rodie_27

I recently found out my 305's block was cracked in my vert. Long story short, I plan on putting in a 350. I'm kinda new to it and need to know what will work. I'm planning on keeping my 305 heads to bump up compression (64cc's?). Can I reuse 19# injectors and also what about the ECM? How do I go about updating my computer? I want a fairly mean cam but still have power brakes. Not looking for crazy horsepower, just impressive. Thanks in advance

Kevin91Z

iTrader: (1)

This forum is FILLED with 305 to 350 swaps. Just read and

rodie_27

No, you're absolutely right, this site is an oasis of information. I searched through I think 6 pages of stuff but the most important thing I need to know is about my computer and injectors. I couldn't find any 100% specific threads, but I might be able to look tomorrow. What would be the best place to have my computer adjusted? Or could I simply swap it with a factory 350?

TheRealBlkBird

Keep the stock computer, swap out the PROM. Definately swap in 350 injectors.

Kevin91Z

iTrader: (1)

305 heads have 58cc chambers, but they flow so little they will choke any good camshaft you put in.

If this is a stock 350 you can use the 19lbs injectors and 305 chip. The computer is the same for both 305 and 350 TPI, but the chip is different. If you want to put on aftermarket heads and cam, you will need a custom chip burned, either yourself or find one online. Ask your fellow IL friends for a recommendation.

bob8703

hey i plan on doing the same thing. would i have to switch the wire harness too if i did the same setup. i pan on keeping the same tpi setup also.

TheRealBlkBird

You can but why? You said it yourself the chip is different, and why use the 305 injectors?

bob: as long as they're both MAF or both SD you dont need to mess with the wiring at all. And if you're re-using the TPI set-up that came on the car, there's nothing to worry about.

bob8703

well i plan on doing the same thing as rodie_27 because this is my daily driver and i do work full time. so i would use the same heads and injectors till i have a vacation and i can upgrade those at once. and i cant go extreme now because i am using my tax money to get the motor block. and maybe if the price is right i can find a motor and heads together and this i will do everything at once.

Kevin91Z

iTrader: (1)

A 350 is 13% larger than a 305, and 22 lbs injectors are 14% larger than 19 lbs injectors. The ratios are the same, and there is very little difference in the chips other than some TCC lockup values due to the different rear end gears in 305 automatics and 350 automatics. The fuel and spark values are within 5 points of each other across the board. No its not the optimum setup but it will work if its all you have.

rodie_27

Wow, great replies. I had intended to mill out my heads a bit once I took them off my motor. 305 heads will have lots of metal I can grind off to provide much better flow (Correct me if I'm wrong). My buddy did that; 58cc heads and rebuilt 350 with hot cam and a 670 cfm street avenger.
So I want to put in decked flat-top pistons, I think my car will like the higher compression (more power hopefully) and use a bigger cam with it. So Kevin, would my heads be such a bottleneck even if I mill them a bit? Remember, this is a budget project, but still let me know how far off-base I am

Kevin91Z

iTrader: (1)

Yes, 305 heads are a bottleneck, no matter what you do to them. They're the second reason why building a 305 engine isnt worthwhile. (the first being the 305's small bore size). You should be able to find a set of stock iron L98 350 heads for sale on this board. Part #14101083. Even those stockers are better than stock 305 heads. A set of Manley 22410-16 springs, Manley 23652-16 retainers, and Manley 42106-16 3/8" screw-in studs, and you're in business for any camshaft up to .550" lift.

TheRealBlkBird

To me you're just making the case to do the swap. Sure it will work if that's all you have but that's not a very good reason, doing things half *** just leaves you with a half *** car. Please, swap the injectors and chip. BTW, Im not just trying to argue here, I already have one moderator who does'nt like me and has to follow up all my post with some kind of remark so please dont take it that way. I just want rodie to get the most out of his swap and not have any regrets when its not performing up to par.

ljnowell

What the OP is saying though, is if he just swaps the block and whatnot, will it run OK. He is implying he wont have the capital to get injectors, chipwork, etc. If thats the case, go ahead and run it, why not? When you get the money, do the rest.

My 2 cents: Dont try to run a big cam with TPI. Until you get it tuned, you will be lucky if it runs. Second, 305 heads are not really a bottleneck if ported. If you have the money get bigger valves installed, and do some home porting, the 305 heads are good budget performance heads. Just dont spend too much money on them.

TheRealBlkBird

Yeah, I know what he's saying, yet here he is talking about having expensive, needless headwork done and he wants to keep the 305 chip and injectors because he dont have money? He's talking about all this headwork and bigger cams because he wants the most hp out of the motor. He NEEDS to swap the chip and the injectors before he starts worrying about cams and hop up parts.

