"beej"
NAXJA Forum User
- Location
- Bonney Lake, WA
Noob to this forum, so flame if you must.
Just thought I would start a thread about swapping an LT1 into my '88 XJ
From hours upon hours of research I was unable to find anyone that had done this exact swap, so I figured I would share my info, plans and parts list, in case anyone else was considering a swap of this nature.
Start off with what I have and how I got it
LT1 from a '94 Buick Roadmaster, with the vented Opti-spark, also included harness and computer
( Got the running car for free, was paid $200 by the customer to remove parts that would work on his "new" roadmaster after "totaling" the old one. scraped the car, cat converter and aluminum wheels for $350", also sold the transmission for an additional $50)
700r4 and 231C HD (traded a rifle, that i paid $200, to a guy on craigslist for a 4.3/700r4/t-case. sold the 4.3 $100 and kept all the accessories for possible install on the LT1)
Free corvette servo for the tranny
homemade egr block off plates
modified water pump
Airfoil for t-body
3 pack of 11" electric fans
Things I'm planning on getting/using
Novak motor mounts (they seem to be much nicer than the AA ones, and offer adjustability)
ecm reflashed by lt1 swap.com (very reasonably priced, has good reviews on some of the f-body car sites, can remove VATS and all emissions, a/c and electronic trans controls)
exhaust: will be attempting to use the stock manifolds and then fabbing the rest up from scratch
will be attempting to use the stock fuel pump and fuel lines
Progress so far
Old engine removed
Harness stripped down in cherokee to remove all the old renix and trans controls
harness from lt1 stripped down and sorted out
basically just waiting for a few more dollars to purchase the motor mounts, motor is cleaned up and ready to go in.
Why am I doing this?
Old motor was very very tired
Tranny was no longer shifting properly
Because I basically got a running v8 for free??
looks like i will be gaining about 110hp, and maybe more considering how worn out the old 4.0 was
Yes I know that there are issues with the opti spark, but if you use common sense I really don't think it is as big a problem as people make it out to be. The opti has a new cap and rotor and has been silicone sealed it is also the vented kind which does alleviate a lot of the issues with moisture, how ever i will be taking other precautions to prevent water intrusion. Also after i get it up and running I'm going to work on a custom fabbed intake and distributor to rid the motor of the optispark, but still retain the current electronics and ecm
Current Specs
88 XJ
Mileage=an assload
front suspension= 7 inch custom front springs with rusty's high clearance long arm kit
rear= custom springs with a little block and a shackle
steering= homebuilt junk
cage= dirty home fabbed, but trail/rollever tested
I will add some pics later.............
couple older pics
Yes I know it's a p.o.s. and there are a lot of things on it that look horrible.................
Just thought I would start a thread about swapping an LT1 into my '88 XJ
From hours upon hours of research I was unable to find anyone that had done this exact swap, so I figured I would share my info, plans and parts list, in case anyone else was considering a swap of this nature.
Start off with what I have and how I got it
LT1 from a '94 Buick Roadmaster, with the vented Opti-spark, also included harness and computer
( Got the running car for free, was paid $200 by the customer to remove parts that would work on his "new" roadmaster after "totaling" the old one. scraped the car, cat converter and aluminum wheels for $350", also sold the transmission for an additional $50)
700r4 and 231C HD (traded a rifle, that i paid $200, to a guy on craigslist for a 4.3/700r4/t-case. sold the 4.3 $100 and kept all the accessories for possible install on the LT1)
Free corvette servo for the tranny
homemade egr block off plates
modified water pump
Airfoil for t-body
3 pack of 11" electric fans
Things I'm planning on getting/using
Novak motor mounts (they seem to be much nicer than the AA ones, and offer adjustability)
ecm reflashed by lt1 swap.com (very reasonably priced, has good reviews on some of the f-body car sites, can remove VATS and all emissions, a/c and electronic trans controls)
exhaust: will be attempting to use the stock manifolds and then fabbing the rest up from scratch
will be attempting to use the stock fuel pump and fuel lines
Progress so far
Old engine removed
Harness stripped down in cherokee to remove all the old renix and trans controls
harness from lt1 stripped down and sorted out
basically just waiting for a few more dollars to purchase the motor mounts, motor is cleaned up and ready to go in.
Why am I doing this?
Old motor was very very tired
Tranny was no longer shifting properly
Because I basically got a running v8 for free??
looks like i will be gaining about 110hp, and maybe more considering how worn out the old 4.0 was
Yes I know that there are issues with the opti spark, but if you use common sense I really don't think it is as big a problem as people make it out to be. The opti has a new cap and rotor and has been silicone sealed it is also the vented kind which does alleviate a lot of the issues with moisture, how ever i will be taking other precautions to prevent water intrusion. Also after i get it up and running I'm going to work on a custom fabbed intake and distributor to rid the motor of the optispark, but still retain the current electronics and ecm
Current Specs
88 XJ
Mileage=an assload
front suspension= 7 inch custom front springs with rusty's high clearance long arm kit
rear= custom springs with a little block and a shackle
steering= homebuilt junk
cage= dirty home fabbed, but trail/rollever tested
I will add some pics later.............
couple older pics


Yes I know it's a p.o.s. and there are a lot of things on it that look horrible.................
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