i have a 1989 camaro that had a 305 tbi from the factory. last week i completed an engine swap. i started with a 350 jasper rebuild engine that had 30K miles on it. i tore the engine apart on my stand, took everything but the rotating assembly apart. installed all new gaskets, an edlebrock performer plus camshaft, a new timing chain, and all new gaskets. i bought the engine for 300 and invested another 400 in gaskets, cam and lifters, oil pan, double roller summit timing chain. total cost of engine was less than 800 bucks. im really pleased with the way it runs. it sounds more aggresive, and makes for a much better cruiser. driving around town only requires very light pedal pressure, which i love. i love a car that moves with little or no effort. i would also say that so far the gas mileage is about the same as the 305. anyone considering the 305/350 swap i highly recommend it. its well worth the work, and makes for a much more enjoyable car to drive. its like the engine was made for the car. i might think about buying a holley tbi unit soon. i think that would add a significant performance increase.

 

You have not performed any injector / ECM changes over 305 baseline?? From you engine description it sounds like a very nice combo - going to Holley Injection may not be the optimum route (money vs. performance gain). Unless done so already I would look into getting 350 injectors (62 lbs) as this will cure some AE and WOT issues. Tuning and driveability optimization would be close second on my list. Third on my list would be exhaust system to wake up your new 350 (and more tuning ).

Enjoy the ride!

//RF

 

the 350 that i bought INCLUDED the original 350 injectors. im not sure of the # rating, i dont know how to identify them. i do know that im not using 305 injectors, i understand that the larger engine requires different injectors, different PROM, different knock sensor, and a different ESC module. i bought a new ESC module and the engine still had its knock sensor and injectors. i bought a PROM from TBICHIPS off of ebay. what im looking for is a unit with a larger bore size. i hear of some people using a 454 injector housing, does that bolt right up or does it require adaptors? the engine runs great at wide open throttle(doesnt miss or hesitate) but my stepfather thinks this engine still has more to offer. im thinking of adding a holley tbi, and maybe a MSD igition. its still a huge improvement over the L03, which is a reliable engine but a dog.

 

Yes, stock TBI intake manifold is not an optimum for your 350. IIRC, stock LO3 intake manifold bores were machined to match 43mm bores of your SBC TB bores. BBC and holley are 51mm bores. I would ditch stock cast iron intake and go with a dual plane, fully heated aluminum intake. There are several options one should consider - carbed intake with TBI adapter or a dedicated TBI intake. This has been discussed in many threads - use search. I would also seriously consider exhaust work to bring out engine potential. Finally extracting full performance potential tuning and optimization is required - look into EBL (no more chips, on the fly tuning)

To ID TBI injector look at its top, 350 truck injectors have paint code red/black and were commonly available under #5235206 among other service numbers.

//RF

 

im not using the L03 manifold, but the manifold that came with the 350. i'm guessing they are the same. as far as the exhuast goes, it was replaced a long time ago. im running edlebrock TES headers, 3" catco catylic converter, and a 3" edlebrock exhuast. it sounds really mean with the 350, allot deaper than the 305.

 

What heads are you running? I'm pretty sure Edelbrock advertises that cam, along with their RPM heads and intake, to make over 400 hp. I doubt that Jasper rebuild came with very good heads (unless they were vortec), so they may be holding you back.

 

I am building a Vortec 350 for my 89 right now as well, i am just havbing a hard time finding the prom and injectors needed. There is a parts place here in Charlotte called Youngs F body parts that I am going to call and see if they have anything but I sure can't find it anywhere else. I have seen the proms on eBay but it says you have to tell him what setup you are running and well I have no idea what to tell him, i am going to be using all the parts listed in the budget build on this forum. I also want to ask if you exchanged the fuel pump when you did the swap, I just put a new fuel pump in mine about a month ago and was thinking I may need to go ahead and change it again to one that will pump more fuel to the 350

 

the fuel pumps are the same, at least between a 350 tbi and a 305 tbi in the same application. example would be a c/k series pick-up truck or a caprice, i cross referenced the part #'s on autozones web site and they are the same. im running the same fuel pump and have no issues that i can tell so far. i used the fuel injectors that came with the 350. the heads im using are the stock 350 tbi heads. i know that they probably arent the best flowing heads, but new heads cost $$$. my wife and i are buying a house soon(hopefully), so money is an issue and if it aint broke, i aint fixing it for now. i did run my car down the 1/8th mile and i got a whole 1+sec improvement over the 305, which is noteworthy. the 350 has allot more low end torque and at low speeds it has some punch. it seems to run out of steam at higher speeds. it is much better than the 305 though.

i did have one issue that i cannot understand. when the car is cold, before it goes into closed loop it runs somewhat poorly. it doesnt idle consistantly. when you drive it when its cold, if you get on it, it seems to have a slight misfire(not bad, just noticeable to a trained ear). i dont really know whats going on there. when the engine reaches operating temperature, it runs smooth with plenty of power and doesnt skip a beat. i drive it easy until its warmed up, no codes. not really sure whats going on there. really good news is that this engine gets really solid oil pressure, 30lbs at idle with a warm engine, 50-60lbs at throttle.

oh, yeah i also want to add that my car does not miss at all idle, it doesnt hold a steady idle. idle will wander up and down until engine has reached temperature