[adamlee05]

I need two additional bolt holes on the back of a K20A2 for a TSX mounting bracket. This bracket has a total of four bolts, two which thread into the transmission and two into the block. Due to the design of the bracket, I'm not entirely sure proceeding with only using the transmission-side bolts would be safe/reliable and not cause damage to the trans/bracket/mount under heavy load (350-400whp) due to it trying to torque at unusual axes.

My question is, what are my options here? Outside of sourcing a CL7 K20A block, none of the K20's have these holes. Can material be safely added to the block? Could I trim material from the flywheel side of the block and create a sandwich plate between the engine/trans which angles over allowing me to bolt into it? I know this isn't a massive modification but it is needed for me to correctly mount this engine.

Really hoping to hear back from you guys on this :new_slayer:

TSX Trans

K24A2 Block

K20A2 Block

TSX Rear Mount Bracket (Upside Down)

 

[adamlee05]

Anyone?

:Ookay:

 

[signalpuke]

Why not just use the K24?

 

[adamlee05]

Why not just use the K24?

I prefer the higher R/S ratio and operating speed of the K20, and lower torque output. The lower torque will greatly help with low end traction, and should be easier on the trans vs a boosted K24. I already have terrible low end traction issues from the K24 even with an LSD.

This will also allow me to leave my original K24A2 untouched for the most part and be a backup if ever there were a major issue.

Also, its different yet still very practical. I'm unaware of any K20 powered CL9's in the States, or anywhere in fact.

The K20A2/K24A2 frank only cost me $250 as well.

 

[adamlee05]

No welder/fabricators in the Welding and Fabrication forum with knowledge on the subject?

 

[signalpuke]

You can give it a shot, but the block is cast, and that will likely be the weak point.
You say you want lower torque, but you are supercharging the engine, which will produce more torque than the K24...

 

[adamlee05]

You can give it a shot, but the block is cast, and that will likely be the weak point.
You say you want lower torque, but you are supercharging the engine, which will produce more torque than the K24...

Yah I know, I'm fully aware a boosted K20 is going to out-torque an NA K24
But the boosted K24 is going t o give me excessive torque, and I don't want that. The car needs more power, but not necessarily excessive low RPM torque. Also, it's going to be turbocharged either way, and I prefer the K20 for my application.

I've done all of this before, its not new to me. Just this particular engine in a TSX chassis is.

It seems none of the fabricators are going to chime in, you can delete or lock if you'd like. As always, thanks for contributing again Signal!

:alone:

 

[jdchmiel]

it 100% can be done, but is very unlikely to be cost effective. Bare block, weld it up, who machine the bosses flat and then drills and taps them? Then all tolerances need to be checked and fixed to assemble. Strong possibility exists the block could crack unless done very well.

 

[02sik24a2]

Al likes to be hot when welded. Requires very clean weld prep. The block would have to be heat treated where the welding something smaller to the block takes place.

I would not do this b/c cast Al welds dirty. So there is something that can be done.

Obtain a thick Al plate. weld what ever you want to the plate. seems like you want a strong connection and a high stress point. you could weld two seperate plates to, with a hole centerlined on both. Then you can weld the, bearing plate to the block. By cleaning the block and pre-heating both plate and block.

Then take your time going around the plate. Back grinding start and stops. Also round all four corners of the plate. That way there will be full burn in at the corners, as the welder does not have to pause at the corners, yet keep welding.

I hope that helps.

 

[02sik24a2]

If you do the plate type for additions to the block, you can tap them and bolt to the plate.

A few holes can be drilled in the plate before welding it to the block. so you can tack weld it to the block before welding the edges

 

[kb58]

I would build up a separate sub-frame that picks off existing holes. That's what I did for the shift cables on my mid-engine setup:

 

[01H2BITR]

1. preheat
2. tack it up
3. weld