SheldonZ28

iTrader: (1)

Hey Everyone.

Ive got my other thread directed to exhaust ,but it sorta trailed off, and let me to other questions.

Heres my setup:

S&P Style mounts
4L60e From a '95 Camaro (Same dimentions as a 700R4)

When mounting the setup, it moves my transmission 1" Forward. This means i loose 1" of the driveshaft sliding onto the tailshaft, and it means the back of my motor is 1" further forward then it would be if it was stock. The tailshaft currently has 1 3/8" distance that goes into the driveshaft

Between the back of my oil pan & my k-member ive got 11 1/4" of room. With my truck pan that means ive got lots of clearance, with an f-body pan that mean's ive got 1/4" - 3/8" of interference.

Ive got no problem cleaning up my k-member a little, or at the most extreme, doing a minor knotch. What i do have an issue with, is too little tailshaft - driveshaft yolk interference, and the driveshaft flying off the end at launch or when the suspension unloads

Im aware i need a convertor pilot spacer, thats not an issue, im just working out spacing issues right now. If i need to get a body mount torque arm, thats not an issue either.

Heres a shot of my modified k-member to allow the mount to move forward 1"



And a shot of the distance between the back of my motor and firewall



Im just looking for some re-assurance that these mounts will work out in my car. Im trying to get around having to buy LS1 mounts then making up my own horseshoe brackets. Ive spent less then $1500 getting this far (motor, tranny, f-body accessories, intake etc) and im aiming to keep it that way.

Thanks!

cam-

Hmmm I am a tad baffled by this. My LS1 engine sits further back than stock and I have very very little drive shaft yoke slip left. It might be because my car is so slammed but my oil pan is so tight to the cross member I cant even slide a piece of cradboard between the k member and the pan.

What has me slightly puzzled here is yours is 1" forward... I think I;d get the f body pan on there first before modding anything to fit

SheldonZ28

iTrader: (1)

Thanks for your help cam!

According to a thread on LS1tech, between the back of the pan and the front of the part where it sits lower, is 11.5" so that means i should have approximately 1/4" of interference. Which seems odd.

Ill be getting a f-body pan this week while im in florida.

do you think 1.5" of interference between the driveshaft and tailshaft is alright?

I guess the worst that happens is i find some LS1 clamshell mounts and make up the horseshoe bracket.

88 350 tpi formula

iTrader: (9)

I had this issue. it's the adapter plates you are using as you have figured out.. make the eng. sit too far forward. (as you also know people have gotten them to work by notching and welding)


I went with the spohn ls1 mounts and the factory ls1 camaro mounts. I figured after all the work the spohn mounts were the way to go. I have a picture or two of those installed to give you an idea on what way you want to go..

good luck with the swap..

cam-

1.5" seems light to me. It will probably be okay if you dont pound on it but even still it would eat on my mind while I was driving. If the mounts drop it in the wrong spot just bolt them all together, unbolt the mounts from the k-member, place it where you want it, mark the mounts on the k-member and then drill new holes after. Bolt it all up and presto your good to go

SheldonZ28

iTrader: (1)

Thanks for your help guy's!

I think im just going to bite the bullet and buy some LS1 motor mounts to save me having to knotch my k-member.

Im a pretty good welder,so fabricating the horseshoe mount should be no issue.

Just a quick question for cam & anyone using spohn mounts, would the length of the peice that sticks up to accept the mount, be the same size as the stock mount?

If someone could get me an approximate hole center to mount plate distance, that would be awesome!

Thanks so much for your help guy's, this broke 17 year old needs it!

cam-

Making the mounts was easy. I made the horseshoe and bolted them onto the LS1 mounts. I made the plate and bolted it to the car. I dropped the engine down and positioned it where i wanted it then tacked the horeshoes onto the plates. Removed the mounts and welded them up proper.

I still think you could make those other mounts work if you relocate the bottom half on the k-member

SheldonZ28

iTrader: (1)

I think that if i knotch the k-member about 1/2" across the bottom i should be ok. Hell, if i got a tubular k-member ,id definately be good, but thats a little out of the budget.

Im not sure whether its ok for me to just notch my k-member and move on with the same mounts, or make the horseshoe mounts.

The main worry is the tailshaft/driveshaft. The next issue would be exhaust, do those stainless works headers really have room for them to be 1" further forward? Id like to put them on my car eventually, but if their going to hit off something, it may be easiest for me to just change my mount setup at this point.

SheldonZ28

iTrader: (1)

Bit the bullet, think im going to grab the LS1 style mounts for $40 shipped to me.

