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Discussion Starter #1
1985 305 350 California Engine Swap

Questions at end.

Goal:Good dependability and smogable.
The guy at Jegs says the engine below will drop right in.
The CA Smog Referee says do it and re-install the smog stuff. He said treat it as a "replacement" engine.

NEW
Jegs 350 Engine Components Package 1 #809-10067353K1
EGR intake ($40 more)
Hei dist, wires, coil
260hp
$2,320 delivered to my California door.
Harmonic Balancer
water pump
knock sensor
180 thermostat

RE-USE
brackets, compressor, smog pump and all smog crap, power stearing pump
not so old 3 row radiator
radiator fan and not so old fan clutch
starter
flexplate
E4ME Quadrajet CCC carb
CA legal with O2 sensor headers
th200 trans - future swap project

QUESTIONS
6.75" or 8" balancer?
Will old starter and flexplate bolt on?
Will the CCC E4ME carb work without rejetting?
How about clearance for hood to close? On the old 305 I put a Holly Street Dominator and it fit under the hood no problem. Is the 350 taller? Will it require a "low rise" manifold?

thank you very much, Zoomer56
 

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The basic engines have been the same since 1955. If your starter is old, a new Power Master starter is a good idea. It's lighter than a stock starter also. The 8" balancer would be my choice, with a timing tab to match.
Flex plate depends on if both engines are the same rear seal and crank configuration, like a late engine has circular one-piece rear oil seal, whereas the earlier engines have a two piece seal, which means a different crank flange, where the flex plate has to match.
 

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Discussion Starter #3
...snip... The 8" balancer would be my choice, with a timing tab to match.
Flex plate depends on if both engines are the same rear seal and crank configuration, like a late engine has circular one-piece rear oil seal, whereas the earlier engines have a two piece seal, which means a different crank flange, where the flex plate has to match.
sb, thanks for the reply - The Jegs motor must not be a "late" model. It is advertised as a 1973-1985 motor with a 2-piece rear main seal.

Good, so I will proceed with 3 questions answered and use the same strtr n flex and get an 8" balancer.

Without further advice and words I have seen elsewhere I will proceed with the stock Quadrajet Carb and see what happens.

MORE QUESTIONS
Still need advice about fitting this in. I do not want to change the hood.
What about the distributor? I need to research to see if a particular type is needed with the ECM and CCC smog stuff.

thank you, Zoomer56
 

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If you still have the ECM (computer) and running that electronic carb, you will need the distributor that goes with it, the electronic advance. (no vacuum canister) You could use the old one, or trade it in on an exchange rebuilt one, which may be a good idea if it has high miles on it.
Hood clearance is a non-issue. The new engine is the same physical dimensions as the old one.
Of course you have to remove the hood for the engine change. If you mark the locations of the bolt heads on the hood before you remove it, it's easier to get it back on and lined up etc.
 

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My Dad built a 383 stroker for his '87, and we have emissions here in Az. Running Edelbrock TES headers, Edelbrock performer manifold, Comp cam, Hooker cat back exhaust, '87 Monte SS ECM, stock distributor, and all the California emissions hooked up. No tweaks to the carb was needed, and still gets 20mpg. All this fits under the stock hood, a real sleeper Elcamino! This swap can be done.
 

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You'll definitely need to keep the original distributor. Otherwise the knock sensor won't be able to function properly. If you change the balancer, you'll probably need to install a timing tab and determine TDC or 0 degrees. The stock 305 balancer is read at 12:00 high, any balancer change will probably not line up with the 12 o'clock reading.
 

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Discussion Starter #7
steelybill said:
If you still have the ECM (computer) and running that electronic carb, you will need the distributor that goes with it, ...snip... Hood clearance is a non-issue. ...snip...
Awesome! Things are falling in place. The ECM is still here and I will use the old distributor . . . maybe will look for a rebuilt one.

[quote-jrodgto] ... snip... we have emissions here in Az.
Edelbrock TES headers
Edelbrock performer manifold
Comp cam
Hooker cat back exhaust
'87 Monte SS ECM
stock distributor
California emissions hooked up
No tweaks to the carb
gets 20mpg.
All this fits under the stock hood, a real sleeper Elcamino! This swap can be done.
[/quote]

JrodGTO Excellent info, exactly what I was hoping to hear.

...snip...keep the original distributor. Otherwise the knock sensor won't [work]. If you change the balancer, you'll probably need to install a timing tab and determine TDC or 0 degrees. The stock 305 balancer is read at 12:00 high, any balancer change will probably not line up with the 12 o'clock reading.
Rix, I have decided to go with the 8" (have not measured the 305 one) because it will be new. The Jegs documentation says it has tab for 6.75" and 8" balancer. Bigger must be better right. Ah yes, I understand the knock sensor will generate a voltage which will then be used to alter the distributor advance . . . I will keep the distributor. When its time to start things up I will try to ensure TDC, distrubutor position and timing mark are all correct. 12:00 high . . . I will ensure the 8" balancer from Jegs is applicable to their 8" tab. 20mpg . . . I like it, very acceptable!

