I am planing on doing an engine swap on a 85 Trans Am with a 305.

We bought a 84 Camaro for parts and the engine. The guy we bought it from about it years ago as a project car and never got around to it and apperently the owner before him did the same thing.

Well the guy we bought from said it had a 350 in it and thought it was a 70's 350.

Well we ripped the engine out and looked at the numbers. One of the numbers said 460778. I looked that number up on the intertnet and it said it is a 305.

My step dad looked at it and said it is a 4 bolt main.....I look on the internet and everything says the 305 is a 2 bolt.

Any one have any ideas?

 

Some 305 truck blocks have 4 bolt mains.

 

The guy thought it came out of a Blazer. So I guess it has the same HP and Torque?

 

www.mortec.com/castnum.htm

CASTING#.....SIZE...YEAR...MAIN CAP BOLTS....NOTES
460778.....305...78-79...2 or 4, some Canadian assembled heavy duty truck blocks have 4-bolt main caps

 

Right......But is there any HP difference in a 305 2 bolt and a 305 4 bolt?

 

You'd never know the difference unless you pulled the pan off to count the bolts.

 

Horsepower output has everything to do with the cam, heads and induction, and nothing to do with how many bolts the center 3 main caps have.

 

I see.....I was just wondering because it seemed like alot of the 350's with a 4 bolt had more hp.

 

350's came in all sorts of varieties. The truck engines tyically had 4 bolt mains, but often had 2 bbl carbs and small 1.72" intake valves - very low power, but still had 4 bolt mains.

At least up through 1976, all 350's with 4 bbl carbs had 4 bolt mains. Some of them were still pretty low on the power side. The 3rd gen 350's, which were all 2 bolt mains, had more power than a lot of the earlier 4 bolt main 350's.

So, you can't draw any good conclusions based solely on the type of mains.

 

How much HP it had from the factory doesn't have a whole lot to do with how much HP it has after being modified and put into a different application.

 

Yeah I know the engine is only rated at like 140 HP. Even after it TPI setup is put on it I dont think it will reach 200 HP.
I spent $300 and my step dad paid $300 on the car cause I wanted the engine and he wanted other parts off of it.

I have a 93 Z24 Cavalier V6 that would probaly be faster then the TA then.

I think I am going to save up another $300 and see if I cant find a 350 pre 1974.

 

I would go ahead and look for an 87+ 350, you will have the provision for a roller cam which will produce more power and also a 1 piece RMS vs a 2 piece which will end up leaking.

 

What's the attraction of a pre-1974 block?

 

1968
350 V8 (2bbl) 265 bhp @ 4600 rpm, 355 lb-ft @ 2800 rpm.
350 V8 HO (4bbl) 320 bhp @ 5100 rpm, 380 lb-ft @ 3200 rpm.


1970 1/2
Disp Carb HP Torque C/R
350 2bbl Roch 250@4800 345@2800 9.0
350 4bbl Roch 300@4800 380@3200 10.25
350 4bbl Holley 360@6000 380@4000 11.0
1971
350 2bbl Roch 245@4800 350@2800 8.5
350 4bbl Roch 270@4800 360@3200 8.5
350 4bbl Holley 330@5600 360@4000 9.0
72
350 2bbl Roch 165@4000 280@2400 8.5
350 4bbl Roch 200@4400 300@2800 8.5
350 4bbl Roch 255@5600 280@4000 9.0
73
350 2bbl Roch 145@4000 255@2400 8.5
350 4bbl Roch 175@4000 270@2400 8.5
350 4bbl Roch 245@5200 280@4000 9.0
1974
Disp Carb HP Torque C/R
350 2bbl Roch 145@3600 250@2200 8.5
350 4bbl Roch 160@3800 245@2400 8.5
350 4bbl Roch 185@4000 270@2600 8.5
350 4bbl Roch 245@5200 280@4000 9.0
1975
Disp Carb HP Torque C/R
350 2bbl Roch 145@3600 250@2200 8.5
350 4bbl Roch 155@3800 245@2400 8.5
1976
Disp Carb HP Torque C/R
350 2bbl Roch 145@3800 250@2200 8.5
350 4bbl Roch 165@3800 260@2400 8.5
1977
Disp Carb HP Torque C/R
350 4bbl Roch 165@3800 260@2400 8.5
1978
Disp Carb HP Torque C/R
350 4bbl Roch 170@3800 270@2400 8.5
1979
Disp Carb HP Torque C/R
350 4bbl Roch 170@3800 270@2400 8.2
1980
Disp Carb HP Torque C/R
350 4bbl Roch 170@3800 270@2400 8.2

