chevy 305 to olds 350

[vladj]

so my cutlass came with a chevy 305 in it. Im tired of trying to find a cheap SBC but i can pick up a running 350 rocket and trans for $200. how hard would it be to swap it and what will i need to change?

thanks;

vlad

 

[3XBrownCutty]

Starter is on the opposite side, different motor/frame mounts, not sure if the fuel line is on the same side or not... those are just some basics. might need to lenthen or shorten some wires depending...

 

[axisg]

yeah, If memory servies everything is opposite. Fuel Pump, Fuel Line, Battery, Starter. It would go quicker by getting a car with a 307 amd swapping over the wiring harness and engine brackets to your car.

 

[FE3X CLONE]

Fuel pump is on the passenger side of the block on an Olds. Aren't Chevy's the same way?

You'll need the frame mounts and engine mounts from a 307 car. The mounts should go in the last set of holes on the frame towards the firewall.

Battery is on the drivers side along with the starter. Oil filter on the passenger side.

Assuming a Chevy engine had the fuel pump on the passenger side, then I would think you should be okay with the fuel lines.

Starter wires would probably need to be shortened.

 

[joe_padavano]

Given how many people on this forum are convince that swapping an SBC into their Cutlass is the only possible choice, there must be millions of 307 frame brackets available out there. Find someone doing the 307-to-SBC swap and just trade them the Chevy mounts and associated parts for their 307 Olds parts. Also note that the 307 frame mounts are just slightly different from side to side, so be sure you get them installed on the correct sides.

 

[Blake442]

When I went from my 307 SBO to a 350 SBC, all I had to do was swap the frame mounts, shorten the rubber fuel line to the fuel pump, lengthen the wires from the battery to the alternator, and from the harness to the starter. And exhaust of course. That's it.

To go from SBC to SBO, all you really need to do is swap the frame mounts, and replace the rubber fuel line that goes from the hard line poking out of the front of the frame with one that's a little bit longer. The fuel pump is on the same side on Chevy's and Olds's, but it mounts a little higher on the Olds, so that's why you need the extra length.

 

[j_tizzle_84]

i have the frame mounts from my 307 olds that i just took out as well as the whole motor if you need anything from it let me know. jt

 

[jae]

The ease of the swap and shortening / lengthening of the wires & lines will depend on what the orginal engine was and what was cut / spliced / hacked to make the 305 work. Also the differing locations of some items not listed above, like the oil pressure senseor, heater hose hook-ups, I want to say A/C compressor but not 100% sure?.

What transmission do you have? Remember, the SBC and the Olds have different bolt patterns so if the transmission is not a 200-4R then the bell-housing pattern is different. Hopefully the transmission connected to the Olds 350 is in good working order, just in case.

If running a quadra-jet know the inlets are in different locations between the Chevy and Olds so it really isn't just abolt-on affair, but easily modified.

I would take j_tizzle up on his offer and get as much from the 307 as you can (whole front accessory drive), if not the whole motor.

 

[vladj]

thanks guys. im just trying to get a hold of him. the engine is a late 70's engine so what would i be looking at for HP? and how hard is it to upgrade for more power(would like to be somewhere around 350-400 hp)?

thanks;

vlad

 

[dan2286]

thanks guys. im just trying to get a hold of him. the engine is a late 70's engine so what would i be looking at for HP? and how hard is it to upgrade for more power(would like to be somewhere around 350-400 hp)?

thanks;

vlad

It depends on what year motor it is. If it is late 70's it is definitely a smog motor. If it is 77+, it is a windowed main motor which is not as strong as earlier blocks. You won't be able to get that kind of power without a decent amount of money. Olds engines are better at making tons of low end torque and they don't like high rpm's. Someone correct me if I am wrong, but I believe the heads will take a bunch of money to be able to flow enough for that kind of power. I think the most important things to start with is raising the compression ratio by getting different pistons and shaving the heads and block. Of course the cam needs to be changed also. You have to realize that these engines are not the same as a Chevy and it will need to be built different. Your best bet is to find a machine shop that deals with Olds engines on a normal basis and get some ideas from them. Do not listen to people that have never dealt with these engines, you will be disappointed with the end results.

Take a look at the engine build sections on ROP and you should be able to get some ideas from that. http://www.realoldspower.com/phpBB2/vie ... c803fb17e1

If you don't have any Olds machine shops around you or can't find one, try joining some of these forums and ask for advice on who to use and what you need to do to your engine.

http://www.oldspower.com/vb/index.php
http://www.realoldspower.com/phpBB2/index.php
http://highperformanceolds.com/phpbb2-1/index.php
http://classicoldsmobile.com/