Hey guys I got a chance to pick up a 1973 350 out of a police car for 50 bucks off a friend. Can I put a 305 tpi setup on it? Is there anything other than the fact that it was a police engine and probably beat on on occasion i should know about.

 

being from 1973 i dont think it will have much. is this a rebuilt motor. are you rebuilding it. 70s were an emissions era so i dont see much stock power coming from that motor. a decent rebuild and a some heads to match that tpi and you will be ok.

 

If your car has center vavle cover hold downs your intake and heads will not line up right. If perimmiter hold down bolt, think a '86 is, your tpi in theory will bolt right up.

problem 2: The heads may have different holes for brackets than an '86. Maybe none. That would be a pain with air and emissions.

'73 was lower compression but no cats so I bet it came with more HP stock than the '86. Good core to start with. The 350 with the same hp will have more toqure. I would do a lot of resurch on a computer friendly mild cam. The '73 cam and your 305 cam would both be wrong.



****if you get to much hp you will need larger fuel injectors to feed the engine.

 

why do you wanna do TPI??

might as well just keep it carbed. itll be faster with a 4bbl or two than it will with a TPI setup.

 

I think the only way thats happening is with some mods if I keep it carbed. If I could just slap my tpi setup on it and have a 350 tpi it would have alot more low end then a carbed 350. I think. lol.

 

Get a 350 chip and 22#hr injectors and you should be good to go.

 

Are you sure? That's pretty much all I would need? That year of 250 will bolt up with my 700r4 if I still use it right?

 

your 700r4 should just bolt up. its your standard sbc.

 

The 700r4 will bolt up to motor. You should get a custom chip to make it run perfect. More than likely the cam in the motor isnt close to the l98 cam so it probably run but not perfect. I had mine dynoed tuned at big shot dyno by www.lsracingchips.com . You might also need the 350 knock sensor but I dont think its necessary because im using a 305 knock sensor in my 406

 

Get the casting numbers and go to www.mortec.com and check them against the listings there. Chances are that it has garbage heads, and dished pistons. It would probably bolt up to your 700R4 but won't have any more power then your existing 305. Also keep in mind that the dipstick is on the wrong side of the engine. The only way to make it work is to use headers, the stock manifolds won't clear the early chevy dipstick. You might be able to use a 305 oil pan with the dipstick in the pan and plug the hole in the block also, but you'd have to investigate that option a bit deeper.

Another thing you'll run into is that the flywheel might be too large, your 86 has a 153 tooth flywheel. If the 350 has a 168 tooth you'll need the matching starter also and the inspection cover on the transmission won't fit.

With the donor engine being a 73 I'm assuming you're going to rebuild it. Check with a machine shop first, even if you do the bare minimum recommended work you'll have $900 in machining that engine. Another couple hundred in gaskets and 'while we're at it' stuff like waterpump, starter, plugs, filter, oil, sensors that will be broken, etc.

On the other hand, you can go to your machine shop and they'll probably already have a 87-up 350 core on the shelf that's been magnafluxed and inspected that they'll sell you and that they can build to your specs. Or else you could probably find a used L98 and rebuild it. You wouldn't have a dipstick issue, and you could reuse your starter and flywheel, and exhaust... Cost would be about the same at the end, since either way you'll need all the same parts...

I put a 76 350 into an LB9 86 T/A and I really wish I'd just built a 1pc RMS 350 instead. The $50-100 I saved on the core wasn't worth all the garbage I had to replace.

 

I've got an early TPI intake here that'll work for you, BTW. I'll sell it cheap as I've moved out of TPI. It's just the base and possibly the plenum, but I have no runners.