TBI 350 to C 383 Swap

[565bbchevy]

The least expensive way would be just swap the 350 into your Cutlass and covert to a carb set up like you wanted to. If you have the budget for some good heads and new cam that will be a decent increase in power.
Most of the expense of converting a 350 to a 383 is the rotating assembly and the machine work involved in prepping and reassembling the short block.
And as stated not knowing your budget, if you are paying for a shop to do the engine assembly and install then that is going to eat up a big portion of your money.

 

[xylorex]

I did a tbi 350 to mpfi 383 on my 1987 k10 (v10 really). I'm really happy with it, glad I went fuel injection. The trucks with factory tbi make it much easier because the fuel tank & lines are already there.

I was able to convert from flat tappet lifters to roller lifters, the block was tapped I just had to buy the brackets. They came in a kit from comp cams.

For the 383 part - I used a forged rotating assembly from scat. https://www.scatcrankshafts.com/product/1-41755bie/

You need aftermarket or a set of older aluminum Corvette heads, in my opinion. You can get vortec heads but you will be limited to intake manifolds, I do think someone makes some little inserts that allow intakes to be used on both bolt angles, but not sure how good they are.

Last thought is the fuel supply. You currently have a 45 psi electric in-tank fuel pump, you'll have to reconfigure your lines & sending unit. My old block did still have the mechanical fuel pump provision, it was just blocked off. Make sure your cam has a fuel pump lobe if you go this route.

Hope this helps.

 

[78Delta88]

...
You need aftermarket or a set of older aluminum Corvette heads, in my opinion. You can get vortec heads but you will be limited to intake manifolds, I do think someone makes some little inserts that allow intakes to be used on both bolt angles, but not sure how good they are.
...

Number on the Corvette heads ...118? D port and angled plugs? Good choice for affordability. On The inserts, kits are available but most intakes I have gotten recently all included the kits.

 

[ELCAM]

Number on the Corvette heads ...118? D port and angled plugs?

That sounds like the 10088113, Aluminum, raised D port exhaust, 58cc, Angle plug and 1.94/1.50" Valves.

 

[78Delta88]

That sounds like the 10088113, Aluminum, raised D port exhaust, 58cc, Angle plug and 1.94/1.50" Valves.

Yes. ...113, 1.94/1.50, 58 cc

 

[Yav8]

There are all the numbers. Freshen up the stock vortec and reuse the stock roller cam lifters dog bones and spiders. Only up grade, might be a set of 1.6 roller tipped rockers. This set up makes on sweet street motor. You can even use the stock valve springs if you want. Use a shim head gasket for a little bump in compression or use the stock one and still run it on 87 octane. Here in Wisconsin we can get 91 with no eth added. Help keep the junk out of the carb. If you want FI then use the stock truck and then grab the trans and put it all in if you are into that.

 

[Bar50]

For what it's worth, a Vortec style or most any 1 piece rear man 350, add the OEM roller lifters and flat top pistons is an epic base. A guy can add an LT4 Hot Cam copy or Mercruiser/marine cam, with the Vortec heads you are looking at a 400+ horsepower heart pretty easy.

By the way, LS1 and 93-97 LT motor and Vortec motors all use the same roller lifters.

 

[Yav8]

For what it's worth, a Vortec style or most any 1 piece rear man 350, add the OEM roller lifters and flat top pistons is an epic base. A guy can add an LT4 Hot Cam copy or Mercruiser/marine cam, with the Vortec heads you are looking at a 400+ horsepower heart pretty easy.

By the way, LS1 and 93-97 LT motor and Vortec motors all use the same roller lifters.

For what it's worth, a Vortec style or most any 1 piece rear man 350, add the OEM roller lifters and flat top pistons is an epic base. A guy can add an LT4 Hot Cam copy or Mercruiser/marine cam, with the Vortec heads you are looking at a 400+ horsepower heart pretty easy.

By the way, LS1 and 93-97 LT motor and Vortec motors all use the same roller lifters.

Not all the one pieces seal blocks are set up for a roller cam. 1986 on up were mostly set up for a flat tappet cam 638 blocks. I not a factory roller it can be upgraded with a retro fit set up (stupid money). From 1996-2000 all the blocks were rollers 880 castings. You can spend your money anyway you want. As for pistons I always used the stock ones and just used a steel shim head gasket. The 880 pistons are short skirted lite weight and use the thin metric ring package. No $200 set of pistons and rings and then to have some shop put the pistons on the rods. Save the money for a cam and valve springs. That marine cam 395 and a blue strip will make 350hp and 400tq same as the GM Ram Jet motor and 1.6 rockers. That Gm Hot Cam and 1.6 rockers is a real sweet motor.