another question for ya all

oh and I forgot to thank all of you for the help on my last question..

ok how are the 350 and 305 different besides the power of course like will the intake manifold off of a 305 fit on a 350 for example cause it sure looks like it will.....

Reply to
TERRY
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A 305 and a 350 are in the same basic engine family, as are all small block chevys.

The differtances are heads, bore sizes, cranks, crank journials, mains, ect. Internially they are different, and some items DO NOT interchange (IE 350 Crank in 305, or 350 heads on 305).

A 350 is a member of the 4 inch bore side of the small block family. This block can take numerios cranks to either rasie or lower the displacement via stroke.

With a 305 you do not have any options to change displacement other then bore enlargement. You are limited as in which heads you can run (they are 305 specific).

When it comes to externials, such as water pumps, mechanical fuel pumps, accessiories. All that stuff is interchangeable. You can even use a water pump, pulleys, and accessiories off of a 4.3 V6.

Things that won't work on a 305: 400 Small Block ballencers or flywheels, some starters, 4.3 V6 distributors (since it's for a 6 banger), and some other engine year/application specific stuff.

Charles

Reply to
Charles Bendig

Actually there is a 335" stroker kit available for the 305, although why anyone would stroke a 305 with that small bore and restrictive head design is beyond me.

-Matt- "..."

Reply to
matt borland

And IIRC, actually stroking it is one of the only options (other than N2O, supercharger or turbo) you have. My understanding is that the casting doesn't allow for any significant increase in bore size without hitting the water jacket. Now, my understanding is that you could use the same supercharger or turbo on the 305 that you would on the 350 so you could put the forced induction on it and then later you could build a 350 to put in it. It would however have been interesting to see what one of those Coates ball valve systems could have done to a 305. It would have solved the valve shrouding problem that makes it so hard to get any real performance out of the poor little things.

Reply to
Cyrus Welch

A few months ago I was talking with another local shop owner, who does work turbos. We were talking about my V-8 Typhone 'Clone' Idea. He showed me some data from where they did a 305 Twin Turbo S-10 pick up for a customer. I was pretty impressed with the numbers. That S-10 was in the 10's in the quarter mile. Yet it had been lightened a bit body wise, and uses a tube frame. Not a driver by any means, it's a trailer queen show truck with more in audio equipiment then some of you ever invested in tools.

The problem with cost effective turbo systems for SBC's is they don't exsist. Gail Banks stopped making them years ago, so unless you want to spend big bucks for one, your left tying to peice it from Honda Civic kits, and buick GN parts.

My idea is a simple one. Find a clean 4x4 Chevy/GMC S-10/S-15 Blazer/Jimmy. Switch the parts needed to lower it to Typhoon ride height, and handling. Convert it to AWD (a simple transfercase replacement), use a 3/4 ton Full size front diff (to handle the increased stresses). Use a 400 small block with Twin turbos (one per cylinder bank) and TPI injection. Parts costs alone will probably run over $19,000.

Charles

Reply to
Charles Bendig

Who offers this kit? Depending apon the application & costs, for cars under 3,300 pounds.... Engeeners Brain, Inventors Budget...

Charles

Reply to
Charles Bendig

Actually there is a kit out there from a company in Utah that actually replaces the muffler with a turbo. All the reports I have seen say that it works quite well. It may be far easier to adapt that unit than try something else. And I just saw an episode of horsepower tv where Banks said they were doing twin turbo stuff that would bolt onto almost any SBC. I might have to convert to TPI first, but it sounds like one or the other system may be doable.

Reply to
Cyrus Welch

Any Turbo system with the impeller at that great a distance from the engine is going to be a joke. First you have to take in to account the decreased speed of the exhaust gasses the further from the engine they get. Hot Gasses flow faster then gasses that have cooled. Not to mention you will get 6 times the turbo lag with something like this. Then their is the extra weight issues. I don't care what a chassis dyno says, you will see the weight in the 1/4 mile times. Charles

Reply to
Charles Bendig

I read an article in CHP magazine about this subject. It seems to be on the level. Link below. Getting the turbo out from under the hood looks to be a great idea.

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...Ron

--

68' Camaro RS 88' Firebird Formula 00' Mustang GT Vert
Reply to
RSCamaro

One would think so. And this has always been the assumption. However all the reviews I have seen on this say this is not the case however take a look at this review

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about it. One of the things I seem to find on this thing is that it needs no intercooler as the air pipe to the engine provides that. It also seems the turbo itself is designed for running where it is, and since the temp is lower at that distance supposedly the turbo still works fine but will last longer due to the lower temps.

