1,600 pounds and LS power!! Brunton M-spec

[subtlez28]

I've been getting a bit done. I'll try to catch the thread up some.

On the oil pressure adaptor I decided to spend the money for the nice engineering and machining of the Katech piece. The part that was on there site actually would not clear an LS3 intake. However, after emailing them I found out they had just produced a new part to clear the LS3 intake w no grinding needed. It was a more costly, but the machining was clearly more intensive. I just really want to keep the build as simple, OEM, and uncluttered as possible. So an OEM sending unit hidden under the intake worked for me. I intend to use "Can-bus" gauges. These use signals from the factory sending units via the OBDII diagnostic port (more on that later).

The Katech piece is machined beautifully and is sealed via O-ring!





Sorry, the cell phone pics really do not do it justice.

I also got the steering shaft installed which gave me the opportunity to sit in the car, turn the wheel and make engine noises! It is starting to become a car.


I took the engine off the stand and installed the LS7 flywheel with OEM bolts that came w the kit.


Put on Brunton's engine stands:


I also bolted up the LS1 F-body bell housing and CTS-V trans. I forgot to get action shots of it in the air, but I was able to swing the whole unit into place with the chassis still up on the stands!



Next I installed the new CTS rear center section (3.23 gears and G30 limited slip):


And measured for the drive shaft:


I'm working through details, but I am told I should remove the flange from the trans, and go to a slip yoke. More on that to come.


BTW, I am currently searching for a stock first gen CTS-V shifter assembly and trans mount to try. I'm coming up empty and would appreciate any help in tracking them down for a reasonable price!

[subtlez28]

I'm working to get all the major components on hand. I am pre-assembling pretty much everything. With the engine in I could get a feel for how much wiring harness I would need.



I called up Speartech and spoke w John. After a lot of research I feel comfortable he will provide a harness what will be cleanly built to fit my simplistic (subtle) style, and have the know how to help me through any potential bump in the process. I am especially fond of his testing every harness on a real engine set up prior to ship out!

Now the hard part, waiting for them to get through there back log of orders so they can build mine! I probably couldn't have picked a worse time of year to order, but I really wanted the engine/trans in before pulling the trigger.

Gratuitous engine pics (that I don't think are in the thread yet):

[meenaggie]

Cheater bar was one of the legs off our engine hoist. They are usually removable for easy storage. Yeah, I think you could get enough torque using that to strip just about anything. Looks like a fun project.

[andrewb70]

Shaun,

What kind of flange is on the diff? I would explore a few options before replacing the bolt in yoke with a slip yoke. How is the trans aligned with the rear end? Are they basically inline?

Andrew

[R32Jordie]

Great Build Shaun, Would love to undertake a project like this at some point. You cant go wrong with big engine small car :D

My question is did you choose the CTS diff or was that part of the M-spec kit? I just know there has been some issues with CTS Diffs howling and whining. GM rectified this problem in 2006 with a beefier differential.

[subtlez28]

Cheater bar was one of the legs off our engine hoist. They are usually removable for easy storage. Yeah, I think you could get enough torque using that to strip just about anything. Looks like a fun project.

Correct on all counts!

Shaun,

What kind of flange is on the diff? I would explore a few options before replacing the bolt in yoke with a slip yoke. How is the trans aligned with the rear end? Are they basically inline?

Andrew

Odd three bolt flange. I was also leaning toward making the flange work, but am getting differing advise from Brunton. I may contact the company I purchased my Jeep Rubicon drive shaft from. Rubicons do not have slip yokes. The drive shaft itself has a slip section. I think the issue is the CTS-V flange is odd, so an adaptor ($$!) is needed. The Jeeps for instance run a 4 bolt flange.

The trans and diff do appear to be in line, though I am struggling to get accurate measurements. I can adjust driveline angle via motor and trans mounts. The diff is in a fixed position.

