FOX-GTA_89

One of my friends wants to sell me his 1974 350.
My 305 tpi broke (bottom end is shot..) and i want to swap the short block for the 350.

The engine is out of a mid-70's chevelle.

Will my TPI system be a direct bolt-on?

What heads are the best, the stock ones on the 350 or the ones on my stock LB9 (1989)??

TIA!!

ME Leigh

The 350 heads are probably crap.

F-BIRD'88

I would swap the 305 TPi heads onto the 350 also.

The stock cam in a 1974 350 is quite small

this one will work well with TPI
Crane H-262-2

FOX-GTA_89

and this cam can work with stock computer witout special prom???

and the mass aif flow /sendsors /flywheels will they fit...what else is gonna be a problem?

Vader

Unless the crank has been converted, the flywheel from your '89 won't fit up properly.

The compression on the "smog-dog" engine is way too low, even with your heads, sine the old 350 probably has 12-14cc dished jugs.

And the cam is not likely a suitable grind for a TPI. Heck, it probably wasn't really siutable for the old 2GC or 4MV carb that was bolted on over it.

Add to that the fact that you'll be converting backward to a flat tappet cam, and all you have is a good block - That is, if it doesn't have "The Problem", or "The Other Problem" as was so common in mid-'70s SBCs.

Is it starting to look like less of a bargain yet?

FOX-GTA_89

so a tpi with this base is not a good idea so i should carbed it?

SweetS10v8

Since you 305 is broke and you were going to have to rebuild, I would get the 350 and just rebuild it like you were going to have to anyways, with the 305.

Get some flat tops, and a 210-212 dur @ .050 cam and use the 305 heads since they have the correct bolt pattern for your tpi, and rebuild it so its fresh.

Vader

The point was that even a carburetor isn't good with that engine. It never was good back in the '70s either.

Using the 305 heads might be O.K., but they'll require a little work first. Your '89 heads have the modified center intake bolts, so an original '70s carb manifold isn't a direct bolt on. The valves in your 205 heads should be enlarged for the 350. And depending on your castings, port work might be effective and beneficial. Spring and stud rework is always recommended.

The biggest disadvantages are the pistons, heavy rods, and lack of a roller cam provision. Unless you want to rebuild the 350 completely as just a core, you might want to rethink the idea and it's true cost. Has anything been done to the engine by your friend to improve it, or is it simply a stock '70s 350?

F-BIRD'88

This cam is very likely to run fine using a stock computer
with a stock prom. (especially a MAF system)
Call Crane cams tech to verify this.
You may want to add a adjustable fuel pressure regulator. It will be a nice improvement from the stock little 350 cam and will work well on a TPI motor.
You'll need new hyd flat tappet lifters and a new timing chain and gear set for the 350.

The 305 manual trans flywheel will not fit.
You'll have to get a 350 manual trans flywheel from a 60-70's early 80's 350 with a two piece rear main seal.

All else should fit fine.

You'll be a step ahead using your 305 heads on the 350
(intake fitment and higher compression ratio) but can improve these heads nicely for more power with larger valves and home porting.
and a new multi angle valve job.

SSC

The 350 will have a DSL dipstick tube, that may be a problem if you have the stock exh manifolds, headers will cure that problem but some people bend the dipstick tube around thier factory 3rdgen manifolds. I think thats cheezy.

As long as the engine is cheap like in the $200 range and doesent need rebuilt it might be worth it, any more then that and its a draw since all the time and effort required to use this 350 wount yeild much more umph then your 305 before it died.