Preparing For Honda K24a3/AST5 6spd Conversion

lookforjoe

True Classic
Finished up the coolant pipes for now. With the SS feed pipe, I just need a short 90º coupler off the head connection. I cut a new Gates hose for this.



Everything had clearance, if snug. Have to add a couple vacuum NPT fitting to the plenum by the TB flange.



Map is mounted on TB, underneath (on the right in pic, yellow tape marks location). May have to move it, as connector may not clear rad hose. Coolant sensor came from MWB, that will be fine with an elbow spade connector.



Going to follow Rodger's lead & remote mount the (Volvo/VDO) OP gauge sender under here (with a block mounted elbow housing).

1/8 " NPT - 4 AN fitting (x2)
6" braided 4 AN hose
1/8'' BSPT Oil Pressure Sensor Tee to NPT
Sender adapter plate - 1/8" NPT ports


Drilled a chunk of aluminum to make transition port/mount for the OP sender & feed hose. Sender will point straight out. Have to tidy it up/trim it down. MAy have to make it out of a chunk of brass. Not sure the aluminum is sturdy enough. The K24 has threaded bosses, which make this easier than on the K20.

 
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kmead

Old enough to know better
Looks good from Stuttgart, just like MB would make to go in that spot. Nice to see the minimized number of connections and well constrained attachment to the block. Being 6 hours off of the normal flow of info on the forum is kind of neat.
 

fiatmonkey

Tim Hoover
Leaving the intake for a couple days. Worked on the water pipe today. 1.5" center section, 1.375" downturn & ends. Still having some issues welding. My auto dimming helmet wasn't auto dimming immediately - I kept getting flare in my eyes, not good, couldn't actually see the weld puddle at least once on each weld. Tried playing with the sensitivity & delay. Seems like it's actually more to do with the precise angle I offer the tungsten up to the metal, which seems odd to me.

Basic layout with wiring & manifold in place.





Made SS support brackets for the pipe, using Volvo parts of course. They are the headlamp wiper stops from a 98-00 V70.



Downturn. Wasn't sure if I was dropping too low - but looking at Darwoodious's pic, I have around 6" or so from the (MWB) frame engine brackets down to the water pipes





Adding an elbow at the end, so I can use a plain 90º hose to complete the connection

EDIT - looking at some weld quality articles (SS, poor color welds), I have the amperage too high here. I set it on the low end of the scale (50amps), based on 16g SS, but that clearly is too high for this batch :(




clearance of the pipes from the top


Great job on the lower SS coolant line. Looks solid man. I killed my MIG a few months back and don't have space for my TIG at my place so I am really jones'ing it right now :(
 

hotx19

Daily Driver
IMG_6088.JPEG
I just wanted to mention this too you
I think you are using the late model fn2 civic type box like I am using
There is a couple of issues that I have run into the shifter linkage is different and will not work with the Midwest set up the linkage is on the opposite side you will need to change it to the early style shifter which is not hard
The other issue is the speed sensor it is different and sends a high frequency signal to the ecu
Obviously you will have to change to the early ecu and loom to accommodate the drive by cable throttle body that replaces the late model drive by wire system
That's when the issue arrives the late model sends a high frequency signal but the early model ecu needs a low frequency signal
So you have 2 options change to a early model sensor which requires you to take the box apart and fit the drive on the diff centre and drill the case to accept the sensor
Or by the module from ktuned which modifies the signal which is the way I am
Hope this helps
John
 

lookforjoe

True Classic
View attachment 15882 I just wanted to mention this too you
I think you are using the late model fn2 civic type box like I am using
There is a couple of issues that I have run into the shifter linkage is different and will not work with the Midwest set up the linkage is on the opposite side you will need to change it to the early style shifter which is not hard
The other issue is the speed sensor it is different and sends a high frequency signal to the ecu
Obviously you will have to change to the early ecu and loom to accommodate the drive by cable throttle body that replaces the late model drive by wire system
That's when the issue arrives the late model sends a high frequency signal but the early model ecu needs a low frequency signal
So you have 2 options change to a early model sensor which requires you to take the box apart and fit the drive on the diff centre and drill the case to accept the sensor
Or by the module from ktuned which modifies the signal which is the way I am
Hope this helps
John
Thanks for the heads up, John. Definitely want to resolve issues like this long before the engine is in the car!