Great Build Shaun, Would love to undertake a project like this at some point. You cant go wrong with big engine small car :D

My question is did you choose the CTS diff or was that part of the M-spec kit? I just know there has been some issues with CTS Diffs howling and whining. GM rectified this problem in 2006 with a beefier differential.

Thanks. The diff is not included but the chassis is set up for it. I know about the CTS-Vs ruining these diffs, but keep in mind, this car weighs way less than 1/2 what a Caddy does. Also, the new unit I have has a stamping right on it from Getreg saying "Noise test - OK". My hope is the new diffs are up to the task.

[andrewb70]

Correct on all counts!



Odd three bolt flange. I was also leaning toward making the flange work, but am getting differing advise from Brunton. I may contact the company I purchased my Jeep Rubicon drive shaft from. Rubicons do not have slip yokes. The drive shaft itself has a slip section. I think the issue is the CTS-V flange is odd, so an adaptor ($$!) is needed. The Jeeps for instance run a 4 bolt flange.

The trans and diff do appear to be in line, though I am struggling to get accurate measurements. I can adjust driveline angle via motor and trans mounts. The diff is in a fixed position.



Thanks. The diff is not included but the chassis is set up for it. I know about the CTS-Vs ruining these diffs, but keep in mind, this car weighs way less than 1/2 what a Caddy does. Also, the new unit I have has a stamping right on it from Getreg saying "Noise test - OK". My hope is the new diffs are up to the task.

Shaun,

I wouldn't use the off-road style telescoping style driveshaft on a road car. You really need a good driveshaft that will operate smoothly at high speeds. I would give Frank a call at The Driveshaft Shop. Since you are running a CTSV trans and rear end, you would just need a shorter version of his aluminum shaft that he sells for CTSVs.

http://www.driveshaftshop.com/domest...hafts/cadillac

The CV joint in the front will basically eliminate any concerns about driveline angles and will also have some travel for any trans and diff movements.

Andrew

[subtlez28]

Shaun,

I wouldn't use the off-road style telescoping style driveshaft on a road car. You really need a good driveshaft that will operate smoothly at high speeds. I would give Frank a call at The Driveshaft Shop. Since you are running a CTSV trans and rear end, you would just need a shorter version of his aluminum shaft that he sells for CTSVs.

http://www.driveshaftshop.com/domest...hafts/cadillac

The CV joint in the front will basically eliminate any concerns about driveline angles and will also have some travel for any trans and diff movements.

Andrew

Thanks for the input Andrew.

I questioned wether a telescoping shaft would be able to deal w the RPMs this will face.

I shot off an email to the company you linked. I'm sure they are nice pieces, but the cost of the ones linked is a bit scary. I see they also offer the conversion blocks to change from the 3 bolt to the more typical 4. However, at $149 each (times 2) that isn't necessarily cheaper...

I also shot off an email to Tom Woods. We'll see what I find out. I'm told conversion to a slip yoke is as straight forward as unbolting the flange, and cutting off the alignment dowel. What I read on sources reference converting CTS-V T-56s to F-body style, I was put off by the complexity and cost. But then, maybe most others also sought to convert to the F-bpdy rear shift position. In all honesty doing that would solve two problems for me. I'll check into that option also.

[andrewb70]

Thanks for the input Andrew.

I questioned wether a telescoping shaft would be able to deal w the RPMs this will face.

I shot off an email to the company you linked. I'm sure they are nice pieces, but the cost of the ones linked is a bit scary. I see they also offer the conversion blocks to change from the 3 bolt to the more typical 4. However, at $149 each (times 2) that isn't necessarily cheaper...

I also shot off an email to Tom Woods. We'll see what I find out. I'm told conversion to a slip yoke is as straight forward as unbolting the flange, and cutting off the alignment dowel. What I read on sources reference converting CTS-V T-56s to F-body style, I was put off by the complexity and cost. But then, maybe most others also sought to convert to the F-bpdy rear shift position. In all honesty doing that would solve two problems for me. I'll check into that option also.

