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LTX and LSXPutting LT1s, LS1s, and their variants into Third Gens is becoming more popular. This board is for those who are doing and have done the swaps so they can discuss all of their technical aspects including repairs, swap info, and performance upgrades.
I have a 305/700r4. the motor is running okay. I was planning a swap with an l98 but im not finding many that are good motors and a good deal. I am finding a lot of LT1 motors. I know the motor will fit and im not afraid of the wiring. what im worried about is the gauges. I read in an ls swapped 3rd gen that none of the gauges worked and he had to buy an expensive module to get it to work. if I go LT1 am I going to have issues with any of my secondary system?
ideally ,you want to get a donor car so you have EVERYTHING.several people have adapted the 4th gen dash entirely(it looks sick)
and if you find a t56 car (you can also use the rear,its about 1.5" wider)you will end up with an absolute potential beast.
lots of guys have turbo'd them and make insane power but even n/a it would be wicked and quicker than an L98 car.
so you have a plan,find a wrecked 4th gen 93 to 97 and go crazy.you will end up with a very fun car.dont just buy the engine....
when I get the motor I will get the complete harness and ecm but I don't want to change the gauge cluster. if there isn't a way to make it work I will stick with an l98.
when I get the motor I will get the complete harness and ecm but I don't want to change the gauge cluster. if there isn't a way to make it work I will stick with an l98.
Many folks have done this and getting the gages to work is very doable and straightforward. Spend some time reading the stickies above. Read and read and read. Soon you will see what you need to do.
the swap can be done with just the lt1 long block you redrill and tap the lt1 heads for sbc intake you dont need all the holes as only air goes through it theres no coolant that runs through the intake on gen 2
stick the dizzy in the back and reuse all your old tpi sensors, intake, ect you'll need a 350 prom though i have ran a few with stock prom and they ran and idled well
once the heads take a sbc intake the lt1 is basically a sbc with reverse cool you need the 4th gen belt accessory's and you have to mod the p/s with parts from a caprice to fit a 3rd gen since a 3rd gen uses a steering box forum on that is somewhere here on 3rd gen
the swap can be done with just the lt1 long block you redrill and tap the lt1 heads for sbc intake you dont need all the holes as only air goes through it theres no coolant that runs through the intake on gen 2
stick the dizzy in the back and reuse all your old tpi sensors, intake, ect you'll need a 350 prom though i have ran a few with stock prom and they ran and idled well
once the heads take a sbc intake the lt1 is basically a sbc with reverse cool you need the 4th gen belt accessory's and you have to mod the p/s with parts from a caprice to fit a 3rd gen since a 3rd gen uses a steering box forum on that is somewhere here on 3rd gen
Sounds like a lot of work, for little gain, to me. My 2 cents worth.
Many folks have done this and getting the gages to work is very doable and straightforward. Spend some time reading the stickies above. Read and read and read. Soon you will see what you need to do.
ive been reading the stickies but I haven't come across anything about the gauges yet.
the swap can be done with just the lt1 long block you redrill and tap the lt1 heads for sbc intake you dont need all the holes as only air goes through it theres no coolant that runs through the intake on gen 2
stick the dizzy in the back and reuse all your old tpi sensors, intake, ect you'll need a 350 prom though i have ran a few with stock prom and they ran and idled well
once the heads take a sbc intake the lt1 is basically a sbc with reverse cool you need the 4th gen belt accessory's and you have to mod the p/s with parts from a caprice to fit a 3rd gen since a 3rd gen uses a steering box forum on that is somewhere here on 3rd gen
that's a lot of work. that' sounds more like a conversion than a swap. im a planner. im going to get the motor, harness, and all needed parts so im able to do the complete swap in 7 days. I refuse to be one of these swaps I see that take months or years. if that means I get less power than I could get with a full ls swap than so be it. honestly im not against pepping up my 305. its a driver. I want it to feel fast and powerful but it doesn't really need to be.
Hold out for a 350. You can find them these days because lots of people are going LS. A straight forward swap is so much easier and a L31 or L98 makes plenty power in these cars.
The Lt1 will use the same oil and temp sensors for the gauges and the tach connects to ignition coil.The only issue I had with gauges is the speedometer,since the camro's have a speedometer cable and my T56 is electric.