Reply to
Cyrus Welch

IIRC it's an Eagle kit. 99.99% sure.

-Matt- "..."

Reply to
matt borland

=A0 "The differtances are heads, bore sizes, cranks, crank journials, mains, ect. Internially they are different, and some items DO NOT interchange (IE 350 Crank in 305, or 350 heads on 305)."

Actually, the 305 and 350 share the same crank from the factory 3.48". Also, the heads from a 350 will fit just fine... the only thing to concern yourself with is valve clearance. I swapped a set of L98 heads onto my 305 a few months ago,

With a 305, you'll want to to limit the intake valve size to 1.94 (which is what most 350's came with from the factory anyway), unless you buy an angled aftermarket set (expensive). A 2.02 intake valve will obviously not clear the 305's limited bore though....

Reply to
BowTieBubba

While the storke of 3.48 is the same, the Cranks are not.

Also I hope you enjoy a compression ratio of about 7:1 with your 350 heads. If you used the wrong head gaskets, enjoy the damaged bores as well.

Charles

Reply to
Charles Bendig

He has a point since the 305 heads have 58cc combustion chambers and the 350 heads are most likely 76cc, or at best 64cc before milling...

-Matt- "..."

Reply to
matt borland

=A0 "Also I hope you enjoy a compression ratio of about 7:1 with your 350 heads. If you used the wrong head gaskets, enjoy the damaged bores as well"...

Oh my goodness, didn't mean to rain on you're parade Charles lol. Just to 'elaborate' though, I swapped a set of L98 heads onto my LO3, and tossed it's original swirl port design.

The heads were cut, compression is good, and the block's bores are just fine.

As for different cranks (in reference to 305 vs 350, as opposed to

1987-up one piece & 1986-down two piece, rear main seals), kindly explain yourself...
Reply to
BowTieBubba

"He has a point since the 305 heads have 58cc combustion chambers and the 350 heads are most likely 76cc, or at best 64cc before milling..."

Yeah, the L98 heads were milled. I wasn't seeking too high of a compression ratio (which is why I avoided the LB9's) because I'm supercharging it this summer....

Reply to
BowTieBubba

First for 350 heads to clear on 305's you have to use the thicker type head gaskets. This allows extra clearance. Yes .010 makes a huge differance in such a case.

As for the Cranks, not only do they carry different part numbers for the same years of 350 & 305, they are different.

305 Cranks do not have as thick throws, nor or they as strong as a 350 Crank. Yes 350 cranks come in a few flavors too (large vs small journial, forged vs cast).

When it comes to making high power with a SBC 4 inch bore blocks with either type (factory or machine shop splayed) 4 bolt mains are perfered. Cost wise it costs less to build up a 350 (from a 'core' long block) then it does a 305.

I have had people buy both 305 heads and 350 heads for their ideas of swaps. When things go wrong (not a problem with the parts I sold them, which were tested used replacement parts), jad these people come back to me. It's not my fault some 305 heads on some 350's will give you 15:1 compression ratio, or some 350 heads will give you as low as 6:1 on a

305. Nor is it my fault that 350 valves do not always clear the bores on 305.

So with me, 305 heads are 305 heads, 350 heads are 350 heads. If I want a better then stock flow rate, I call Jegs or Summit and get a set of iron heads (dart & world products both make them). then send them to a machine shop and have the seats cut for the valves I chose, as well as have everything tested and assembled. Even new casting can fail a pressure check (rare yet does happen).

Im sure if you wanted to spend the right amount of money, you could have a 305 sleaved for sixty over slug (piston) or larger. You could probably have the block and a 400 crank machined to work together, and even get some 2.02 intake valves to clear. (334 CID give or take a few). For that same amount of money Ill build a 383 with aftermaket heads, and a large (almost obseanly over cammed) bumpstick. Charles

Reply to
Charles Bendig

guys all I wanted to know was is can I take the tune port off a 89 305 and put it on a 86 350 will the bolt holes line up ?

Reply to
Terry

Intake wise, Yes a 305 and a 350 use the same stuff. Yet there is a Year difference in Head type. 1986 and previous heads have a different angle to the bolt holes then 1987 and later heads, regaurdless of small block displacement.

You can angle the holes out and have every thing work. Charles

Reply to
Charles Bendig

Reply to
Terry

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