HELP!! LSx install in SBC chassis?

[jeff-texas]

BigAl1 said:

the Alt bulky bracket is bugging me! I'm considering designing my own that puts it down low LH side. The difference vs GM Camaro/Firebird setup is the belt path is closer to the block, so AFAIK the GM F-body bracket will not align the alternator pulley with the Corvette crank pulley. Maybe the GTO setup could work?

- I'm not familiar with the GTO's belt-pattern, but for brackets:
- check out M Koch's website for some ideas (pretty easy: just cut some scrap-alloy if you have large enough pieces left-over, but bend it so that it has strength like a C-beam or L-beam; i.e., an I-beam would literally be shaped like an "I" and these are just shaped differently for light-duty applications like an alt bracket. HomeDepot should also have some lightweight L-shaped steel.) -- which I think Mark revised and he shows why he revised it later in his diary.
- or use a turnbuckle,
- or the vintageair, hotrodair, Street & Performance, and many others can inspire ideas...
Some important things are that it's well-aligned with the other pulleys (using spacers) and STRONG so it won't flex as you apply belt tension (or else it's more likely to throw the belt or wear the rubber belt abnormally).

- But for one reason, I don't like the idea of putting an alternator down low: It's electrical, and although no one I know of takes their Ultima off-roading on purpose, roads do get flooded sometimes and even if the water's only 6" deep it can freeboard (swell to more than 6", since you and/or others are moving thru it)... :-) Some people find low mounting-locations worthwhile due to the lower Cg, but I'm planning to get my Cg lower by moving *non* electrical items lower, or at least keeping electrical stuff that's mounted low inside of the cockpit.
- If I understand, to emulate the GTO, you would just put the alternator down low, then put an idler above the pulley (i.e. where the pulley used to be mounted) so your belt clears the water-pump's pulley? If so, that sounds fine, so long as you don't mind the risk of getting your alt wet.

[jschwartz]

AL,
Use an Fbody alt bracket, (mounts it low and to the left). Machine the block side of that bracket to fit the shorter LS2 or corvette belt set-up.
Jeff S
www.schwartzperformance.com

[crafty]

Some photos

[mkoch1]

here are some pictures of the bracket I made up





mark

[steve_d]

That'll take some breaking.

Steve

[Boosted Ls1]

mkoch1 said:

here are some pictures of the bracket I made up [mark

Mark, why did you make the bracket when you could have used an F body alternator. Or is that a vette pulley and you didn't want a top mounted alt?

Boosted.

[mkoch1]

It is a vett motor, it had to be mounted low because of the electric water pump. I though about using the f-body mount but I needed a place to mount the crack trigger sensor so it was easier just to make one.

mark

[Boosted Ls1]

Thanks Mark.

Boosted.

[Barry Ashcroft]

Crafty looks awesome mate

[crafty]

Barry,

Thanks....pretty stoked with it myself... permanent smile at the moment. Started with the water hoses and fuel lines last night and realized I dont have enough Earls fittings.... haveing a bit of a splurge online today.

Yours is sweet.... was yours the car @ the Ultima open day??

[Barry Ashcroft]

Yep that was me, I built it with the intention of removing the engine for an Ultima Can-Am the comments from Ted about my car made the trip worthwhile that was it's initial shakedown run before it went to the states a fortnight later.

Where are you based? Where you there that day?

[crafty]

Barry Ashcroft said:

Where are you based? Where you there that day?

Im in Hong Kong, but I went to the open day to make a decision on colour. Saw your car, it was very a very nastly little piece of work...nice one!!

[crafty]

Al,

Back on topic..... did you get your mounts to work?

I have adaptor plates with SB mounts and I found that this makes the distance between the holes on the engine mounts too large(like from one side of the engine to the other - the "width" at the engine mounts if you like)

The engine is currently sitting in the chassis with one side lined up and the other side about 1" out on holes to the chassis.

I would have thought that the name "LS to SB adaptor plate" would have been a good description of its funtion, but the ones I have heard of used in Ultima's dont bolt directly in.

I notice Marck Koch had the same problem. He used solid mounts and elongated the holes towards the engine... narrowing the width between holes.

Scott did a similar thing with his LS7... he machined the back of the adaptor plates to bring them closer in ... and elongated the holes in the mounts.

Jeff Schwartz is running solid mounts by choice (he has ths LS chassis) and says they are not noticably harsh on ride, so that is one option.


How'd you go about it?

[Boosted Ls1]

What is the problem with the mounts? I produce a mounting bracket which bolts to the block as usual. It can mount vertically to a subframe like the vette and/ or in camaro mode it can allow the engine to move fore/aft by nearly an inch. Would that be any use?

Boosted.

[crafty]

Al,

Further developments on the weekend.

Jeff put a set of 3/4" spacers between the block and the idler/tensioner and another set of 3/4" spacers between the idler/tensioner and the AC unit. This spaced the AC 1.5 inches off the block, with the idler/tensioner still "mid span".

This setup made the AC clear the engine mounts... however the inlet/outlet on the AC was in front of the diagonal brace to the engine mount. I am spacing it off another 3" to clear everything.... getting new spacers machined today. Ill send some shots soon.

[BigAl1]

Hi All,
Thanks for all the replies on the thread. Just back from holidays, so hope to have some solid answers tomorrow evening regarding the adapter plates and the mounts working with the SBC chassis. The adapter plates with the 1" shift to the rear (motor is moved forward 1" fit up, and the A/C compressor will clear the mounts nicely. Still waiting for the LS2 Corvette water pump with the shorter pulley to take final measurments regarding the firewall clearance problem, but I *think* it will have +1/2" of clearance.
Something I noticed about the Prothane motor mounts I'm using is the tabs that extend down which get the bolt through and through the chassis pipe has a weld internally which will prevent the mount from sitting down on the chassis pad properly. This will hold the mounts up and prevent the bolt from aligning. I will grind the chassis pad zone to clear this weld. Also, I made sure to oversize the holes in the Prothane motor mounts to allow some adjustability during installation. The adapter plates I am making have the motor mount bolts welded in as studs since access to the back side of the plates to hold the bolt head is very tight.
For another option on the A/C compressor, the GTO version has the hose ports on the side. I'm going to stay with the Corvette alternator mount.
See www.ultimagtr.ca/march_2006/index.html for pics.

Allan

[crafty]

Al,

I'm keen to see if your engine mounts fit. Im thinking you may have the same problem I have... the distance from the hole where the bolt runs through the mount and the chassis > the block is where the problem is with mine.

I put on post on LS1tech and a guy responded:

"I ran into this problem with my Nova. I bought it without a drive train, so I had to scrounge up a lot of parts, motor mounts being one of them. The first set I used had the same alignment problem you are having so I went back to my shed and found another pair. The second pair lined up without any problem.
Why? The first set were from a 1966 Beaumont (Chevelle) and the second set were from another Nova. Somewhere between '66 and '71, GM made a slight change in the mounts. It's quite possible you have run into the same problem I did."


I havent got around to asking further questions....its impossible to get answers in Hong Kong. If yours dont fit, maybe you can check this out over there...

[steve_D]

Many before you have had to grind a chamfer on the (chassis) mount plate to clear weld on the inside of the engine mount and that is with an SBC.

Steve

[crafty]

Al,

It seems that this is a common problem with these mounts

www.ls1tech.com/forums/showthread.php?p=4451088#post4451088

[crafty]

There are 2 sizes of mount.

www.energysuspension.com/pages/univ2.html