87tpi350,6spd

iTrader: (12)

Well I can tell you 305 injectors work just fine if you buy an adjusable fuel pressure regulater to bump up the fuel presure. I ran my tpi 350 with 305 heads like this for a couple of years with no issues.

ibmtech

iTrader: (1)

I see this all the time. At 1st he wants to do an engine swap from a 305 to a 350 but on the other hand he talks about putting in an aggressive cam, flat top pistons and porting the heads. If someone is going all that way to change cam and possible pistons. Why would you want to use 58cc heads even ported out unless it is a $$$ issue?? .. Isn't that like using a 4340 crank, JE pistons and stock rods???

If the engine is using a MAF ecm I believe the part is 1227165 then, I would consider repinning the ecm to a 1227730 Speed Density only if you are doing major mods to the engine, otherwise stay with the MAF system. If it is already speed density leave it alone.

If you upping the CC's, You might consider swapping to the larger injectors. You will have to have someone reprogram your ecm to give it the fuel and spark that it requires though. Or you can bandaide your system and get an adjustable fuel pressure regulator and leave the 19's and adjust from there.

So many people do a quick fix now, then later find out that might not have been the best choice in the future, then spend more money to get it done right the second time. Been there and done that 1000's of times.

87tpi350,6spd

iTrader: (12)

Yes I forgot to mention it was with a very mild cam. If you are going for a high performance 350 than just buy the good stuff. But that gets really expensive really quick. Since if you want a large cam yopu have to upgrad almost everything to complement it.

rodie_27

I talked to the local machine shop yesterday and first thing is I need to pull my heads off. Can't do today, it's raining. Assuming they're 58cc's, I'd like to do (pretty much what LJ said) some home porting and maybe go bigger valves. I want to run decked flat-top pistons (putting me a hair under 10:1 compression) and a mid to moderate C cam. <== (Need input/advice here)
So what I need is this; How much will it cost to upgrade my injectors? How much will it cost to update my chip? If my stock 305 TPI was putting 220-230 flywhell HP, Should I notice an appreciable gain?
I also want to reiterate, I am on a budget and I'm not trying to go insane on power. That being said, I want it to be a fast and fun vert, but also an everyday driver. Maybe that's not reasonable, I'm just not all that familiar with the TPI yet and want all the input I can get, even if you have to set my ways straight.

five7kid

iTrader: (14)

Something tells me you're misusing the word "decked" here.

Kevin91Z

iTrader: (1)

I understand what you are saying and there are no hard feelings. I agree with you, its best to do it right the first time. But not everyone wants to listen. They all want to reinvent the wheel doing it their way.

ibmtech

iTrader: (1)

This is another mistake made by alot of people. I know there are some companies out there that claim if you send them all your needs and details of your engine, they will burn a prom for you for $200 - $$$.. They might get you within the ball park, but you will most likely never hit a home run with these aftermarket chips.

Once you start talking about doing mods to your car, The next option should be starting to learn to use the programs and tools necessary for getting the most power from your particular setup.. You can build the best engine in the world, and if your prom isn't setup properly, You might as well never upgraded it.

www.moates.net is a good place to start and start doing research from DIY-Prom forum's on thirdgen.org. There is a plethura of information on what to look for and what to do.

rodie_27

Ok, well I got my heads, intake, etc. into the shop to get worked over. In the meantime, I need to figure out what I want to do about a cam. I have the stock 350 hydraulic roller cam they put in the 305's with a 5 speed. I'm doing a mostly stock swap to a 350. Does 10:1 compression ratio work well with TPI? I really need to know though, what kind of duration, lobe separation, and lift am I looking for? Basically, should I keep my existing cam or buy a new flat tappet?

ibmtech

iTrader: (1)

If you are getting your heads and intake reworked.. Why would you want to stick with the stock cam? Since you already have your block tore down that far. Go the rest of the way and get a better cam put in.

TPI's uses a Hydraulic Roller cam not a flat tappet.

theredman76

There is a few other options as well ecklers has a set of heads on there for a 305 that are 1.94/1.60 heads that would work well on there and are a lower profile set to fit under the hood of your camaro and are a good price as well too? might check that out and think about it!!!!

http://www.ecklerscamaro.com

DukeofHurl

It sounds to me that he wants to get his 350 swap up and running without dropping alot of cash. A few upgrades along the way might be ok if he can afford them at the moment that he has to plop down the cash. But for the most part I think he just wants to get the 350 running solid so he can build on it from there as money allows. If he does all the "might as wells" first he might not be able to drive his car for a year. So will his 350 run with a 305TPI setup? Sorry if I'm being blunt.

bob8703

like i said above, im in the same boat as he is. i just live 5 miles from work so im like the OP i just want to get it in and running and work on it slowly from there. all it needs to do is get me from point A to point B and when the next vacation comes around ill be doing the major stuff. so i understand where the OP is coming from.

bob8703

Hey rodie_27 tell me how it goes when you are finished. that is if it gets done before mine