Katech Dual-Threat Street/Track Build

[Nick S]

Originally Posted by Katech_Zach

Small update, the block has been clearanced for the 4" stroke. I will begin assembling the heads today. I made an update to the rotating assembly, so I am now waiting on a different set of rods and a crank. I chose to go with a crank and rod combination that utilized a 2.000" rod journal instead of the standard 2.100".

Can I ask the reason why you decided to go with a smaller than standard journal bearing diameter? Just trying to learn why the decisions were made.

Thanks.

[cdb95z28]

Zach, did you make any headway on the LSR bumpsteer kit?

[SS Performance]

Interested in who's piston squirters you are using.

[Katech_Zach]

Originally Posted by Nick S

Can I ask the reason why you decided to go with a smaller than standard journal bearing diameter? Just trying to learn why the decisions were made.

Thanks.

Nick, there are many pros and cons to different sized bearing journals. Without getting extremely technical, the reason why I chose a slightly smaller one for my personal project is the following:

1) Decreased bearing surface speed relative to RPM.
2) Less mass

Mass change is negligible. It may be a difference of 1.5lbs.
The decreased surface speed and friction is the more desired characteristic.

Originally Posted by cdb95z28

Zach, did you make any headway on the LSR bumpsteer kit?

I have the pieces close to being done, I have not had the time to tap them. I recreated the body using 4340 instead of 6061 aluminum. All I have to do is tap them followed by powdercoating. I will post more on this when they are finished.

Originally Posted by SS Performance

Interested in who's piston squirters you are using.

I will be using our Katech Piston Squirter designed for 4" strokes. The OEM LS9 squirters will not clear a 4" stroke.

https://store.katechengines.com/kate...irter-p74.aspx

[Nick S]

Originally Posted by Katech_Zach

Nick, there are many pros and cons to different sized bearing journals. Without getting extremely technical, the reason why I chose a slightly smaller one for my personal project is the following:

1) Decreased bearing surface speed relative to RPM.
2) Less mass

Mass change is negligible. It may be a difference of 1.5lbs.
The decreased surface speed and friction is the more desired characteristic.



I have the pieces close to being done, I have not had the time to tap them. I recreated the body using 4340 instead of 6061 aluminum. All I have to do is tap them followed by powdercoating. I will post more on this when they are finished.



I will be using our Katech Piston Squirter designed for 4" strokes. The OEM LS9 squirters will not clear a 4" stroke.

https://store.katechengines.com/kate...irter-p74.aspx

Hi Zach,
Ok the decreased bearing surface velocity makes sense. Initially I was just thinking that smaller diameter journals would mean less shear strength due to a smaller cross sectional area. But I can definitely understand the bearing surface speed if you are looking to get more RPMs out of the engine.

Thanks for sharing your thought process and reasoning. It definitely helps to understand all the factors going into the build!

[Katech_Zach]

Originally Posted by Nick S

Hi Zach,
Ok the decreased bearing surface velocity makes sense. Initially I was just thinking that smaller diameter journals would mean less shear strength due to a smaller cross sectional area. But I can definitely understand the bearing surface speed if you are looking to get more RPMs out of the engine.

Thanks for sharing your thought process and reasoning. It definitely helps to understand all the factors going into the build!

This is true, the crankshaft is "weaker" as far as sheer strength goes when comparing the same crank with and without a smaller diameter rod journal. For the power levels that I am targeting, I will not have to worry.

[Katech_Zach]

Update over the weekend: Heads are fully blueprinted and assembled. There are 6 angles on the intake and 4 angles on the exhaust for this valve job. My cam choice ended up working out perfectly as far as installed heights went. After the heads were assembled, I installed the CHE bronze trunion kit into my new OEM GM 1.7 rocker arms. Lastly, took my GMPP CTS-VR lifters and threw them in an oil bath. They will sit in there until they are ready to go into the engine.

Bonus picture includes the headers that arrived from Grams Performance. They are a 1-3/4" to 1-7/8" stepped header. Quality looks great, now I just have to see if they make power like the Kooks signature series did.

[Nick S]

Looking good Zach.

