palric

iTrader: (1)

Well I guess we've all heard this before time to do it again -- I found an early 70s 350 4-bolt with steel crank and rods still attached, for very cheap ($50) in fact from the same guy who has the vortec heads I spoke of on another post.

It has never been rebuilt. It is not a roller block of course. I would appreciate some opinions please:

1) what about roller vs. non-roller ? I know the cam solution is alot cheaper for the non-roller I also know they are less aggressive and perform differently than rollers. That is about as much as I know about the behaviour diffs between the two. I am familiar with the physical diffs.

2) what is the deal on sinlge rear seals vs. two-piece rear seals ? Does this matter to us ? To my 5-speed ?

3) can't remember if I have to change my flywheel, starter, etc when I swap out to a 350 ?

thx in advance for your comments,
RP.

nblanchard

I'm not sure about the single vs two piece rear main seal, but I think I've heard of using a different flywheel like you mentioned.

As for roller vs non roller, roller all the way dood, catches revs quicker, more precise lift.... go for roller.

16th owner

I agree. Definitly go roller and if you don't mine checking the valve lash once in awhile, go mechanical. Talk about revs

88redxtsy

I'm no expert but here's my .02cents.

1) The starter is fine. The auto's have larger starters than the manuals. The read this on the auto to manual swap. Apparantly the small starter is need for clearance issue's. Than again I've heard that the larger starter will fit with the manual. Either way, I think your fine.

2) About the 2 piece rear seals, I've heard that they are more prone to leaks than the one piece. Which is why I'm looking for a 350 one piece main seal asopposed to two.

Again this is based on not experiance but what I've read through this web-site. Do a search on the main board. Very resourceful.

Daz

iTrader: (1)

Which roller Solid roller or Hydraulic roller??

Between thirdgen hydraulic rollers(87 and up) vs. 70's 350 hydraulic.You dont need to re-do the valve lash in xxx miles..Do the adjustment ones and done(Its not like the solid roller cams)..Roller cams can have higher lift and duration and still (steep)have good low end response..Since the roller lifter follows the lobe you can have steeper lobes..Roller lifters also last longer than hydraulic..

OK heres a comparo

Hydraulic lifter/cam
1)cheap
2)simple
3)less parts to break

Hyrdraulic roller lifters/cam
1)less drag means more power
2)camshaft last longer
3)lifters last forever
4)more low end power

Solid roller
1)everything the same as hydraulic roller..except for constant adjustment and noise
2)lifters are lighter than the hydraulic counterparts which means more power and capable of higher RPM
3)simple


Daz

Ratchet

IMHO If you look at dollars per horsepower the 70's 350 block with a streetable hydralic lifter cam is the way to go.

The 2 piece rear main seals in these engines do leak if installed improperly however you should get upwards of 180,000 kms without it leaking. The one piece is a better unit but that block will be more expensive to rebuild.

Roller cams are the best but unless you are shooting for the 600 horespower neighbourhood not required and way too expensive.

I would go with your intake system. the 350 block decked to zero with flat top cast pistons (forged not required under 500 horses) a set of 496 castings for the heads. 496 are the old fuel injection heads that made 350 horsepower on a 327 with a hydralic lifter cam. The 496 castings are the angle plug version of the old camel hump heads have 62 cc combustion chambers and work like stink. If you do a mild bowl porting open the restriction up at the pushrods and match the ports to the gaskets. This combination should net you about 400 real horses with a 460/470 lift cam and good exhaust system.

Ratchet

Forgot to tell you that the fullie heads also have all the tapped holes in the front to mount the accessories.

Ric

Kevin Vandevenne

iTrader: (3)

I think the biggest advantage of a roller cam has only briefly been pointed out, and that is that with a roller, you don't need a radical amount of duration to get a high amount of lift. You can easily get .525" lift on a very mild roller cam, but to do that on a flat tappet cam, the cam would be outside the range of a daily driver, and certianly not emissions compliant.

You'll also have to look into mating the T5 flywheel to the older style crank. It would be an easy swap, since the T5 was out in 83 (i think) and they didn't convert to a 1 piece seal until 86. I'm pretty sure all you would need is an older style flexplate, but you may want to look into it.

For $50, I'd buy it even if you don't decide to use it. If it does have the steel crank (factory forged job), it would be worth some coin.

ninety1TAgta

One thing no one really mentioned (although kevins emmision cam comment reminded me of) was that you should consider doing a different crank in the procces so you can got for hot rod status. It would be alot easier to build an engine for hp if you didnt have to worry about the tailpipe puffer...

johnyIROC

Roller is the way to go 100%. The ramp angles can be WAY steeper with a roller cam.

This means you can flow mad amounts of air WITHOUT that nasty overlap..... I know everyone thinks that it's all about the chunky lope, but that gets old when your brakes don't work and your car runs like *** before 3k.

nblanchard

Yeah... I agree there... just think of the mechanics of flat lifters over the mechanics of a roller... I say it is well worth the money for roller.

Why do you think Mustangs can go with such a nasty cam with out sacrificing driveability? Cause they have a full roller engine.

SmallTires

iTrader: (4)

Although not feasible for most a vacuum pump solved all my issues due to a large overlap cam. Seriously people just aren't will to spend money to make things work properly. I went with a roller cam to have better low end driveability but went with more overlap to have that top end power. Not the best for a daily driver but the compromise was worth it. Sure the pump was not cheap but considering I have nearly $9k into my car what the h*ll was the extra $250 gonna hurt. You gotta pay to play...

Sinister Z

???

Eric2ndGen

Yo, guys, wake-up. You're responding to a thread that is over 4 years old that some sh!thead 'bumped' to get his postcount up.

Perhaps a Mod could go and delete all Donald1992's post in here so that they all fall back into the appropriate "archive" from where they appeared.

Sinister Z

I didn't even realize that...but I have seen quite a few "bump" poat all over, that for the heads up! that guy must be