Aftermarket Motor Mounts Not Needed For My RB25/S13 Swap.

[Boardman]

RB25 into '89 240sx using R33 crossmember and RB25 engine brackets/mounts + rotated trans mount

2 problems: The RB25 sits high and forward in the engine bay.So what to do?

I modified the OEM RB25 motor mounts- cut them in half, removed an inch of height, and re-welded them back together....one problem solved.I simply drilled new motor mount holes in the crossmember an inch towards the firewall. Two problems solved.

Engine doesn't hit the hood, no steering shaft/02 housing contact, oilpan clears swaybar, shifter is perfectly centered in shifter hole, plenty of clearance between radiator for an electric fan and clearance at the firewall.

It wasn't all that big a deal

(my cars been done for awhile now....just noticed an explosion of "motor mount" topics....thought I'd share)
Modified by Boardman at 3:09 AM 9/7/2004

[NISMO_RB25]

pics?

[Boardman]

This isn't rocket science.

[NISMO_RB25]

i know, but showing picks of it will give everyone an idea of how everything looks, and clears.

[TheOne]

looks easier to just get mckinney mounts.....no need to weld or anything,lol.

[DSMs_Suck]

Looks alot cheaper than mounts from McKinney tho

Good idea man, but I agree that pics would definately be nice to see. How much do you think cutting the mounts DROPPED the engine?

Murray

[Boardman]

If people say you can use the stock mounts but need to trim the skeleton of the hood partially....I simply removed one inch from the middle section of the RB mounts using a sawzall/cutting wheel/grinding...then welded it all back up.Problem solved.

If people say the motor sits forward with stock crossmember and the shifter sits an inch forward in the hole etc etc....I just drilled another two holes (per side) one inch away from the stock crossmember holes towards the firewall.Problem solved.

I knew I wanted to modify/fabricate instead of spending money/waiting for mounts...I gave it alot of thought solving the fitment issue while the swap was in progress.....what I came up with even surprised myself when it came out perfect and wasn't any trouble at all.

I'm not saying mounts suck blah blah blah....Mack at McKinney is a great guy+ runs a good business...I'm just giving my testimonial on what I did, that is all.

[xjon]

I think that's great that you got to do it that way Boardman. Too bad I didn't have the RB mounts to begin with and also the time to bring them to the shop. That would have saved me a few hundred. Hopefully, you sharing this info will save a bunch of people a few hundred.

[Wulfgang]

Unless your welds are better than flawless, I think they will eventually fail in that position. You will notice that Nissan does not support the engine at all by the weld itself -- the weld just keeps the mount together. The weight of the engine is supported by a half-roll in the steel on the engine side and by folded steel on the x-member side. On the OEM mount, if all of the welds were to fail, the mount would still hold the engine up.

[Boardman]

^Makes no sense.

[Equinox]

I know that the McKinney kit comes with the driveshaft and transmission mount. Boardman, what did you use for these items?

[TheOne]

i think he means it'll make the crossmember weaker after sometime compared to using mckinney(or other) mounts because you have welded over something thats solid(somwhat).

thats why when you crash a car and they gotta weld it or so to fix it, it'll cost less when ya sell it, cause it gets weaker than when it wasn't crashed.

[DSMs_Suck]

Don't mckinney's mounts rely on the weld holding the true weight of the motor?

[Wulfgang]

Sorry that didn't make sense. Where did those pics go that Cameron took of the OEM mounts??? Did someone axe that sticky?

Anyway, on my RB20 mounts, you can easily see that the mount will keep holding the engine up even if all of the welds completely crack. After seeing the design, I decided against making up my own mounts. Not a good thing when your engine falls onto the x-member.

But maybe you'll never have any problems with them. Also, I haven't seen McKinney mounts up close. I have only heard of cracking with homemade mount solutions.

[Boardman]

Mount means the roundish metal/rubber piece with one bolt coming through the top and two bolts on the bottom.

Let's say for the sake of argument- the mount is 7 inches long from bolt to bolt.I cut the mount in half...removed 1 inch of material. And welded it back together.The mount is now 6 inches long bolt to bolt. Still connects on the top to the OEM engine bracket- and connects on the bottom to the OEM crossmember.
Modified by Boardman at 1:44 PM 9/9/2004

[Boardman]

I used a stock KA trans mount flipped around- no mods necessary except a couple 10cent "spacers".

The custom 1-piece driveshaft i had made at http://www.shafts.com which is local to me....1 day-service About $350- worth every penny.

The parts they used:part number________description________________quantity3103-30_________Nissan 4x4 Hardbody Slip Yoke______13102-21_________1310/Nissan Conversion Flange______1N2-28-437________1310 3 x .083 Tube Yokes_________21-0153___________1310 Series Joint________________2N24-30-42-108_______3 x .083 Tubing______________3.5

The metal on the crossmember where the new holes are, are double-thick steel, no weakness by not welding up the old holes.

number 1 is the engine to mount bracket (never modified).number 2 is the engine mount....i made the cut and removed an inch where the white line is.
Modified by Boardman at 2:04 PM 9/9/2004

[Wulfgang]

Ah, ok. You cut the rubber itself.... looks like that should work. I thought you meant the "bracket." RB20 setup is a bit different too. The brackets are welded, not cast.

Good luck with the rest of your swap.

[Boardman]

thanks, it's been done for awhile.can't wait until the next one:)