87
OHV V-8 350/5.7 210@4000 315@3200 TPI

88
OHV V-8 350/5.7 225@4400 330@3200 TPI

89
OHV V-8 350/5.7 225@4400 300@3200 TPI
OHV V-8 350/5.7 235@4400 340@3200 TPI

90
OHV V-8 350/5.7 235@4400 340@3200 TPI

 

You realize to get those numbers, you will have to find a complete motor heads intake etc etc, and then if you have emission testing, by the time you make it legal it will have probably less HP than the 87+ do. Plus the 300HP motors were only in certain cars, not every Chevy with a 350 pre 74 were built to do that.

I still say you would be better off with an 87+ block just for the reasons I stated, one you can keep them computer controlled and emissions friendly (again, if you have emission testing) and the roller cams will give a boost in HP over a flat tappet with less wear on the cam and lifters, promoting longer life, plus fuel economy will be higher than a pre 74 engine as well.

 

In '71 they dropped compression ratio, the first shot across the bow in the emissions salvo to come. Up to this point, cams were known to be soft and have lobes wear down. Very few good head choices for performance.

In '72, they changed the HP rating system from a willie-nillie gross flywheel system (basically, anything they wanted to say) to a net flywheel rating (with induction, exhaust, and accessories, installed on the dyno as they would be installed in the car).

In '75, catalytic converters and unleaded gas came on the scene. About the same time, Detroit in general went down the tubes, quality was poor, performance was a dirty word, etc. No good head choices for performance.

Early '80's quality was turning around, but still questionable.

Mid-late '80's, quality and performance picking up again.

All of this is really silly, though, because as has been said already, power is dependant upon things you'd change around the block, anyway.

 

Here are some numbers for 350's

1968
350 V8 (2bbl) 265hp 355 lb-ft
350 V8 HO (4bbl) 320hp 380 lb-ft
1969
350 V8 (2bbl) 265hp 355 lb-ft
350 V8 HO (4bbl) 320hp 380 lb-ft

1970 1/2
Disp Carb HP Torque C/R
350 2bbl Roch 250@4800 345@2800 9.0
350 4bbl Roch 300@4800 380@3200 10.25
350 4bbl Holley 360@6000 380@4000 11.0
1971
350 2bbl Roch 245@4800 350@2800 8.5
350 4bbl Roch 270@4800 360@3200 8.5
350 4bbl Holley 330@5600 360@4000 9.0
72
350 2bbl Roch 165@4000 280@2400 8.5
350 4bbl Roch 200@4400 300@2800 8.5
350 4bbl Roch 255@5600 280@4000 9.0
73
350 2bbl Roch 145@4000 255@2400 8.5
350 4bbl Roch 175@4000 270@2400 8.5
350 4bbl Roch 245@5200 280@4000 9.0
1974
Disp Carb HP Torque C/R
350 2bbl Roch 145@3600 250@2200 8.5
350 4bbl Roch 160@3800 245@2400 8.5
350 4bbl Roch 185@4000 270@2600 8.5
350 4bbl Roch 245@5200 280@4000 9.0
1975
Disp Carb HP Torque C/R
350 2bbl Roch 145@3600 250@2200 8.5
350 4bbl Roch 155@3800 245@2400 8.5
1976
Disp Carb HP Torque C/R
350 2bbl Roch 145@3800 250@2200 8.5
350 4bbl Roch 165@3800 260@2400 8.5
1977
Disp Carb HP Torque C/R
350 4bbl Roch 165@3800 260@2400 8.5
1978
Disp Carb HP Torque C/R
350 4bbl Roch 170@3800 270@2400 8.5
1979
Disp Carb HP Torque C/R
350 4bbl Roch 170@3800 270@2400 8.2
1980
Disp Carb HP Torque C/R
350 4bbl Roch 170@3800 270@2400 8.2

87
OHV V-8 350/5.7 210@4000 315@3200 TPI

88
OHV V-8 350/5.7 225@4400 330@3200 TPI

89
OHV V-8 350/5.7 225@4400 300@3200 TPI
OHV V-8 350/5.7 235@4400 340@3200 TPI

90
OHV V-8 350/5.7 235@4400 340@3200 TPI

Also I read some where in eithere chvey hi performance or Pontaic Preformance or Hot Rod magzine that the TPI system on an older 350 was a lot better the the 350's in the 80s.

