350 small block swap question

[Ralph Cassidy]

Hey everybody!

Wanted a few other opinions on something. Working on the tj 350 swap right now and wanted to ask is there anything I should do right now while the engine bay is this open and accessible? I'm already cleaning everything to look as showroom as possible, derusting the frame and then laying down chassis saver on everything from axles to frame to control arms etc. I just want a second set of eyes sort of to see if I'm missing anything important (i.e control arm bushing, suspension something , and anything else) while I have this much room to work before the engine goes in. Any help is greatly appreciated as always and thank you all in advance for the help! Just wanna make sure I'm not missing anything.

Thanks again!
Ralph

 

[Wildman]

I'd cut your exhaust off since it's right there and easy to get at. I'd cut it after the bend so once you get your Y pipe done you can hook it up if you're keeping the stock exhaust.

What Chevy 350 are you swapping in? What transmission?

 

[TJ4Jim]

If your retaining the stock suspension then I would replace the control arms with similar stock arms as the bushings are all 20 plus years old and you have good access to cut them out if necessary. Replacing the bushings on stock arms is not worth the effort.

 

[Ralph Cassidy]

Hey Wildman, I'm planning on running headers and am hoping to get an exhaust done alittle later on. Wanna hear open headers for alittle just for the fun of it ya know? Do you think any of the old pipe can be salvaged for the new system?

I'm swapping in a Gen 1 small block chevy 350. Its a crate motor from 1991 with a few aftermarket parts on it. Trans is going to be an ax15 thanks to the AA bellhousing that allows it all to bolt up. Just gotta get the ax15 from AA once I have a few more paychecks under my belt lol

 

[Ralph Cassidy]

If your retaining the stock suspension then I would replace the control arms with similar stock arms as the bushings are all 20 plus years old and you have good access to cut them out if necessary. Replacing the bushings on stock arms is not worth the effort.

That's a good point thank you. I didn't know if I needed to do control arms even though I'm pretty sure I should. I have a 3 inch lift in the front and 3.5 springs in the rear and all on stock control arms and bushings. Think its time for an upgrade?

 

[Wildman]

I wouldn't keep the stock exhaust system but I know people who have with a Dodge Magnum 5.2 & 1 5.9 swap.

IMO you need a 2.5" exhaust as a minimum for a 5.7 (350). I see you plan to run a carburetor also. I have to ask WHY? If you don't wheel your Jeep I guess it'll be okay but if you wheel it IMO I'd never go back to a carb over EFI.

And not to preach but your engine swap is technically illegal by federal EPA laws. Why not look for a used AX15 to get it running and then save for a the AA one.

That's a good point thank you. I didn't know if I needed to do control arms even though I'm pretty sure I should. I have a 3 inch lift in the front and 3.5 springs in the rear and all on stock control arms and bushings. Think its time for an upgrade?

If you still have stock control arms front and back and they are the original ones then yes I'd replace all of them. I'd buy a set of aftermarket arms that are adjustable.

Also are you going to run the stock Dana 35 rear axle? Done anything to beef it up?
I know a few guys who kept their Dana 35 after doing a V-8 swap but were saving for new rear axle.

 

[Ralph Cassidy]

I wouldn't keep the stock exhaust system but I know people who have with a Dodge Magnum 5.2 & 1 5.9 swap.

IMO you need a 2.5" exhaust as a minimum for a 5.7 (350). I see you plan to run a carburetor also. I have to ask WHY? If you don't wheel your Jeep I guess it'll be okay but if you wheel it IMO I'd never go back to a carb over EFI.

And not to preach but your engine swap is technically illegal by federal EPA laws. Why not look for a used AX15 to get it running and then save for a the AA one.



If you still have stock control arms front and back and they are the original ones then yes I'd replace all of them. I'd buy a set of aftermarket arms that are adjustable.

Also are you going to run the stock Dana 35 rear axle? Done anything to beef it up?
I know a few guys who kept their Dana 35 after doing a V-8 swap but were saving for new rear axle.

Ok that's what I figured also I wasn't going to keep the stock exhaust anything. I was also thinking 2.5 minimum so that's good to know.

So I'm carbureted for now because that's what the engine had on it when I bought it and I don't have the means to swap an EFI right now. I also wanted the experience running one as its my first carb on a car engine so I wanted it also as a learning experience. I do wheel my jeep very lightly for camping "overlanding" and some technical trails. Nothing crazy since the north east here has really nothing serious I'm learning. So a daily driver and camp vehicle will be it and I'm hoping it'll be alright. If not ill cross that bridge I suppose. Wait, what do you mean its technically illegal? My research had shown being its a "classic vehicle" id be alright in emissions speak in Connecticut. Looks like ill have to make a few calls tomorrow.

For my area the AX15 from junkyard with other 100k miles are only a few hundred from a brand new one from AA. new (refurbished) rebuilt, all that. And I already tried a junkie with an AX5 when I was running the 4 banger and it was giving a few issues toward the end. Not even a year old. So I figured it was best just to wait alittle longer and go big.

Good to know on the control arms side too. Do you have any recommendations on adjustable control arms? I haven't been able to nail down a set I was comfortable with and I've been looking for a while.

So, my Dana 35 has 4.88 gears I put in earlier this year so I will need to make a change very soon yes. Thinking I'd wait for a 8.8 or a junk Dana 35 with a lower numerical gear set in it to get me on the road again and sell mine with the 4.88's in em. I spoke with someone locally who did my swap and they're still running their Dana 35 without any issue so idk I haven't quite figured that out just yet.

 

[Wildman]

Okay that makes sense on the carburetor if you've never ran one before. Don't expect good MPG with it though. If it's an Edelbrock carb they offer some off-road parts for it that can help with things like fuel slosh. I'm old enough that I started on carbs & points in the distributor...... I hated EFI when it was first released but swear by it now.

I said you were technically illegal by Federal laws. By federal law you cannot swap an older engine into a new vehicle. And when swapping the same year or newer engine you are required to maintain all the emissions equipment from the model year of the engine.

Engine Switching Fact Sheet (epa.gov)

Engine Switching Fact Sheet: Off-Road.com (off-road.com)

There are a lot of different arms available. Currie or Savvy are considered some of the BEST available. Core 4X4 makes different level of arms that are reasonably priced.

Yes you can run the Dana 35 and it will survive for a while but if you get onto it with the added power you have available it can break. What size tires are running? Why would you change the Dana 35 for another one? The 4.88 gears should be ok with your V-8. I am running 5.13 gears in my TJ with a V-8 & 35" tires.

If your crate engine is basically a stock engine then 2.5" exhaust will be fine. If it has been hopped up you might need a 3" exahaust instead.
I'm building a stroked 5.9 (360) into a 6.7 (408) and plan on running a 3" exhaust for it.