If I was offered enough money to pay shipping and my time to ship the stock converter, I would. In other words stock converters can be had cheap, even recent ones.

G-Body

iTrader: (4)

Is the flexplate from the 5.3L flat or dished? You don`t need to buy a new convertor, at worst you need a 4l80e LS flexplate (its flat and should have the 6 holes already drilled in it) and the spacer.

Bo185

If that's the 5.3L flex plate it will work. Just drill the holes as needed. The spacer actuall goes on after the flexplate for the dished 5.3L flexplates. The flat flexplate it will go on first then the flex plate.

The flex plate pictured on the right looks like a flat 6.0L flex plate but the holes should line right up. But hard to tell.

cmwatcds

the 5.3l flexplate is dished, I can buy a new torque converter but im not really certain which one to buy to be equal to the heavy duty one I already have.

I will check into the LS flexplate. I assume I can get that from summit or jegs?

in the pic that has both plates in it the one onthe left is the 5.3l dished flexplate and the one on the right is the 350 tbi flexplate.
the problem I encountered with putting the 350 tbi flexplate first and then the spacer is that it is to close to the block. the tbi flex plate is just a little bit thicker than the ls flexplate. just my luck its just enough to rub the block. plus it has a big weight on it. To me it sounds that I am probably better off with getting the other flexplate.

I am still open for ideas as well. thanks a million I am so ready to get this project done. I miss my truck, lol

thanks for all the answers so far

Chris

cmwatcds

everywhere I looked it was 200 for the flex plate and 400 for the torque converter so anymore suggestions.

71403

https://ls1tech.com/forums/automatic...0r4-4l60e.html

6.0/4l80e flexplates are $30-$50 all day long on greedBay, usually come with the spacer too.

If you can find a yard that has one on a motor grab the longer bolts with it instead of GM at $5/ea.

cmwatcds

I found this one from summit for 65 but I'm not sure if its the right one.

ATP 135-Z270 - ATP Flexplates

http://www.summitracing.com/parts/ATP-Z270/

71403

By the applications listed that looks like the right one 4.8/6.0 4l80e

cmwatcds

I bought this one so we will see how it goes.

the other reason I wanted to stick with stock is I dont want to go thru a thousand starters trying to find one to fit. so I am really hoping all this works. Thanks again for all the help

Chris

cmwatcds

well thank you to all the comments. the flex plate kit I got worked perfect. now I just hope everything else works OK. lol.