350 v8 swap possible issues/required parts?

[ryanthomas1]

Okay fellow Datsun fans. I need some get up in go in this truck so its getting a 350 so hush about it, its happening, and no, I will not sell my z22 engine. Now that that's out of the way my questions are the following. My truck is a 720 1982, z22 carb, extended cab, 2pc driveshaft, automatic trans

 

 

1. Is there any fitment issues for a 350/th350 trans? Radiator/ trans reaching driveshaft in long tail , overdrive, or standard casting trans. Will I have to cut holes in my firewall?

 

2. Will I have to modify my driveshaft or running gear to get this to work?

 

3. To just use the 350's mechanical fuel pump do I work around the multiple filters and only use one for the system? or is it okay to have multiple for the pump to work through ? ( I've had otherwise good filters slow up a system before.)

 

4. What am I looking to do with motor mounts?

 

 

I appreciate all the helpful answers, just trying to smooth this swap along, its my daily driver, so when I pick the week off to do this, I would love correct crucial parts.

 

[flatcat19]

Want to just give me the Z22 then?

[datzenmike]

Okay fellow Datsun fans. I need some get up in go in this truck so its getting a 350 so hush about it, its happening, and no, I will not sell my z22 engine. Now that that's out of the way my questions are the following. My truck is a 720 1982, z22 carb, extended cab, 2pc driveshaft, automatic trans

 

 

1. Is there any fitment issues for a 350/th350 trans? Radiator/ trans reaching driveshaft in long tail , overdrive, or standard casting trans. Will I have to cut holes in my firewall?

A SBC won't fit in a 620, too long, don't know about the 720, I think they are larger?. Measure the distance from the back of the engine to the front of the fan. Now see if it fits the 720 bay and will clear the rad. If not then rad in the box or cut the firewall and take the heater out.

 

2. Will I have to modify my driveshaft or running gear to get this to work?

 

Almost certainly the driveshaft will need a different spline and length for the TH350. The H190 is 7.5" diameter and strong enough if you don't add too much traction (super wide tires) and do all day burn outs. 

 

3. To just use the 350's mechanical fuel pump do I work around the multiple filters and only use one for the system? or is it okay to have multiple for the pump to work through ? ( I've had otherwise good filters slow up a system before.)

 

Do what ever chev does. If no filter before the mechanical pump fine, but always before the carb.

 

4. What am I looking to do with motor mounts?

 

 Well this is an uncommon swap and not well documented. Lots of custom one off parts like oil pan, exhaust, MM's, trans mounts, rad, driveshaft.

[Lockleaf]

It's pretty uncommon on here to see a finished v8 720, so there won't be many easy answers coming your way.

 

1. Yeah almost guaranteed you're going to need to cut the firewall to clear the trans. Pretty likely the tunnel is too small. Possibly you can work around this by installing a body lift instead.

 

Other issues, use the short nose water pump and matching pulleys. Help you get as much clearance as possible. May not be able to run mechanical fan due to space. Your radiator is now too small to efficiently cool the engine. They also make small cap distributors. Using one will allow you to get closer to the firewall, but you may have to dent it out cut it out there as well.

 

2. Yes you will need a custom driveshaft. I'm sure the lengths are different but also Nissan shaft won't slip in/on to a Chevy trans.

 

3. Just install a nice inline filter before the carb just like Chevy did.

 

4. You are looking to build them on your own. Or you can gamble, since both 720 and D21 ran z engines, and also since a D21 ka24 will bolt right in to a 720, you can buy a set of d21 v8 swap mounts and hope they fit. Or transdapt Toyota 80s v8 mounts seem like they will fit with a minimum of modification.

 

Take tons of pics, document everything, post it all here.

[Dolomite]

Glws

[Mr.Dean_Yates]

If your engine bay is anything like mine was, I'd say drop a v6 in it, less cutting and what not. At least that's how I see it. Could be wrong haha. Good luck though man I'll be keeping my eye on out for it

[Boxcar]

 Yes a smc will fit in a 620 or a 720 , even the 510........  It's been done thousands of times.

Yes it will require a complete re design of the rig. Fire wall , frame mods , cooling mods , drive line , trans tunnel , suspension etc.

Not a job for the fabrication and or engineering challenged builder........... The end results usually leave a bit to be desired......

[DISLEXICDIME]

There where a couple guys at Canby with ls1 720's

[datzenmike]

 Yes a smc will fit in a 620 or a 720 , even the 510........  It's been done thousands of times.

Yes it will require a complete re design of the rig. Fire wall , frame mods , cooling mods , drive line , trans tunnel , suspension etc.

Not a job for the fabrication and or engineering challenged builder........... The end results usually leave a bit to be desired......

 

Hasn't been done thousands of times. A couple dozen maybe. The other 976 were scrapped.

[DrvnDrvr]

Putting a 250HP+/- motor in a truck that was designed for a 100HP motor and something's gonna break.

A truck is only as strong as it's weakest part....

That project is gonna be a lot of work.

It is what it is.

Chevy put a V8 305 in a Monza sometime in the 80's and there's precious few of those around now.

Do what you want but IMHO I'd rather drive my truck than work on it.

The V6 option sounds like a more workable option.

Best of luck

[Boxcar]

 Your just to young to remember them all Mike....Small block swaps were all the rage in the 70's and 80's.

I did more than a few myself.

 

 Terrible driving rigs. 600 lb chunk of iron sleeved under the front of  small car or truck just doesn't pencil out.

 

Now if you are lucky enough to find an early 60's Buick or Oldsmobile 215  aluminum block v8 the fit is good , the weight is right but the hp can be matched or bettered with a KA.

The only real advantage is the sound... Hard to beat the sound of a well tuned V8.

 

 Remember this one?

 

Or this one.

 

 

Then there is the uber nuts Roadster conversion.

 

[datzenmike]

Love the sound of a pushrod V8! Mostly Vegas and pinto swaps I recall. Few Falcons and Chevy II 's.... more room and they fit.

[DISLEXICDIME]

Just use a 250 horse 4 cylinder

[datzenmike]

Lets see one idle at the lights for 20 seconds or start reliably at 34 degrees or stop and go driving in Seattle.

[DISLEXICDIME]

Lets see one idle at the lights for 20 seconds or start reliably at 34 degrees or stop and go driving in Seattle.

A 250 hp 4 cylinder?

[datzenmike]

yes.

 

I would rather have a stock 4 cylinder. When they get that high they are a race engine and a bit temperamental and high strung.

[mhub91]

Glws

 

lol. 

 

best post yet.

[Farmer Joe]

Lets see one idle at the lights for 20 seconds or start reliably at 34 degrees or stop and go driving in Seattle.

 

you must not know what an SR20det is. or a ca18det.. 

 

rorys 300horse CA18 starts up no problem in the winter. drives just fine too. tuned fuel injection is a pretty cool thing. you might wanna look into it. 

 

 

but i digress. 

 

 

to the OP, have fun with your swap.

[datzenmike]

Forgot about EFI. Was thinking smaller and carbed.

[mhub91]

SBC, LS and all other V8's have a time and a place -- a huge place, a cross all other chassis, but I feel that Datsuns aren't a suitable chassis for a V8.

 

Sure, people do them but what's more impressive? Cutting up a hard-to-find Japanese classic car to stuff in an overly-credited V8 in? Or having a VG, KA, SR, CA, or Frankensteined LZ engine placed in there?

 

My opinion? build a smaller 4 cyl or 6 cyl Nissan! Just my .02