Frank is terrible about returning emails. I would pick up the phone and call him. He is usually pretty accessible by phone. The other guy that answers the phone(I forget his name) is very knowledgable as well.

I fear that you don't have an inexpensive solution. I think that the splines on the output shaft of the CTSV trans are not very long and are not suitable for a regular slip yoke.

$900 bucks for a driveshaft with the adapters and CV joint isn't too bad. Here is a more "scary" piece...

http://www.markwilliams.com/detail.aspx?ID=1855

Andrew

[subtlez28]

Frank is terrible about returning emails. I would pick up the phone and call him. He is usually pretty accessible by phone. The other guy that answers the phone(I forget his name) is very knowledgable as well.

I fear that you don't have an inexpensive solution. I think that the splines on the output shaft of the CTSV trans are not very long and are not suitable for a regular slip yoke.

$900 bucks for a driveshaft with the adapters and CV joint isn't too bad. Here is a more "scary" piece...

http://www.markwilliams.com/detail.aspx?ID=1855

Andrew

I have not pulled the flange yet, but I was thinking about your spline engagement point. I guess the existing splines hold the fixed flange, and the slip yoke will not actually do any slipping once installed (IRS), so that should be ok, right?

If I remove the flange, per Brunton's recommendation, they will send me a drive shaft (that I paid for with the kit). So, that is the most $ friendly alternative.

[andrewb70]

I have not pulled the flange yet, but I was thinking about your spline engagement point. I guess the existing splines hold the fixed flange, and the slip yoke will not actually do any slipping once installed (IRS), so that should be ok, right?

If I remove the flange, per Brunton's recommendation, they will send me a drive shaft (that I paid for with the kit). So, that is the most $ friendly alternative.

The slip yoke will move some, but very little. I would say less than 1/16". If Brunton has already tested this, I would go with it. As you said, it is the least expensive solution. What do they do for the diff end of the driveshaft?

Andrew

[R32Jordie]

Thanks. The diff is not included but the chassis is set up for it. I know about the CTS-Vs ruining these diffs, but keep in mind, this car weighs way less than 1/2 what a Caddy does. Also, the new unit I have has a stamping right on it from Getreg saying "Noise test - OK". My hope is the new diffs are up to the task.

Good to know that it has passed the noise test haha. I figured you wouldn't be putting to much stress on it because of the weight of the car. Just thought id mention it because i just watched as my co-worker just had his replaced at the stealership for a pretty penny. Keep up the good work.

[Motown 454]

Nice project!

[Tig]

This is very cool.
Awesome job.






subd

[subtlez28]

Nice project!

This is very cool.
Awesome job.
subd

Thanks guys!

After banging my head against the wall trying to locate the stock CTS-V shifter parts, I started actively shopping for a GTO or F-body style T-56. While speaking with a trans shop who specializes in Tremecs, I was discussing converting my CTS-V trans to a GTO tailhousing, and main shaft. Bad news is the GTO main shaft is nationally back-ordered... As a stroke of luck though, the guy had a stock CTS-V shifter set up!! I may still convert to the GTO tail housing down the road if I don't love the remote shifter, but at least this will get me going!

I also located a company making a stronger CTS-V trans mount. Apparently the stocker is weak, and failure prone. They also make some shifter bushings I hope will firm up the Caddy shifter.

Beyond finding parts I also got some garage time in. A friend who has been a huge help and motivator committed some hours over the weekend. We got the floor mounted Wilwood brake and clutch pedal mounted. We initially tried to mount them a little further toward the back of the car thinking it would provide more foot room, as the footwell narrows. But when I began to modify the firewall and hang the brake booster and master it was clear I had to move the pedals forward. It was basically a lot of time put in for minimal visible result, but, I'm glad to have progress toward a driving car!