The tail shaft slip length really makes me nervous, so im thinking ill try these out. If i figure out a way to make the other mounts work, maybe i can machine out a bunch of them and sell em

cam-

Good price. I paid $40.00 plus shipping.

Still... I dont know if your following me here. You could easily just move the mount location on the k-member and use the S&P ones. Its only a few holes to drill no biggie.

SheldonZ28

iTrader: (1)

oh! Now i see what your saying!

Just as quick as i posted on LS1tech that i wanted mounts, the offer dropped on my lap and i took it.

Im going to try drilling the k-member to move the mount and see how well it works. If it works ok, i can just re-sell my mounts.

Thanks cam!

1987earthquake

iTrader: (5)

Hey Sheldon I didn't realize you were on here too. One thing I thought about was possibly flipping the plates to where it then puts the engine back further but not sure on how much clearance it would leave for the drive shaft maybe try that and see before drilling your k-member. it it sets it too far back I would drill the k-member. no sense in spending money you don't have to spend... Let me know what you come up with.

SheldonZ28

iTrader: (1)

The way the plates are now, they actually have the motor sitting as far back as possible with that plate style. Not movement of the plate will have the motor move back.

That being said, i bought the LS1 Clamshell mounts and ill be making up a strap to bend around and make up my own Spohn style mounts. Ill see how that works, and pick which one i like best.

I checked rad hose sizes last night, and the '00 T/a Upper hose is a perfect fit, as is the lower hose, so i intend on using those with my stock rad.

My PS pump is the F-body PS pump with the truck feed line, and a thirdgen return line. The truck feed line is a bit long, but it fits alright, so ill use it. Thirdgen return line is a perfect fit.

Im not too happy with the wiring harness right now, as it runs all over the place and locates things in weird places. Ill work into that later.

Im gone on vacation next week. When i get home, im diving in headfirst to get this puppy running!

3.1EyeCandy

iTrader: (3)

Glad you got some progress. We just pulled my L98 this last weekend and I'm sourcing parts to fit the 700r4 up (as well as wiring). Keep us updated!

racer J

Actually, S&P has two different LS-1 motor mount plates. Do you know which one you have? I ask because, they make one that is longer and it will move the engine back 1".

Scroll to the bottom of the page (PDF format)

InfernalVortex

iTrader: (4)

I thought you couldnt use an LT1 transmission with an LS1? I know an LS1 T56 wont fit an LT1/Gen I block without some adapters and spacers and such...

If you get a 4l60e from an LS1 car I think you can reuse the stock driveshaft.

Im not super well-versed on these things, but from what I know about T56's and 700r4s, I'm sure you can make the LT1 4l60e work, but you'll probably have to use the same spacers and adapters that you're supposed to use to make an LS1 T56 work on a Gen I/II block. Or maybe I've got that backwards and you'd have to use negative spacers... which obviously dont exist.

Im not sure the problem is the mounts as much as it is the transmission, because from what I understand, with the swap mounts and the LS1 transmission, the driveshaft length is the same.

SheldonZ28

iTrader: (1)

In all honesty, ive got no knowledge towards mounting an LT1 T-56, however, i am aware of the 4L60e deal.

To mount my 4L60e, i needed to get a pilot spacer (Made by Hughes transmissions, dont have PN on hand), & a flat flywheel. My motor already had the flat flywheel, so i tapped my spacer in & that aspect was done. Then, since the LS1 has a 12" convertor and the LT1 uses a 11.5" convertor,the holes need to be ovalized inwards slightly so the convertor will bolt up. You will loose 1 mounting hole for the transmission, as the LT1 doesnt use the top of the bell housing bolt, but has 2 ones below the peak, where the LS1 has a bolt at the bellhousing top, but only one a bit further down on the sides.

Mounting plate wise. I milled out another set of S&P with the 1" of further length. However, it would reqire some block clearancing to get all the bolts in, so i figured i wouldnt bother. Ive got 2 sets of the non off-set S&P style mounts i made, and 1 offset style. I may offer them FS at some point. Their made of 6061 Grade aluminum, which i know is sufficient to hold a 400lb motor, because it is being more compressed then outright holding strength.

I bought a set of LS1 clamshell mounts, that im plannin on using to make some mounts that are similar to the Spohn ones, and will allow me to position things exactly as i like.

Ill update as i go along, i had planned on getting some work done this weekend, but will be visiting some family up north. Hopefully that will give me some time to get more wiring diagrams worked out.

Sheldon