I did have a question for you about the engine build in general. How much different is your 416 LS3 build compared to the "off the shelf" 416 LS3 that Katech already offers?

Thanks.

[Katech_Zach]

Originally Posted by Nick S

Looking good Zach.

I did have a question for you about the engine build in general. How much different is your 416 LS3 build compared to the "off the shelf" 416 LS3 that Katech already offers?

Thanks.

The main differences are:

1) LS9 Block (mine) vs LS3 Block (Katech). We can use an LS9 Block if somebody specs it that way.

2) 4.065 Piston (mine) vs 4.070 Piston (Katech). I chose not to hone out my block for now. The Katech 416 is a real 416 where mine is technically a 415.

3) 2.000" Rod Journal (mine) vs 2.100 (Katech). This is something I chose to use, this is also an option that anyone can custom order if they would like.

Essentially, the shortblock is the same. The biggest difference is the 416's sold to our customers are hand built by our engine builders. I am building mine myself. If inquired, we can throw together a custom shortblock based on application.

With that said, only the best quality can be expected from our shortblocks that we sell to the consumers.

[Nick S]

Originally Posted by Katech_Zach

The main differences are:

1) LS9 Block (mine) vs LS3 Block (Katech). We can use an LS9 Block if somebody specs it that way.

2) 4.065 Piston (mine) vs 4.070 Piston (Katech). I chose not to hone out my block for now. The Katech 416 is a real 416 where mine is technically a 415.

3) 2.000" Rod Journal (mine) vs 2.100 (Katech). This is something I chose to use, this is also an option that anyone can custom order if they would like.

Essentially, the shortblock is the same. The biggest difference is the 416's sold to our customers are hand built by our engine builders. I am building mine myself. If inquired, we can throw together a custom shortblock based on application.

With that said, only the best quality can be expected from our shortblocks that we sell to the consumers.

Thanks for the info Zach!

[olblue75]

Why did you decide to go with the Caddy lifters, Ive read they arent that great and can be somewhat noisy.

[Katech_Zach]

Originally Posted by olblue75

Why did you decide to go with the Caddy lifters, Ive read they arent that great and can be somewhat noisy.

They are more stable at higher RPM, it is a factor of safety for me. I won't be spinning more than 7000 RPM, the LS7 OEM lifters would have worked just fine.

We haven't had any issues out of the 100's of sets we have used here. The ceramic check ball can be noisy depending on preload and the valvetrain that is used with them. In general, they will be noisier than the LS7 lifter though.

Most bad reviews tend to come from lack of valvetrain control, improper preload, or using a spring that is way too stiff for the lifter.

[Katech_Zach]

Small Update: I am still waiting on a crankshaft, connecting rods, and head gaskets. I am hoping to get an update in the middle of next week. What I have left to do while I am waiting:

Chassis:

• Design Rear Spring Perch
• Design New Wheel Spacer
• Design New Wheel Hub Adapter
• Thread and Powdercoat Toe Links
• Replace Damaged Front Splitter
• Design and Powdercoat Tow Hooks

Engine:

• Design Valve Cover Modification for Oil Seperator
• Design Valve Cover Insert for Katech Valve Covers
• Powdercoat Valve Covers
• Port Throttlebody and Modify Shaft
• Design Intake Airbox

I disassembled my throttlebody and that is now off to cnc. I will most likely start the design process on everything tonight.

[Katech_Zach]

Some chassis updates: I finished up the tie rod ends for the car to correct bumpsteer. I started with the LSR kit that had the correct stud and heim. I then created my own body using 4340. This has the correct threads for the 14-15 power steering rack. The last thing I need to do is powdercoat them.

Update for anyone with Bilstein B6 shocks, the rear shock compresses the OEM spring roughly ~0.50" more than stock, causing additional preload on the spring. This effectively raises the spring rate and makes your rear end stiffer. The solution I came up with was modifying the Bilstein rear spring perch to drop an additional 0.50" on the snap ring seat. I also turned down the O.D. to match the OEM rear perch.

14-15 Bumpsteer Kit:


Modified Bilstein Shock: