Ok, I'm getting a 355 from my buddy and the block itself came out of a 70s truck or camaro, he doesn't remember. Will my 700R4 bolt up to that? What flywheel? Starter?

I'm thinking of ditching the EFI system and just throwing the carb'd motor into my car. Would this cause more of a headache? How easy/hard is this? Anyone who has done this, please chime in and elaborate on you're swap. Also, what numbers do you think this motor would make...

355
Holley Contender single plane
Holley 750DP
ported heads, 3angle, valve cut
roller rockers
.500 degree cam (dont know which yet)
accel cap, coil, rotor
full exhaust - hooker, 3"ypipe, 3"cat, chambered mufflers (similar to gmmg)
700r4 with transgo shift kit, 2400 converter
3.23 posi

pic of the motor



I have a bunch of EFI stuff to use as this was my initial plan, but having all this fall into my lap for very little money, I'm starting to think I can't pass this up and save a few bucks yah know? Also, I plan on swapping out the stock heads for some Trickflow KD's or AFR 190s, as well as change that contender intake to an air gap or something. Give me you're thoughts!

 

There's a tech article on switching from EFI to carb on the TGO home page. A sticky at the top of the Carb forum contains the link, if that's easier. There are pros and cons to both carb and TPI, so in the end, the decision is yours (I typically advocate running what you've got, FWIW).

Yes, your transmission will mount to the 350. A 153-tooth (12-3/4") flexplate and your current starter (or replacement of same application) will work fine.

 

sweet thanks!

 

SO what's the diff between the pre 85 block, and the after 85 block.. is it just the heads, and how the covers bolt? i have a 305, and found out i could get a 350 for about 100 bucks. may need some rebuilding, but i think it's kinda old. 79ish i think.. what kind of problems would that bring being i have a 91 block?

 

The 70's motor will connect to the 700R4 just fine - may need a different starter as there are flywheel differences - 153 teeth vs. 168 teeth on the flywheels - I just got an older starter for the older motor - it's a tad larger in size, but works fine.

Going carb means an HEI dizzy, a carb intake, a 3-port return style regulator, the right linkage for the TV cable to geometrically connect to the carb linkage, and a lockup mechanism for the torque converter - most are vacuum controlled. I also used an external fan control switch rather than the fan switch in the block (with the sensor that pokes between the radiator fins). That's about it.

Plan on other things such as motor mounts, tranny mounts, etc. while your there. Also, now's a good time to get higher stall converter, replace the front and rear seals on the tranny, change the tranny fluids, filter, and pan gasket, and a million other small things while your there (shift kit plans?).

Think about what gets removed, and plan ahead to repair and replace and upgrade other things while you've got half the car apart.

 

Starting in 86 the blocks were one-piece rear main seals the heads were center bolts and some blocks had roller cams, you can tell by looking in the lifter valley and see the taller lifter bosses. 85 and earler blocks two-piece rear main and the dipstick can be on the driver or passenger side of the block. I put a 71 355 in my 84 everything swapped over fine it looked like the origanal motor except now the dipstick is on the drivers side.

 

has any one done an older 350 into a 86+ 3rd gen?

 

It isn't any different. You just have to change the flywheel or flexplate for the 2 piece rear main seal.

 

Yeah I plan on upgrading the tranny while the engine install process starts. Along with rigging up a lock up switch for the converter, installing a fan switch, heads being ported, bigger cam. The guy said there was already internal work done besides the cam so who knows for sure until I rip it apart. Do I need to change my rad? I was reading the tech article and the dude said the 3 way regulator from mallory is junk and to just get an electric fuel pump outside the tank and have a regulator in the engine bay, how hard is this to get working? What wiring is needed? I want 300-350rwhp with this motor, what cam/intake should I use? I already have a Holley 750DP and Holley Contender intake, comes with motor, but was thinking of upgrading the intake. If anyone thinks otherwise, please enlighten me. Thanks for any input!

Oh, when removing all of you're wires and electronic crap from under the dash and in the engine bay, what did you keep?

 

Not exactly. One-piece RMS yes, but roller lifter cam and center bolt heads didn't come until the 1987 model year.

 

So that no one reading this is mislead - No where in the tech article does it say "junk" - it says personal preference. Not that I'm any long term user and expert, but I'm having no problems with my Mallory regulator at all, and haven't heard of anyone having any - and it is alot easier to do if your existing pump still works fine - the Mallory (or whatever brand) does mount under the hood (or where ever you like to mount it). Of course - you may want to wait until someone with 350 rwhp chimes in on this - I'm not sure what my hp is at the moment on my 350.

Also my stock radiator is working fine as well - so no need to do that at the moment (if you'd like to save that cash for another "now" necessity - and can swap to a better radiator later when the stocker poops out) - I'm a "don't fix it if it ain't broke" kinda guy - save the cash up front and try the stock radiator to see - everyone's setup is different (unless your just really dying to show everyone a $300 radiator under your hood).

On the wiring, I attached what was necessary, and left the rest there but disconnected for the time being, just to be safe. I didn't rip anything from under the dash (why go to the trouble) - my ECM is even still there, just disconnected (later, when I'm sure everything is good, I'll set fire to it, and dance naked around it).

I keep saying later - cause after my swap last November I found my tranny was slipping, so I'm dysfuntional right now as my tranny is undergoing a rebuild.

 

Alright man sounds good. Yeah, better to be safe then sorry with all this wiring mess. I was planning on trying the mallory regulator anyway as it's cheaper than buying a new pump. Like I said, 300-350 would be perfect for me. Anything higher would just ruin my chances with autoX and track use.

 

Hey man, I just did this same swap this winter. Where are you located in Toronto? I ripped out the entire harness comming from the passenger side. Sold the ecm, intake etc as a whole package, and got a decent amount of coin for it. So DO NOT cut up the harness, as it is worth money to the right person.