I love my Lt1 and it runs great,I know the opti has a bad reputation but my cheap ebay opti has been going for nearly three years.
that's a lot of work. that' sounds more like a conversion than a swap. im a planner. im going to get the motor, harness, and all needed parts so im able to do the complete swap in 7 days. I refuse to be one of these swaps I see that take months or years. if that means I get less power than I could get with a full ls swap than so be it. honestly im not against pepping up my 305. its a driver. I want it to feel fast and powerful but it doesn't really need to be.
drilling and tapping a few holes on aluminum heads is alot of work? it took me 2 hrs as for the p/s even if you do a full swap with harness this needs to be done to have p/s its just a p/s line from a caprice that you can buy at autozone you also need at least the one lower radiator hose
i think its more work to get it to work using the 4th gen harness and gauges ect aswell as more money now you have to find the engine with a unmolested wiring ecu and cluster instead of just a lt1 long block i see lt1 long blocks used from 500-1000 bucks all the time and blueprint still sells replacement lt1 long blocks for $2900 with a 2.5 yrs 50k warranty
imo gen2 lt1s are the best bang for the buck you get 10.5:1 compression, aluminum heads, reverse flow and it accepts the gen1 sbc exhaust motor mounts ect. in stock form with intake and full exhaust they make 340hp throw a cam rockers some head work your pushing over 400hp
idk what you car currently is but if it doesnt have a tpi then it might be practical to do the full swap as you dont have the correct wiring, prom or knock sensor, your also going to need to take the gas tank down and get a tpi fuel pump tbis if i recall only pump to 15psi
I had a similar problem w/ an ATK reman LT1 long block. Was using coolant w/ NO visible leaks. "Dye Test" for combustion products in the cooling system was Positive. ATK wanted further testing done, for which they would only pay $50 per hour, IF an ATK supplied part was found (by ATK) to be defective. ATK wanted the heads sent back to them , at my expense. Labor in cali is $150 hour, not $50. I could buy heads for the price of shipping.
no remans for this guy,that's why ive got 2 350's and 2 305s.(and 4-5 of everything like water pumps,distributors)
one goes bad another goes in and i fix the other one.i snap up used and cheap stuff constantly.
i will eventually get rid of the 305's,they just seem to work well without drama.i like my car to be usable.
i just bought a 1988 GTA for $900,sold a few parts for $400 on the weekend so now ive got a set of gta rims,
an l98 350 plus tpi,plus built 700 r4,plus 3:27 posi 9 bolt disc brake rear,aluminum driveshaft,dual electric fans and rad,all air
conditioning parts, plus wiring + ecm and gauges,plus mint grey seats,full stereo plus swaybars etc etc.
oh,and a fiberglass hawks wrap around wing WOO HOO.....thats going on.oh,new window sweeps too!!
for $500...............wow,im gonna just buy cars and part them out from now on
will an L31 vortec swap like an L98 (TPI ),YES,THEY ARE VERY SIMILAR OTHER THAN
THE INTAKE MANIFOLD BOLT PATTERN AND PORT PLACEMENT.sorry bout caps,stupid keyboard...
that looks sick,makes me want to struggle and fight with efi instead of going the easy route
with all the carb stuff i already have.wiring ,multiple sensors,high pressure fuel system and
tuning frighten me
If all your worried about is getting gauges to work doing an ls1 swap..thats only a couple wires and a few changes in the tune to make it all work like factory. You don't need a module for that at all. All my gauges work in my original dash. Voltage is built into the original power wires going to the starter, fuel level I didn't swap gas tanks so no change there(just switched to a better fuel pump), coolant temp I used a 98 camaro coolant temp sensor that has 3 wires(1 for your original gauge,1 ground,1signal to ecu), oil pressure wired directly to the ls1 oil pressure sensor, tach signal had to be changed in the tune for a aftermarket v8 signal and then I wired that to the tach wire in the dash, speedo was also tuned for the correct gearing and then wired direct to the gauge. No module..just time,all of which I found by reading the stickies here
plus :
a) vortec L31 long block
b) edlebrock rpm vortec /holley intake
c) holley 650 utlra dp mech. sec.
d) moroso 1" carb spacer
e) hooker 2460 ceramic coated headers
f) old school vacuum adv. hei
equals: minus the aluminum heads,already have the serpentine brackets and pulleys
I have a LS1/T56 in my firebird all factory gauges, all AC, all heater functions 100% I have no converter boxes its all about the right sensors.
Temp sensor get the 3 wire 98 sensor, one lead goes to the PCM other to the gauge, it will be as accurate as factory gauges ever were (its slightly off but close enough)
Tach, you just need to do a pick up resistor to bring the 5vdc from the PCM to closer to 12v to drive the tach, then use hp tuners or other to change the tach out puts (factory its set up for a v6 tach)
fuel gauge doesn't change unless you run a LS1 tank, but there are solutions for that.
voltage will just work
oil pressure sensor on a factory 4th gen doesn't actually feed to the PCM so you can just replace the sensor from one on a 89 firebird it will thread in and feed the gauge right, or you can get an adapter plate that goes beside the oil filter.
check engine light wire directly to the PCM
Don't let the gauges scare you if you are comfortable with wiring, there is more support for the LSx swaps at this point than the LT1.
Now if you have an older one with a manual speedometer then you will either have to switch out the gauge or buy a converter box.
