V8Rumble

iTrader: (2)

I was looking around Summit's site the other day, & found a set of LSx swap motor mounts, & I'd like to get feedback from any or all of you as to whether you think they'd work or not. At first glance, I don't see any reason why they wouldn't...

The PN is TRD-4572, & the page contains the following:

and...

Considering the fact that they're less than $50 (or roughly half the cost of the others I knew about), if no-one here knows for sure, I might very well order them myself, & "be the guinea pig" for you guys...

GM-LSX

Fit?

To the Engine: Yes

To the Car: No

five7kid

iTrader: (14)

I guess I don't understand why they wouldn't fit the car.

82Five-O

I agree with five7. The mounts should fit any car or truck that has the mounts for a small or big block chevy, they're the same.

cam-

Price is right. The off set looks about right to me from memory. Give it a shot and post up. If they work good we'll update the sticky with that PN

bingo

iTrader: (2)

The plates look like a steel version of what Street & Performance has been selling for years. I don't see why they wouldn't work.

cam-

The S&P ones I looked at relocated the engine half of the stock third gen mounts with plates that bolted onto the LS1. These ones look to use the LS1 clamshells and relocate the mounts on the c member. Much better IMO. maybe S&P mounts are like that now I dont know whats current its been ages since I was looking for mounts thankfully

V8Rumble

iTrader: (2)

Hmmm. Looks like I might NOT be getting the mounts mentioned above - not after finding these...

Does anyone know if the LSx-series engines have enough room to take advantage of the 1" setback motor mounts, or would the engine run into the firewall/wiper motor/heater box/etc.??

(Being able to mount the engine a little closer to the center of the car would be very cool from a balance & handling perspective, but not if the hassles seriously outweigh the benefits - which I really suspect would be the case...)

Thanks guys!

cam-

Its pretty tight back there. Especially if you use the stock heater box then I seriously doubt you will be able to move it back. Keep in mind if you move the engine back you will need a new driveshaft too and have to shorten your torque arm or at least modify/relocate the mount. You might be able to squeak an inch without firewall mods but the LS1 wiring harness runs back there as well as a few sensors that will also need some tweaking to clear. Its doable but more grief than I think its worth. I've had no issues with the pan rubbing on the c member fwiw. Only downside is its a bit tight to get everything in from above and I am DREADING changing clutches. We'll see I suppose

V8Rumble

iTrader: (2)

Well, the driveshaft is a valid concern, but I have a BMR Trak-Pak torque arm sitting in my garage, so I'm already planning on relocating the front torque arm mount.

In all honesty, I don't think it'd be worth it on a street car, as there are other things that would be impacted as well - the A/C (if installed), possibly exhaust clearance, not to mention the fact that any kind of work that requires access at the back 1/3 (or so) of the engine would become that much more difficult...

It's a cool thought for a road-race car though!

five7kid

iTrader: (14)

I just ordered the Trans-Dapt parts from Summit. They're back-ordered to 1/21/08. We'll see when they get here, I probably won't be ready for them by then, anyway.

five7kid

iTrader: (14)

New expected arrival date - now 1/11/08.

five7kid

iTrader: (14)

The good news: The mounts have been delivered.

The bad news: I'm out of town.

V8Rumble

iTrader: (2)

Dang, that Murphy character is a bastage...

fenton06

five7kid

iTrader: (14)

Not sure if this is understood by all, but what they are is a plate that bolts on to the LSx engine. You then bolt your stock whatever mounts to the plates.

Now I have to find some new poly inserts for the stock mounts. Since I'll be pulling the front springs, I'll do the mounts while the a-arms are down.

89RsPower!

57 are you taking any pictures of your progress?

five7kid

iTrader: (14)

You've seen a picture of every bolt I've turned so far . . .

89RsPower!

haha, still in the parts aquisition phase or just need some free time?

five7kid

iTrader: (14)

Yes. . .

five7kid

iTrader: (14)

Okay, first issue - the stock 3rd gen passenger side mount bolts right where you need to notch the crossmember for the stock LS1 f-body AC compressor. The plate also hits the AC bracket, and the 3rd gen shell will hit the AC compressor itself.

So, if you keep the stock LS1 f-body AC compressor, you'll need to either notch the crossmember ( https://www.thirdgen.org/forums/ltx-...ompressor.html ) and use Hawks/Spohn conversion mounts, or use a Hawks/Spohn tubular LS1 crossmember.

