I've been curious to see some of these answers for a long time and hesitated to post because I was afraid it'd get deleted or something, but anyway...

The rules for the thread are... You have to own a 305 TPI engine, you have to be on your original engine, and you should post any engine work you've have done on it before.

This is all actually going to help me decide some major things I'll explain later. Thanks for any responses I get here.

 

117,000 on my engine.. I've only owned it for a week now so i havent done much

 

picked up my 305 tpi engine pontiac firebird formula ws6 about 6 weeks ago and it said on the odo: 199,000 but the odo is not working. Not sure if the engine was worked on or not. heck, still trying to figure out if it IS the original or someone dropped in a 350 engine in it. who knows.

 

bought it about a year ago and 86 tpi iroc z, god knows whats done to it, has alot of mods, 3 inch exhaust, auto shifter, headers, muffler, rims and tires, everything is different so i really dont know much about the engine

 

My bone stock LB9 took a crap at 117k.

 

My 1986 IROC-Z TPI 305 is probably the original. The odometer reads x14,xxx Miles, so I'm guessing 214,000 miles.

The car runs like crap, barely starts, barely stays running. I've owned it a week though and just started working on it.

 

car has just over 140,000miles bought it at 80,000 never had to touch anything internally. Replaced alternator, IAC valve. Been running a NOVI2000 (not the early ball type, this thing is a monster) for the last 5 years between 8-12lbs boost, has to be about 30,000 miles now, dont remember anymore. Current config in sig. Just barely starting to burn oil after all the torture new engine in progress

 

1985 TA 305TPI 156000 miles.

Work Done:
Headers and exhaust
Air Filter
New spark plugs and wires, didn’t need to, but figured might as well.
New MAF needed too, the old sensor died around 105,000 miles, easy change.
New rebuilt alternator, old one died, new one took 15 minutes to change and cost 80.00.

The computer is now tossing an EGR valve code once in a blue moon at sustained highway speeds so I probably should change it.

Even though I don’t need to, after this many miles I should change the fuel filter.

Other than that, it’s been a pretty reliable engine.
Oh.. one last thing, oil changes about once per year. I know and I should change it more often.

 

oh so mine has 140xxx i believe, it might be 240 cuz i cant tell but the engine runs damn strong for a 305

 

I bought my '86 with 57,000 on it. Re-did the top end, manifold, runners, and 56cc heads and the piston rings took a **** at 135,000

 

123K on mine. Bought it six years ago with 118K and immediately ran a new intake manifold gasket, tune-up stuff, corvette fan switch & 180 degree thermo. I'm pulling it out to do the rear main, oil pan gasket and new valve seals. While I'm at it, I'm sure it will get all new belts hoses and any necessary wiring updates. The engine still runs great, but I'm tired of the little leaks and puff of smoke. I may be lining up to sell it so I want it to be all sorted out.

 

OK... Mine has 113k miles on it and I was using this to get an idea of when I should start saving for a new engine. It runs very strong. Starts everytime and runs great. Thanks for the replies!

 

just pulled mine not too long ago.. 117k miles replacing with a 350 due to a lower end knock.. nothing spun just well worn bearings.. had about 17psi oil pressure at idle and a fairly loud knock.. it's rebuildable.. still havn't decided what I'm going to do with it.. its just a crappy 89 305..

 

As soon as financially possible, I'll be pulling my boat anchor of a 305 in favor of a 350. Ideally a stroked out 383. Never been much for the 305's myself, and with mine seemingly on it's last leg, I'm not changing my mind anytime soon.

 

My 305 appears to be well taken care of. I had a mechanic do an analysis and he says everything is working as it should be and is in great shape for its year. I think it's just a matter of how well it was taken care of.

 

137,000 on 86 TA 305 tpi LB9. just replaced with new hopped up 305, but was running fine, just alil smoke on startup.

still cant touch my 350tpi. nore the 383 HSR thats goin in

 

170,000 on stock 305. Last 5 years the car has only been used for a road race track day car.

car is run wide open for 20 min a time 5 times a track day. It has seen 6,500 rpms not by choice, but by wet track missed shifts, poorly excuted toe and heal technique etc.

I could not ask for a better engine.

4 alternators, 2 water pumps, 1 new distrubuter and thats all. Valve covers have never been off. Big radiator was needed for cooling and that it.

Car smokes on start up and runs very rich at idle, but no problems at WOT. I am going to keep driving it till it stops and then switch to an LSX.

 

Mine has 130,xxx full boltons including 125 shot of nitrous. Internally stock. Also stock transmission. replaced waterpump, and alternator. Everything else works great...so far...

 

1986 Camaro IROC Z. 305 Tuned Port. 700-R4, 3.23 axle
car has 223,583 on it and finally wont start after almost 5 years of ruthless beatings and burnouts.

Replaced Alternator, Radiator, Battery, EGR, Oil + Filter like 100 times, Installed 88 iroc serpentine setup. MAF, TPS, Coolant temp sensor, O2 Sensor, Tranny mount, transmission itself, and air temp sensor,

im about to finally pull the motor this fall and rebuild the factory 305 to better then new condition, and i can finally remove all the emissions accept for the cat.
and yes the car is staying a 305, im not looking for extreme performance, just a modest 5.0 with a mild cam and shorties

 

very good. Whatever comes along I will keep mine going. I take care of my engine. I actually haven't done a burnout in about 2 months because I bought new tires and I kinda wanna keep em fresh, but if my old tires don't sell soon... YOU KNOW WHATS GONNA HAPPEN! =]

 

I have 179,000 on mine, completely stock internals. It's had a couple bottles ran through it as well.

 

Very nice! Good to see the majority of these are pretty reliable.