Thread: Frankenstein Engine Swap

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So the title may be a bit more flashy than the actual situation. I have a 69 Chevy truck that previously had (i think original) a 307, which i pulled. It now has a 305 out of a Camaro. I'm working on an ever decreasing budget, so a crate motor wasn't in the cards. My dilemma is that I am not upgrading much more than the intake, carb, and clutch (not really an upgrade but more so a newer clutch for the motor to mate with the 69 3 spd trans). The headers off the 69 307 fit the 305 heads decently, no clearance issues other than only being able to thread 5 of 6 bolts on passenger side of motor. Needless to say, this is my first engine swap and I'm finding myself undereducated and in need of some advice. Any help will be greatly appreciated!

Welcome to CHR. I expect if you post specific questions there will be someone here who can either offer guidance based on experience, or general guidance that will get you moving to the next step. Pictures get you bonus points......

Why will the 6th bolt not thread in? Describe the headers....shorty or long tube....what primary tube diameter....what is the flange thickness?
What intake manifold is on the 305? What manifold is the upgrade?
What carburetor is on the 305? What carburetor is the upgrade?
Why do you feel the need to change the carb and intake?
Have you monitored the fuel pressure at the bowl inlet? No modern 4-bbl will tolerate much more than about 5 psi. Pressures over that will overpower the needle and seat and allow the fuel pump to blow raw fuel into the intake manifold, creating a tuning nightmare. Is that what's going on?

Trust me on this....you're going to need to open up and talk about what's going on. We love helping others with their problems, but we are not mind readers.

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I expect the bolt pattern is slightly off. A rat tail file might be the ticket.

"..... I expect if you post specific questions there will be someone here who can either offer guidance based on experience, or general guidance that will get you moving to the next step......"

".......Trust me on this....you're going to need to open up and talk about what's going on. We love helping others with their problems, but we are not mind readers......"

X3

There is a lot of hands on engine swap experience on the site and I doubt that you are running into something that someone here hasn't seen before..........we just need to know what you are running into.

It will be helpful to start off with letting us know what year the 305 you're working with is. Not all of the 305s are the same. 1986 was the first year for the 1 piece rear crank seal and these engines use a different flywheel (different bolt circle on the mounting flange and counter-weighted) than the flywheel that is on the 307 you're taking out. If the 305 has center bolt heads (valve cover bolts in center of the cover instead of 4 bolts on the perimeter) the intakes from the 307 or other earlier small blocks will not interchange due to different angle the manifold bolts go in.

Basically this should be a pull the old engine and install the new one.......any issues should be easy to overcome with the right parts, but we need to know what those issues are.



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Originally Posted by techinspector1

Why will the 6th bolt not thread in? Describe the headers....shorty or long tube....what primary tube diameter....what is the flange thickness?
What intake manifold is on the 305? What manifold is the upgrade?
What carburetor is on the 305? What carburetor is the upgrade?
Why do you feel the need to change the carb and intake?
Have you monitored the fuel pressure at the bowl inlet? No modern 4-bbl will tolerate much more than about 5 psi. Pressures over that will overpower the needle and seat and allow the fuel pump to blow raw fuel into the intake manifold, creating a tuning nightmare. Is that what's going on?

Trust me on this....you're going to need to open up and talk about what's going on. We love helping others with their problems, but we are not mind readers.

.

i managed to get the 6th bolt to thread in, had to remvoe the header and slip the bolt in and will now thread into the head. the 305 didn't come with an intake or carb so i bought an Edelbrock Performer #2104 and a Edelbrock 4bbl carb #1406. I'm also going to use an Edelbrock adapter for the carb #2696.

Originally Posted by Mike P

"..... I expect if you post specific questions there will be someone here who can either offer guidance based on experience, or general guidance that will get you moving to the next step......"

".......Trust me on this....you're going to need to open up and talk about what's going on. We love helping others with their problems, but we are not mind readers......"

X3

There is a lot of hands on engine swap experience on the site and I doubt that you are running into something that someone here hasn't seen before..........we just need to know what you are running into.

It will be helpful to start off with letting us know what year the 305 you're working with is. Not all of the 305s are the same. 1986 was the first year for the 1 piece rear crank seal and these engines use a different flywheel (different bolt circle on the mounting flange and counter-weighted) than the flywheel that is on the 307 you're taking out. If the 305 has center bolt heads (valve cover bolts in center of the cover instead of 4 bolts on the perimeter) the intakes from the 307 or other earlier small blocks will not interchange due to different angle the manifold bolts go in.

Basically this should be a pull the old engine and install the new one.......any issues should be easy to overcome with the right parts, but we need to know what those issues are.



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the 305 is out of a 92 Camaro. i found out through attempting to transfer parts from the 307 to the 305 that they are quite different. so i purchased a new flywheel, intake and a carb for the 305. and a gentleman at advanced auto (non employee) that i would need a clutch kit for a 67 Chevelle in order to use the 1969 3spd trans with the newer motor.

so you bought a combo that with a Edelbrock carb you need an adapter to put it on an Edelbrock manifold??

the block off plate for the choke seems to be getting in the way, so i figured the adapter would help with the clearance issue

image.jpgimage.jpgimage.jpg

I don't know why they are sideways but here are some reference photos

Yup - you will need the adaptor as the 1406 is a square carb and your manifold is designed for spread bore (Q-Jet, OEM) carbs. This will also take care of your clearance issue with the EGR port.

If you have not already done so, down load these four instruction sheets:

http://www.edelbrock.com/automotive/.../2000/2104.pdf

http://www.edelbrock.com/automotive/.../2000/2696.pdf

http://www.edelbrock.com/automotive/.../8000/8031.pdf

http://www.edelbrock.com/automotive/...406_manual.pdf

In all likelihood, you will need to re-jet and change the metering rods on the 1406. They're known for running a bit rich and it will be a dog on the 305 at low RPM. if that's the case, look on page 22 and 23 of the 1406 manual and go with reference number 7 - 1426 (.095) Main Jet and 1456 (073 x 047) Metering Rod. Replace the carb gasket too - Edelbrock part number 1472. Fairly straight forward to do, but a couple tiny parts can be easily lost so if you've never done this one, take the carb off the engine and perform the work on your bench over a nice clean white rag.

Let us know how she goes,
Glenn

Glenn, thank you so much. this is my first engine swap and i am getting a bit down on myself about it. so it means a lot to have not only you, but everyone else here to seek advice and suggestions from. making this a lot easier.

why didn't you buy the manifold for the square base carb????? instead of spread bore manifold/square carb???

couldn't find one for the '92 305. right now I'm trying to locate a clutch return spring for the throwout bearing. I've tried multiple sites ( jegs, summit, lmc, classictruck, etc.) so I'm going to try the hardware store. but if anyone has suggestions please let me know.

Originally Posted by bigred69

couldn't find one for the '92 305. right now I'm trying to locate a clutch return spring for the throwout bearing. I've tried multiple sites ( jegs, summit, lmc, classictruck, etc.) so I'm going to try the hardware store. but if anyone has suggestions please let me know.

LMC Truck, '67-72 Pickups, Page 144 Lower Right - $3.95 plus the ride, must be cut to length and bent with a hook - Truck Parts and Truck Accessories They've got just about anything OEM for your truck, and they're great people to work with, right here in Lenexa, KS, western KC metro area.