If you want to use the Trans Dapt mounts, you'll either have to eliminate AC, or move the AC compressor (one approach: https://www.thirdgen.org/forums/ltx-...my-own-ac.html ).

Eliminating AC was getting attractive before (less fabrication/modification, less weight), it's looking even more so now.

V8Rumble

iTrader: (2)

Arrrrgghhh... In a small way, I feel responsible for your aggravation. Even though I had nothing to do with how they're made, if I hadn't posted this, you might've gotten the other mounts, & not had to deal with this particular issue...

Not to mention a LOT easier to work on the passenger side of the engine...

five7kid

iTrader: (14)

Don't worry, I take full responsibility for my actions. {I'm just darned glad I happened to start on the passenger side.}

I'm reconsidering the Hawks/Spohn mounts. I would like poly inserts, so it's the question of continuing on my present course with AC delete, or the somewhat arguably cleaner 4th gen mount system.

AC delete would also make it easier to mount the PCM in the passenger compartment.

cam-

Thats a bummer re the mounts. As for the poly I am VERY pleased I went with poly. Its not very harsh at all in fact its quite smooth and even with the poly I had some initial exhaust rubbage going on its pretty tight in more than a couple spots with these swaps and poly limits movement to practically nothing. I would imagine non poly mounts and the shaking around would have led me to much more aggravation in my case. I believe I bought prothane brand for 60 bucks or thereabouts.

five7kid

iTrader: (14)

The more I think about it, I think I'm going to return the T-D mounts and 3rd gen poly inserts to Summit and get 4th gen poly inserts, and get the LS1 swap mounts from Hawks/Spohn.

I asked my wife what she would think if the car didn't have AC - although she wasn't hard over one way or another, she was a good sounding board. The intend all along was for a quick, fun, full-creature-comforts car, so in keeping with the original objectives, that seems like the way to go.

One notched k-member coming up. . .

motenkjr

iTrader: (1)

Sorry to bring up this old thread but if I weren't to have AC would this work for my swap? The mounts from summit that is....

five7kid

iTrader: (14)

Yes.

motenkjr

iTrader: (1)

And this is all that's needed? I don't mean to sound like a retard...I don't know if it makes a difference that I'm using a 5.3 or not.

1ADan

iTrader: (4)

yes, these plates are all you would need to use your factory mounts on the newer gen 3/4 motors (4.8, 5.3, 5.7, 6.0, etc). however, i would opt for a set that is noted as 1" setback to get the bellhousing and trans in the same position as the facrory sbc. gives a bit more room between the kmember and the oil pan. grabbed my set off ebay for under $40.

five7kid

iTrader: (14)

Personally, I would not opt for the 1" setback. The clearance between an f-body oil pan and the K-member isn't improved that much, and putting the engine back that close to the firewall creates other issues. I still had to notch the K-member with the setback, and I liked having the extra space between the back of the heads and the firewall without the setback.

To each his own, but that's my opinion.

DerrenZ

I agree with five7 on this. And use the term "extra" loosely. For me there was just enough space to get the job done back there, I don't think it would have been possible with one inch less.

As it is, I had to remove some from my heater box. The wiring harness is very busy at the back, and especially snug when I reinstalled my wiper motor.

Stevo

iTrader: (45)

Ok maybe i'm not understanding this. The hawks/spohn mounts are not setback?

I thought the only difference is one allows you to reuse the sbc mounts while the other uses ls1 mounts.

If using ebay 1" setback plates will a spohn trans member still work?

1ADan

iTrader: (4)

pocket and i did measurements with the two styles; the spohn/hawk mounts put the motor in the same spot as the 1" setback adapters, which should both put the trans in the same spot as the original sbc setup

xpndbl3

iTrader: (5)

1" setback is "stock" bellhousing location for a gen 1 motor. So it would be in the same place as factory for the trans and driveshaft locations.

motenkjr

iTrader: (1)

Y'all lost me lol. I think I'll just stick with the hawks/poly mounts. Cause all I'll nerd then is those two things and it'll all line up correctly, right?

Stevo

iTrader: (45)

Ok makes sense. Why is Five saying the clearance is different then?

1ADan

iTrader: (4)

not sure. every car's got its little differences, but if you check out our posts #70 & 71 here, i measured 1" further forward with the non-setback plates than pocket. when i swapped the 5.3 out for the 6.0, i bought setbacks and got the same spacing as pocket.

Stevo

iTrader: (45)

I know it will be close either way. I plan on using setback plates because i already have brand new poly sbc mounts.