With the shifter, it doesn't work at all, or the shift pattern is reversed? I've had that issue adapting shifter setups when converting older auto Volvos to a late manual trans. I'll have to look for the early 6 spd shift module. What year & model has the correct one?

I'll have to question KTuner on the speed signal (?) to the ECU. I'm using an '05 Accord ECU (K24) on their recommendation (to eliminate DBW) & my TSX K24 engine/trans is also '05. I'm using the '05 harness & all sensors, and repinning the DBW connector to feed the TPS & IACV instead.
 

lookforjoe

True Classic
i think you will need 02-04 type s wire harness .
Why? Can you elaborate? The '05 Accord ECU works with the '05 TSX setup (cam/crank/knock sensors etc.,), I just need to rewire for TPS & IACV.



KTuner also said no issue with the AST5 6 speed VS sensor, the 5 speed ECU just won't register the additional gear, apparently.
 

TonyK

True Classic
Leaving the intake for a couple days. Worked on the water pipe today. 1.5" center section, 1.375" downturn & ends. Still having some issues welding. My auto dimming helmet wasn't auto dimming immediately - I kept getting flare in my eyes, not good, couldn't actually see the weld puddle at least once on each weld. Tried playing with the sensitivity & delay. Seems like it's actually more to do with the precise angle I offer the tungsten up to the metal, which seems odd to me.

Basic layout with wiring & manifold in place.





Made SS support brackets for the pipe, using Volvo parts of course. They are the headlamp wiper stops from a 98-00 V70.



Downturn. Wasn't sure if I was dropping too low - but looking at Darwoodious's pic, I have around 6" or so from the (MWB) frame engine brackets down to the water pipes





Adding an elbow at the end, so I can use a plain 90º hose to complete the connection

EDIT - looking at some weld quality articles (SS, poor color welds), I have the amperage too high here. I set it on the low end of the scale (50amps), based on 16g SS, but that clearly is too high for this batch :(




clearance of the pipes from the top

Hussein when welding stainless steel, good fitment makes better welds. Use a .040" tungsten at 25 amps DC start the puddle, you may need to add just a bit of filler metal to start the puddle then weld without filler. I only weld 80% through and don't have to worry about burning or slag on the inside of the pipe.

For Aluminum on the runners. Get propane torch and fire it up and let it heat the runner as you weld it. Sure it will get hot, but you can lower your amperage on the TIG torch and the metal will flow out better.

TonyK

Grimsby Ontario Canada.

IMG_0783.JPG
 

lookforjoe

True Classic
Hussein when welding stainless steel, good fitment makes better welds. Use a .040" tungsten at 25 amps DC start the puddle, you may need to add just a bit of filler metal to start the puddle then weld without filler. I only weld 80% through and don't have to worry about burning or slag on the inside of the pipe.

For Aluminum on the runners. Get propane torch and fire it up and let it heat the runner as you weld it. Sure it will get hot, but you can lower your amperage on the TIG torch and the metal will flow out better.

TonyK

Grimsby Ontario Canada.

View attachment 15898
Many, many thanks for the specific info, Tony. Yeah, some of my angle junctions don't align without some gapping. I will have to work at being more precise with the prep. That is much lower amperage than I would have considered, and I think I was using 1/16" tungsten - not sure I have collets for smaller than that, I will check & get supplies if not.
 

TonyK

True Classic
Many, many thanks for the specific info, Tony. Yeah, some of my angle junctions don't align without some gapping. I will have to work at being more precise with the prep. That is much lower amperage than I would have considered, and I think I was using 1/16" tungsten - not sure I have collets for smaller than that, I will check & get supplies if not.

Here are a few shots of my exhaust system on my 79 X with the Fiat X1/9 engine. You can see how the welds come out. Filler metal is MIG wire to start the puddle, .024".

This should give you an idea of how delicate the welds can be. On the larger pipe I needed a section of 2 1/4" pipe but no one had it, so I cut a section out of the 2 1/2" pipe and TIG welded it to make 2 1/4" pipe.


TonyK.

Grimsby Ontario Canada.