Also this article here stats a 30% hp gain with a TPI setup in the first paragraph.

http://www.fuelinjection.com/portinj.html

http://www.fuelinjection.com/portinj.html


Plus my step dad for some reason doesnt want me to get anything bigger then a 350

 

Those HP numbers are as the engine was delivered from the factory. They mean absolutely nothing to you, especially when you consider that even the way they measured HP change in 1973, making comparison impossible. You'll be getting either a junkyard dog or a rebuilt engine, which may or may not look and perform like anything that ever rolled out of the factory.

As far as you're concerned, a 350 is a 350 is a 350.

 

Sorry didnt mean for the double post.
I hit the tab key by accident and I think it submited my reply.

 

Unless you get into the LT1, which is a 350, but is different with a new block casting.

I personally like my LT1...285HP 340 Torque, 10.5:1 compression and it runs very very very nice, plus 25+ MPG on the highway with 3.42 gears.

There is another option for you as well.

 

Klortho

I like that idea but I dont know if I could find one for like $300.

I dont know I am really up in the air about it now.
I called the junkyard that we deal with all the time and never have had any problems with and I asked for a 350....He said what years.....I said it didnt amtter.......he said he didnt have any but he would charge $275-300 for one.

 

Would an LT1 work with the 700R tranny? I really dont have to much money to spend.

 

What about this
http://cgi.ebay.com/ebaymotors/CHEVY...QQcmdZViewItem

I have a 305 TPI and my step dad says all it has is a bad Fly wheel.

 

Replacing the flexplate is about a $35 proposition, if you do the job yourself.

The eBay engine probably came out of a truck, so it probably has the poor heads. It wouldn't be a bad shortblock core, most likely.

 

Cool a 4-bolt 305. Have any pics?

 

I bet it looks an awful lot like a 4 bolt 350.

 

Lol, it will look like magic! Because everybody knows 4-bolts add 50hp. Thats why the LS1 makes so much power, 6-bolts!

 

How much extra power does Willie's splayed 4-bolt 305 have then?

<img src="https://www.thirdgen.org/techbb2/attachment.php?s=&postid=1414640">
<img src="https://www.thirdgen.org/techbb2/attachment.php?s=&postid=1435119"?

 

Splayed caps are actually dangerous because they make too much power. The block can't handle it!

 

They look just like a 302, 327, 350, 400 4 bolt block. Just with the 305 bore size. How do I know? I've got one in the G20.

 

I know that it will look exactly like any other 4-bolt, I just wanted visual evidence of the elusive 4-bolt 305!

 

Can I ask where you heard that?? Splayed caps are much stronger, because splayed caps run at an angle along the walls of the block where the metal is thickest.

 

fa·ce·tious (adj): Playfully jocular; humorous: facetious remarks.
[French facétieux, from facétie, jest, from Latin factia, from factus, witty.]

 

Point taken I didnt read some of the other post .

 

i wouldnt worry too much about stock hp and torque numbers because my 350 im building sucks in the hp range stock... 175 i think which is less than my 305.. but i have aluminum heads, matched cam( read: gigantiragous), matched intake, roller rockers, etc.... power can be built very easily.... oh and i have them all important 4 bolt mains so i think i should be hitting like 1000+ rwhp lol.. j/p

 

Why would you NOT worry about the stock hp. I mean if you can get a 175 hp 350 or a 250 hp 350 for the same price wouldnt you want to get the 250hp 350.

Yeah I understand you can bolt a bunch of things on and get more hp but why not get a higher rated engine first and maybe even spend a couple $$ for the higher rated engine, not a lot more $$.

If you have all the bolt ons and you dont have to spen extra $$ then yeah go for it. But if your going to be spending money on an engine and bolt ons why not get a more powerfull 350.

 

Depends upon what bolt-ons you plan. If just a cam and intake change, then you're right, get the better one. If you're going all the way through it and putting on aftermarket heads, then it doesn't make a bit of difference.