Some more web crawling for specific parts and I think I will be able to order this Monday.

thank you for the insight and succcess stories,
I will be passing on my own succes story in about a month,
Zoomer56
 

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About the carburetor: The Quadrajet simply adds fuel to the air going through it. It does not know if it is feeding a 350 at 1000 rpm or a 305 at 1100 rpm. It only sees a given amount of pressure drop over the venturis in the carb and the fuel flows accordingly. If it had a mass air flow sensor or a throttle position sensor, the computer could wonder why there was ore air flow at a given PRM point, but you don't have that problem.

Since this is a system that will keep going through the California smog tests, you'll need to keep the system intact. The only thing that cn be non operational is the early fuel evap valve in the right hand exhaust manifold.. Since your car will always be smogged warm, they'll neve know if it works or not. So, if the butterfly has rusted and fallen off, don't worry about it. The computer metered QJ's do their best to keep the mixture correct throughout the air flow range and I think you'll find that it will do the job as well on the 350 as the 305. On the earlier (non computer) QJs, you might have wanted to go one or two jet sizes bigger on the primaries, but you can't do that on the computer carbs because the computer will just keep the metering rods buried deeper to make up for it.
 

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Discussion Starter #10
About the carburetor: The Quadrajet ... adds fuel to the air going through it. It does not know if it is feeding a 350 at 1000 rpm or a 305 at 1100 rpm. ...snip...

Kerno, that makes good sense.

...snip... [for] California smog tests, you'll need to keep the system intact. ...snip...

Yes, and I see from yourwords below and other words I have read that the QJ will do the job.

The computer metered QJ's do their best to keep the mixture correct throughout the air flow range and I think you'll find that it will do the job as well on the 350 as the 305....snip
More from me as I buy, await delivery and start the swap.
thank you, Zoomer56
 

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Discussion Starter #11
Time to give back. I have started the 305 350 California swap. Not done yet but have copious pics and some lessons already learned. Do you have a suggestion on a way for me to cronicle the transformation.
 

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Start your own thread like Mike P. and steelybill, take lots of pics. and describe your work as you go.
Go back to post #8 and check out steelybill's photo thread.
 

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I am certain someone will correct me if I am wrong, and I'll agree with all the other info you have so far, but as far as the Harmonic Balancer, I do beleive you'll need to get a new one for the 350. The 350 and 305 are balanced differantly. One is internal balanced one is external balanced, so it would seem to me, you need to get the correct balancer for that engine, and as already suggested, be sure to get the correct timing tab. Best of Luck, should be a smooth swap.
 

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I'm going out on a limb here by saying that a 305 and a 350 are both internally balanced. A 383 may or may not be, a 396 is internal, but a 400 is external. A 427 is internal and a 454 is external. Are you confused yet?

I've never seen any significant horsepower or engine life to be gained by going to a large balancer. The car may be faster, but only because your wallet is lighter.
 

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well,consiriding its a baisc, and not Enhanced,I 'm sure your'e in the clear with that new engine.In a Basic Area you may obtain your inspection at any licensed Smog Check station. You will receive the same Two-Speed Idle test you have always received. Your vehicle will be tested for harmful levels of emissions of hydrocarbons and carbon monoxide. Your vehicle must be tested every two years, when sold, or upon initial California registration. :beer:
 

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I'm going out on a limb here by saying that a 305 and a 350 are both internally balanced. A 383 may or may not be, a 396 is internal, but a 400 is external. A 427 is internal and a 454 is external. Are you confused yet?

I've never seen any significant horsepower or engine life to be gained by going to a large balancer. The car may be faster, but only because your wallet is lighter.
You may be correct Kerno, and why I said to be corrected if i am wrong. Its my understanding that 305 and 350 have the same stroke and same cranks, and even share the same cast # sometimes, but are not interchangeable cranks due to balancing methods and there is supposed to be a way to tell a 305 crank from a 350 crank.
 

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You may be correct Kerno, and why I said to be corrected if i am wrong. Its my understanding that 305 and 350 have the same stroke and same cranks, and even share the same cast # sometimes, but are not interchangeable cranks due to balancing methods and there is supposed to be a way to tell a 305 crank from a 350 crank.
And on your note of a 396 vs 400, you are reffering to Big Blocks, where the big block 400 is actually a 402 and GM refers to it as a 400, BUT, not to be confused with a Small Block 400 since they are 2 totally differant animals altogether. Right, again, a bigger balancer will NOT increase torque or horsepower in anyway shape or form. I'd just go with whichever balancer is going to have the correct TDC locator for the timing tab, and have my engine within factory balance spec unless I had my engine balanced.
 

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Awesome idea zzomer. I see you scan notes, save diagrams photo's and all in your photobucket. I save all the same stuff but I do it in folder on my hdd that I back up frequently so I don't lose it. As cheap as digital cams are these days, there is no reason not to take pics of before an after. You never know when you have to go back on a before pic to see how something WAS before you took it apart, since a night of sleep and a 12 pack, you tend to forget what you had before. :nanawrench:
 
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