I been around the web searching about the Lt1 swap, and about turbo'ing a 305. I think I like the turbo idea better cause it seems to be cheaper then buying a Lt1, and it seems members here on thirdgen are making plenty of power with a turbo set up. I've been searching for a while and I think I understand know what is needed for this, but I just wanted someone to check to see if what I got from the other post is correct. Here's what I got so far. O yeah heres what I'm working with. 1989 Camaro RS 305 TBI

*Convert to TPI (not sure if you can turbo a TBI)
*New heads (vortec or pre 350tpi) to lower compression to turbo friendly range.
*oil pump doesn't have to be replaced if running low boost
*Old oil pump is fine for now, but upgrading would be a good idea
*Something about the O2 sensor (could someone explain this)
*For a twin turbo set up the saab and volvo tb03 turbos work well, as do chrysler tb03's, but they use bolt connecters
*And another issue about ignition (could this also be explained

If I get this done I would like to do a single turbo set up. I didn't find much about the single set as I did the double. Would a single turbo work well on a 305 or is it pointless? Anything info would be appreciated. Also if you start to talk about compression ratio's. boost, and equations, keep the numbers to a minimum or your guaranteed to loose me. Thanx

 

well the point of converting to TPI is so you can use the 749 ecm (from syclone/typhoon) which can sense boost and add fuel accordingly, you do have to reprogram the ecm, and doing it yourself can get very complicated, and paying someone could cost several hundred so take that into consideration, i dont know how much the 350 heads will drop compression, but as long as you keep boost down you should be fine, and it'd be a good idea to replace oil pump just so its reliable, and since you'll have the pan off anyways (to tap hole for oil lines), as far as the O2 sensor goes they are talking about a wideband, and that so you can correctly tune it, but again on a mild street motor you dont NEED it, as far as single turbos they can work very well, but you need a bigger turbo, some diesel turbos will work good or www.ls1motorsports.com sells a t-52 for $650, that would be a very good turbo for your setup IMO, when it comes to ignition aside from your basic upgrades, and going 1-2 steps colder on the heat range of the spark plug, i dont know what is involved with that

whether you go single or twin either you'd better be atleast an ok welder, or be prepared to drop some $$$ on the exhaust piping setup, also something to consider is an intercooler setup, i personally would say if you use OEM turbo's use the OEM intercooler aswell, but piping and location becomes an issue

 

thanx steve. im gonna do some more searchin, but it seems that not having to get a new engine is pretty much unavoidabe. i'm starting to lean back towards the lt1 swap, but i'm not exactly sure. any other info would still be appreciated.

ray d.

 

You can run a TBI off of a 749 and work with boost…

As far as expense, I don't see many people building a turbo setup for less then an LT1 swap. Hell, I snagged a dirty, nasty, needing new main bearings '95 LT1 (almost complete, missing accessories) for $100, and even if I did a complete rebuild I could go slightly better then stock with the parts and machine work for under $1K. Otherwise it bolts in… no fabrication…

OTOH, a blown 305 has more power potential then an NA LT1.

 

i've done some more research, and i'm pretty sure i'm gonna go head with the lt1 cause its simpler. since im young i don't wanna do something to complex...yet.

 

Well i have a 305 tpi and im only 17 and im buying two turbos from ford diseals and its not gonna cost me that much because my friend owns an exhaust shop so it wont end up costing that much besides the reprogramming. so i say go with the turbo not the lt1 and if u did decided to go with a new engine go with a LS1 i just found one 01 LS1 with T-56 with all the accs for 4900.

 

You can swap your MAP to a 2-BAR MAP from a syclone/typhoon and keep your TBI and stock computer.

It is easy to modify the TBI for boost. You can change the injectors to 90# 454 injectors. Air-flow is not a problem with boost. You need an extra fuel pump on the fuel feed to get better fuel pressure and flow. (keep the stock fuel pump in the tank as a feed pump)

The rest is fuel and spark tuning.

 

I actually did turbo a 305. It never quiet ran right because of an exhaust leak and it seemed to be causing false knock. It was really fast until it knocked and then it hit a wall. But it was really run and I drove it over 8,000 miles during the summer. I am now going to run the 749 Sy/Ty ECU and bin and get it running all right.

Deffinately worth it Deffinately a lot more of a WOW factor then a LT1.

 

I've actually gone back to the idea of turbo'n a 305 cause i was able to get a 305tpi complete engine for 300. i'm gonna do a compression and cylinder leakage test tomorrow. and the good news is my auto tech teachers thinks the engine may be a 350. im gonna go back to the junk yard and get the vin from the car. the dude that ran the junk yard didn't know much which means i may be able to pick up a cheap t-56

 

If you have the engine sitting there, why not just check the casting number on the block?

 

tell you the truth i didn't know there was a cast number on the block. ill check it when i go back to school.

 

I have a stock 305 tpi i'm thinking about puting a turbo what turbo would be a good idea? I'm thinking about putting an LT1 cam and diffrent heads i don't want anything big.

 

Turbo's are "easy" if you know what you are doing. Easy as in they dont take extreme knowledge to put together. But then on the other hand it is not easy to do all the fabbing. Piping can take forever to do, days after days. Relocating and trying to use orginal equipment can be very hard.

Turbo's are great, if you know what you are doing that is. Lots of people have never rebuilt any engine, never pulled a tranny or changed a rear out, but they put together a JYTT setup.

Do some more searching, if you are going with a FI setup here are some things to watch out for.


-Computer
Not quite sure on particular Application but can involved many things
-Fuel
Injectors
Pump
-Spark
Distributor
Coil
Other minor things
-Fabbing
Piping
Placement

This is just stuff off the top of my head. Each of these can require tons of your time. You can buy SBCs already in the 400+ range for around 3k or so. Spend another 500$ or so in supporting mods (fuel) and you have yourself a fun street car.