Power is in the cam and heads. Everything else is the supporting cast.

 

tru tru but see in the long run would you rather spend $100 on a low output 350 and spend a lil more on the heads, cam, etc or would you rather pay $200 for a lil more stock hp when in the end you amy as well end up changing the heads, cam, etc...


not the only option but my 2 cents... if you want instant power then go for the more output engine, but in the end i was gunna change the entire power assmebly so it really wasnt a factor...

 

I get what your saying. I mean if you plan on doing a build up then yeah dont worry about paying the extra $$ for the engine.

Well for right now the infamous 305 4 bolt is in. We have to clean the intake and runners and do the wiring and so foth yet.

I went to Advanced Auto last night to get a bushing for something and they did know what I was talking about and I need the tube for the TB and he didnt have any tubing sturdy enough to be bent from the manifold to the TB.

My step dad said the bushing is because of the newer and old engine and whatever it is wont bolt right on to the older 305......I forget what it is right now.

I think I have found a set of seats. I need to the peice of plastic that goes around the radio, center counsel lid, the plastic on top of the concle from the ash tray back.

I might get it on the road for a couple of months this year. Then maybe next year I will start looking into a 350 and I might just do a 350 build up....Not sure yet, I have plenty of time to think about it.

Plus next spring we will paint it.

 

Talked to my step dad last night he said we have a junk 350 from a blazer laying around.
He said he thinks the pistons are bad and probaly the rods.
So then I got to thinking well if I am going to do a rebuild why not go to a 383 and so I did a search and read some posts on 383 and did some searches for 383 kits and I found this.......

http://www.samperformance.com/Mercha...egory_Code=CSK

Looks good to me I mean a Cam, Crank pistons.
Oh and they say FOR AN ADDITIONAL $199.00 YOU CAN GET FORGED 5.7 "I" BEAM CONNECTING RODS FOR THIS KIT, OR "H" BEAM RODS FOR $385.00. WE CAN BALANCE THIS KIT FOR AN EXTRA $250.00

So for like $1000 I could get this kit.
I know I should probaly find a machine shop and ask them about boreing and so forth.

But does this sound like a good idea? I was even thinking of getting headers and cat back exhaust too.

I would have to look into suspenion stuff too....

A problem I do see though is the TPI, wiring and computer.

 

You can be sure the cam would not be TPI-friendly. To handle a 383, a TPI would require significant modifications. The kit doesn't include the needed external balance damper and flexplate.

Although a 383 would be nice, a 350 would probably be more practical if you're keeping TPI.

 

I hate to assume anything but for right now I am going to assume thats why they say
WE CAN BALANCE THIS KIT FOR AN EXTRA $250.00

Cause Powerhouse says
Balance (Includes Flexplate, Balancer, 1-Pc. Seal) (+$269.00)

PA just has visaul inspection for emissions.
I wonder if I could go with carb then.

 

You'd need to contact them to make sure they're supplying the balancer and flexplate when they balance it.

 

Deffintely will contact them before I do anything.

But they also have it on ebay and they say
THESE KITS CAN BE CUSTOMIZED TO FIT YOUR NEEDS, E-MAIL US & LET KNOW WHAT YOU NEED. WE HAVE SEVERAL DIFFERENT CAM GRINDS TO CHOOSE FROM
So I could get a different cam.

http://cgi.ebay.com/ebaymotors/SB-CH...QQcmdZViewItem

 

wat year was the blazer.. it was a K5 blazer riight... btw i believe the "balancing" is the rotating assmy and not a balancer/ flywheel


wat they are doing is matching rod weights and so forth

 

That's "weight matching", it's not the same as balancing. To balance it, they have to spin the crank with equivalent bob weights attached to the rod journals and measure for imbalance.

 

no wonder why it costs an arm and leg to get this stuff done.. thanks ape another bit of info saved for later use

 

Yeah it was a K5 77 I think.
I looked on ebay and a blancer is like 50 and a fly wheel is 30 so after shipping i think it comes to about $100. So thats not to bad. It will probaly be another year or so before I do anything.
Im just looking, studying and weighing my options.

 

I've picked up such parts on eBay, but they were the internally balanced kind. The external balance were more.

 

Hey Thanks for the info Five7. I'll keep that in mind.
The 305 should be done this weekend!!!