When space,money and time allows it i wanna swap my l03 car to carb, i want something simple and not too expensive, if it is possible i wanna try to get this motor to develop a healthy 280-300 HP ofc if its not too tired already to do this, my l03 has about 140k but i do oil changes every 3000 miles and i keep her really clean always , this motor runs like new i think it can handle some more horses. I want to do something similar to this https://www.thirdgen.org/forums/carb...bi-update.html, hes swap seemed very simple , all he had to do was pull out the original intake and slap a carb intake there with a new distributor and carb. I wanna leave my computer in the car, this is my dailydriver and only car and i just dont want to mess around with the vats system etc, plus i wanna keep my AC working fans ect ect ect, im going to leave everything conected.

My biggest worry is since i have a 700r4 is the torque converter lockup, all he did was install a toggle switch for it, now it seems like a simple solution but i would like something more automatic, since im leaving my computer connected to the engine just ofc not the injectors etc would this make the tc stop locking up ? I dont see why since its still going to be working like normal, if it is not is there some alternate ways of making my tc lock up on its own without having to press some switch on and off everytime i get and leave the freeway.

Also i was thinking of getting an lt1 camshaft and a pair of vortec heads(ofc i would mill them down to around 60cc to not lose compression) for the 305 and swap it along with the carb, u think this combo of parts would let my 305 breath and get to atleast the 300 HP mark, i have seen some articles were some guys took an old 305 motor and put vortec heads , a similar lift camshaft like the lt1 and a carb and they squeezed 375 HP out of it, if that 305 did it i think mine can also with similar parts, all i want is around 300HP to play with the car, i think a 350 would just be overkill for what im looking for and since the motor is already there hey why not, a 350 will maybe find its way in my car when the 305 takes a poop.

 

You'll need a fuel pressure regulator, too. Check the stick at the top of the board for TCC options.

 

yeah i know about the regulator , i need one with a return.

 

yes u do. as for the lock up. TCI makes this kit that you install in the tranny and its locks up automatically. thats what i put in my 700R4. works great!

 

I am not familiar with the 700r4 but...

A set of machined vortec heads with a minor port job milled, as well as a new cam, intake manifold, 600cfm carb, and headers. Should bring you up close to 300hp.

Aftermarket heads, after market cam and valve train will get you closer to the 375 mark. This are all figures at the crank though.

 

It's cool that you want to keep the computer hooked up, but I am thinking that you might have a problem with the o2 sensor. It might trigger the check engine light all the time. So like apeiron said read the sticky's there you should find a way around that. As for the cost I can doing a good setup for around 300.00. at hit the HP you want to get easy.

 

Im going to just remove the check engine bulb, i mean with some of the stuff disconnected its going to turn it on anyways.

 

Keeping the computer hooked up will do absolutely nothing on a TBI car - you might as well remove it. The TBI computer only serves the injectors and the timing, when you go carb there will be no injectors, and you have to change dist to a vac adv one anyway. There's no way to make the computer work the TC lockup, you will have to install a kit like the TCI. You can pull the plug on the computer and therefore you won't have any SES light. The fan will operate normally, but I recommend a seperate fan controller anyway where you can adjust the fan on temp down. And you'll have to do headers and exhaust if you want to see any of that engine work (cam, heads, etc.) make any gain.

 

i know i have to switch to a vac advance distributor, im going to leave it in cuz i just dont want to mess with the whole vats stuff. Also im worried if i take all my wiring out how would i take care of the AC for example, i see both cables that connect to the ac compressor they both come from the wire loom thats connected to the rest of the wiring relating to the ecm or are they a separate wires ? Also the fuel pump, but that could be solved by just removing the sending unit and placing a carb pickup instead with an inline pump, but would much rather leave the stock pump there and just use a return style regulator. I would like to know as much as possible before i start doing all this swap.

If i can get away with removing all the ecm related wiring while keeping my ac functional, stock fuel pump and not have to worry about the vats stuff then it would be better.

 

The VATS can be bypassed with a resistor inside the column. As for the AC that shoud be a seperate from the computer as well. The ECM has nothing to do with the AC compressor or blower motor as far as I can remember. I could be wrong maybe someone else here could say for sure.

 

I would personally pull the tank now, and build a carb pickup while the car is "down." much easier to do everything at once, than to have to fix shortcuts down the road. much more reliable too. I recommend the carter OEM replacement for the LG4. under 30 bucks. I would also recommend an inline low pressure regulator such as the holley or quick fuel unit. i will be getting one soon.

I am also installing a summit brand standalone electronic fan kit. 200* on/185* off. its even cheaper on ebay. 35 bucks.

For a carburetor I highly recommend something from the 4150 lineup. preferrably a double pumper. RPM dual plane intake to wrap things up.

...for the transmission I run the painless lockup kit. it automatically looks the TC when it shifts to 4th. it also has a vacuum switch that unlocks the TC when you stomp on it.

And of course don't forget you're going to need something to reset the geometry for the 700r4 tv cable. The associated holley brackets work OK, but the TVmadeEZ system from bowtie overdrives is where its at, and is well worth the money.

The "kickdown"/throttle valve cable is the tranny's only link to the outside world. Everything is controlled by it. Timing, pressures, shift points, etc.

Last thing you wanna do is fry the transmission or have to put up with it being temperamental. Been there, done that. Have the t-shirt.

150$>transmission rebuild. Ask me how I know?

As to the ac lines, pull the looms off and trace the wires.

 

Hey thanks for the advise, my car is still running , atm its my only DD so i cant be doing that, now what i want to do is get all the information i can get from here so i know once i get everything started it will go as planned.

Ill be going with a 600 cfm edelbrock carb and a dual plane manifold, ill prolly also get an lt1 camshaft or equivalent and a pair of vortec heads, drop it in and go from there, when money allows it and the car is running smooth with the conversion then a mild 350 will go in.

Also i was thinking of swaping to a t5.

 

If the fuel pump has never been replaced - might as well do the carb pickup as mentioned - it's easier to do the pressure reg since you don't have to drop the tank, but it's gonna happen sooner or later anyway - all it costs you is another day.

Everything will function as normal without the ECM - it has no bearig on A/C or guages or anything. Just seperate the A/C wires from that pass side bundle, and then you can tuck the entire unused pass side ECM harness in the fenderwell sight unseen to have access to at any point later.

There won't be anything to bypass with VATS really - just either 1) ground the starter enable relay or 2) remove the starter enable relay and run a short heavy guage jumper wire on the relay connector from the yellow wire to the green wire.

If I had plans for a 350 later, I'd skip the T5 - save up for a T56 - some do ok with a T5 if they are gentle, most kill the T5 with a 350 from what I read.

If you decide to use stock pump and reg, all you need to do is cut the green/white wire at the fuel pump relay and connect it to any hot-in-run - then the stock pump will run anytime key is ON.

 

Hey nice advise you see i didnt know any of that lol, if i remove the ecm ill just remove everything that has to do with it also, i dont want any unused cables.

 

Consider leaving the wiring in place, and just unplug the ECM. Reason why - 1) yo don't remove anything that you just might need, and 2) it tucks easily in the fenderwell sight unseen for use later. I've used my old wires for alot of mods, light exterior lights, under hood lights, TCC lockup, fog lights added, etc. It's been great having an almost unlimited supply of wires that run from inside to outside - I never have to run, drill, or route wires when I decide to add something extra - I just tap into an unused ECM wire - real handy!