The clutch pedal has a master mounted to it. Brunton makes a bracket for the Miata power booster mounting it backward and above the fire wall as the engine takes up the room where a brake MC and booster would typically go. They also provide a lever system that converts your forward brake pedal motion to backward. Space is at a premium in such a small chassis! Part of me would really like to try manual brakes, but the advise of experienced Stalker owners is to keep power brakes.

I also installed a front rotor and caliper. I took out my Percy's Wheelrite tool to make some measurements at full travel. Another area of my research lately is into track wheel/tire set up. A lot of Lotus 7 replica's run 13" race wheels. With the Wilwoods, that is a tight fit, requiring pricey custom wheels. After a discussion w a race tire distributer I was shied away from 14", 16", and 17". He explained (used) race tires are much easier to come by in 13, 15, and 18" sizes. I don't mean to come across as too cheap, but my budget is running thin, and I want to be able to afford to finish and race this beast, this year! Anyway, I am looking at probably going with a 15x10 custom steel wheel from a manufacturer who just so happens to be right here in WI! Think oval track wheels. Obviously a 15x10 steel wheel is not the lightest option, but w sticky tires, I don't think it will hold me back as much as my weigh OCD would have me think... Plus, I could always pony up for some lightweight custom alloy wheels in a year or two if I still want to.



And, yes, I know I should remove the plastic from the rotor and paper tag from the caliper prior to high speed use. LOL

[andrewb70]

Shaun,

Why are you scared of running manual brakes? I have a 4000 pound car and I run manual brakes. For a racing tip application, you can't beat the ability to modulate the brakes like a manual set-up gives.

Andrew

[subtlez28]

Shaun,

Why are you scared of running manual brakes? I have a 4000 pound car and I run manual brakes. For a racing tip application, you can't beat the ability to modulate the brakes like a manual set-up gives.

Andrew

I was actually thinking this would be an ideal car to have manual brakes. However, the guys at Brunton are adamant that power is the way to go. They ran manual brakes on their personal cars, but now have switched to power. They swear it is the better set up and specifically state that manual brakes at high speed required s lot of pedal pressure, which complicated heel/toe downshifting.

The power set up was included with the kit. And now I have it installed, so I guess I will run it. I brought up the simplicity, and feel counterpoint when I was speccing out the car, but I figure you need to listen to experience sometimes. I have no reason to doubt them.

[subtlez28]

Over the summer months I have made some progress. Pace has slowed to a crawl due to the increased activities of summer and my kids being home during the day, but that is far from a complaint.

When I have worked on the car it has been in short bursts, and I have neglected to take pics, which I know takes some of the fun out of the thread. We fit the seats, harnesses, pedals, and all the aluminum. We mounted the engine and took measurements needed for harness and driveshaft.

My use of the CTS-V style trans required some creativity for shifter mounting. Unlike F-body (Camaro/Firebird) style T-56s that mount the shifter right on the tail-housing of the trans, the CTS-V shifter is remote mounted, but with solid linkage.


The bad news, is with linkage at stock length, the shifter position is right were a chassis tube was (already removed in the pic). In a car Brunton built, they cut down the linkage to fit more like an F-body trans. We decided to move the chassis tube and create a mounting point to support the shifter.


The goal from the start was to trial fit most of the components, then take it apart to have the chassis powder coated. We got to that point, and I found a reasonable local powder coater. I'm proud to say I tore the car down to bare chassis in a mater of less than two hours! I was pretty excited to reach this milestone!


One week later:


We already have the front suspension back in place, and bent up some brake lines. Soon we will plumb the fuel system. I put in another nearly $1k order to Summit for car electric harness and fuel system parts, fittings etc. I think I can see light at the end of this tunnel!

[andrewb70]

Great progress Shaun and great hanging out with you the other day!

Andrew

[Motorcitydak]

This is one hell of a build and a sweet car! Glad you posted it here! Really looking forward to more progress