P1110330.JPG
P1310384.JPG
 

lookforjoe

True Classic
View attachment 15882 I just wanted to mention this too you
I think you are using the late model fn2 civic type box like I am using
There is a couple of issues that I have run into the shifter linkage is different and will not work with the Midwest set up the linkage is on the opposite side you will need to change it to the early style shifter which is not hard
John
Any more info on this, John? I looked up the parts from a 2002 RSX, which I assume falls under early style. In your pics the bolt pattern of the housing looks different between the two. I can't find any listings for used parts, so if I have to order shifter parts I'm trying to figure out exactly what to get. Is the solenoid mount to the housing also different? I can see the base & lever have to be changed, just don't know what else, if I have to order new individual parts. The diagrams use the same drawing for the housing, but that is clearly different given the pivot location.

TSX:



RSX:



EDIT: Since my housing doesn't have the webbing, I may be able to just get the pivot arm (never mind, vent tube is in the way)...

EDIT: Just found a new listing for the correct shift arm for $100 - cheaper than othe listings I found, which were over 200, and less than buying new parts to try & adapt
 
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hotx19

Daily Driver
I bought the complete arm from a 2002 6speed
The bolt pattern is different but the holes are already in the case just need to be tapped
It's a straight forward swap
 

lookforjoe

True Classic
I bought the complete arm from a 2002 6speed
The bolt pattern is different but the holes are already in the case just need to be tapped
It's a straight forward swap
Thanks John, that's the important piece of info :)

This is the one I have coming

 

lookforjoe

True Classic
I bought the complete arm from a 2002 6speed
The bolt pattern is different but the holes are already in the case just need to be tapped
It's a straight forward swap
Hey John

Did you have any issues with the inner axle? The one off the TSX won't work, and the first one I bought sold under the 44500-SCV-A00 part number (02-06 RSX type S) doesn't fit - the bracket sticks too far out from the block.



I see some have aluminum brackets, some have cast iron. Trying to figure out what I need to get to avoid $$$$ and aggravation...

TSX axle offset



Length difference between TSX / RSX inner axle

 
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lookforjoe

True Classic
taken from here

I haven't completed headers on the latest build, but I am interested in how it will work running it that way. My 75 had a similar geometry as the pic Hussein posted but I added a flex joint after the hard left bend.

View attachment 15860
Do you have pics of the headers you built? What size tubing did you use? The shorty header flange definitely needs opening up if it is to be used, there is a wall that the exhaust will hit, right at the flange. I'm thinking 1.75" tubing. Is that what you used or did you go larger? Flange openings on factory manifold are close to almost 2".
 

lookforjoe

True Classic
Shifter came. The flange surface is machined where the alt style bolts up, but... there is a step where the outer bolt needs to go, and no marker of any kind where the drilling will have to go. Just means I have to be very careful about marking & drilling the holes perpendicular to the housing..

Gap under this rear one will need a machine gauge shim


This one sits on the already machined flat



Mark, drill to depth of approx 20mm & tap M6x1.00





Modified shim (washer) to compensate for offset of machined plane to drilled surface


I'm thinking 2" OD SS304 piping & elbows for a header.



Stock manifold actually has larger ID orifices than the shorty header, header has smaller ports, marginally larger ID tubing.



I'll probably use the factory flange, I think it will be less work than hogging out the header flange.
 
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lookforjoe

True Classic
Here are a few shots of my exhaust system on my 79 X with the Fiat X1/9 engine. You can see how the welds come out. Filler metal is MIG wire to start the puddle, .024".
This should give you an idea of how delicate the welds can be. On the larger pipe I needed a section of 2 1/4" pipe but no one had it, so I cut a section out of the 2 1/2" pipe and TIG welded it to make 2 1/4" pipe.
TonyK.
Grimsby Ontario Canada.
Tony, do you use welded or seamless SS pipe?
 

lookforjoe

True Classic
Oil pressure T fitting finally showed up, so I fitted it & checked overall hose & OP adaptor placement.

Clears Oil cooler and feed hose





Tucks up & under Oil Cooler. Snug to block, well away from axle & CV joint





Just need to refine/clean up OP sender adaptor block to make it pretty.

 

lookforjoe

True Classic
While I was taking the T/stat housing off the junk 500 motor, I realized the vent pipe would work well for the K24 install...

Removed M10x1.5 quick release fitting (next to vent pipe I snapped off Honda housing) from the 500 T/stat housing -



removed Honda pipe, drill with "S" bit & tap M10x1.25



500 expansion tank vent pipe. I'll trim it when motor & tank are installed

 
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