H190 from 620 into B310

[K Wagon]

Hey guys.. new here. I am in the process of K-swapping my B310 wagon, and I need to upgrade the differential to handle the torque. I've read on here about swapping a h190 from a 620 and using the original side gears for the axles.. I called my friend who has a 1981 620 and he says he thinks I need special tools to do such a job. Is this true? and if so, where do I get these tools?

[datzenmike]

'81? if the year is correct it's a 720. Does it have rectangular headlights? It's a 720.

 

Forget the 620 and the 720. Your H-150 side gears won't fit it and neither will your axles. You are stuck with 6 lug rims and the gears are way too low for a KA swap. 

 

Get the axle out of a 510 wagon. It should fit better width wise* and is H-190 and 4 lug rims.

 

Other H-190 and 4 lug rim options are...

 

The 810 wagon. It's  an inch wider per side.

The '81-'84 Maxima wagon is even wider at 2".

The '82-'83 S110 200sx maybe 1 1/2" wider per side

The '84 S12 200sx is maybe 1 1/2" wider per side

 

*I could only compare wheel tread measurements and not the actual WMS (wheel mounting surfaces) where the rim touches the brake drum. Most Datsuns are zero off set but you would have to measure accurately and see. Wheel tread in the 210 is 51.2" the actual WMS may be more or less.

 

 

 

[K Wagon]

My friend just has a 720, I can purchase a rear end from a 620.. but if I can't swap side gears then I guess I'll look for different rear ends

[K Wagon]

47 minutes ago, datzenmike said:

Forget the 620 and the 720. Your H-150 side gears won't fit it and neither will your axles.

 

I'm positive I saw a comment from you saying someone could swap a H-190 from a 620 into a B310.. but maybe it was a H145 and not a H150

[datzenmike]

You could but nothing on the B-310 (210) axle will fit it. The 620 axle would still have 6 lug rims. The axle could be drilled for 4 lug and maybe the 510/810 maxima wagon drums would fit or the S110/S12 drums? The 620 drums are 10" I don't know what the cars are, otherwise drill the drums for 4 lug. It could be done.

 

The most common differential for the 620 is 4.375... a little revvy for the larger KA. A 3.70 would work better I think.

 

 

[K Wagon]

This is true. Although K series love to rev high - VTEC baby. 

 

My transmission im using does have an overdrive too.

 

Is the axle on the 620 just a bolt off, bolt on? Or do I have to custom fab connection points to the chassis?

[datzenmike]

25 minutes ago, K Wagon said:

 

 

My transmission im using does have an overdrive too.

 

Is the axle on the 620 just a bolt off, bolt on? Or do I have to custom fab connection points to the chassis?

 

If you are thinking of the 210 transmission... it won't fit the KA and it wouldn't last if it did.

 

The 620 uses a leaf spring on each side so 4 mounting points. Your 210 uses coil springs and four link to locate the axle on the car. I guess you could cut all the link and spring mounts off the 210 and weld onto the 620 axle... a lot of geometry to get right.

 

The '82-'83 S110 200sx and the '84 S12 both had coil spring and link rear axles. See my list. So these are a lot closer

 

 

[K Wagon]

I'm using a miata 5 speed, should be fine for the power I'm using

 

I have some time to look for the sx and s12 rear axles.. any ideas where to look? They are rare

[datzenmike]

You must have an adapter plate to mate Miata to KA???? Why not get a 2wd D21 Hardbody KA 5 speed???? Easier, more than strong enough and cheaper.

[K Wagon]

I'm using a K20z3, honda motor. There is an adapter plate for the motor to the miata transmission 

[datzenmike]

Gotcha. I know of it.

[K Wagon]

Okay so just to end this thread topic Mike, I cannot put my b310 side gears and axles into a 620 rear axle, I have to look for other rear axles

[datzenmike]

34 minutes ago, K Wagon said:

Okay so just to end this thread topic Mike, I cannot put my b310 side gears and axles into a 620 rear axle,

No, they will not fit.

 

 

34 minutes ago, K Wagon said:

I have to look for other rear axles

 

Yes.

[K Wagon]

I'll probably just go with an 8.8 from a crown vic and modify the links.

 

Thanks for your help

[datzenmike]

You need to measure the wms to wms distance. Mustang may be closer? Has to be close to the 210 for width. The 8.8 is likely 5 lug rim so what you going to do about that? Is the Viky coil or leaf spring? A lot more discovery is needed for this.

[K Wagon]

New rims and tires for the back. Viky is coil spring 😄

[datzenmike]

How wide?

 

Five lug?

 

 

[K Wagon]

5 lug, 65 inches