Performing Honda K24a3/AST5 6spd Conversion

[dcioccarelli]

K-Tuned TPS finally came - I'll try to get it installed before school starts on Tues. Not cheap, but supposedly better constructed than the typical aftermarket.
...
just a 'billet' cover over the JT7H TPS - this cover may be too bulky to install in my setup

Well, at least you have the right part number to look for now . Searching on eBay for JT7H TPS reveals plenty of low cost options, even Honda ones for around $17.

 

[lookforjoe]

Well, at least you have the right part number to look for now . Searching on eBay for JT7H TPS reveals plenty of low cost options, even Honda ones for around $17.

Yes - once I found that part number, I looked it up and found one through AM Autoparts that has a 10-year warranty! So I ordered one of those just because it was only 12 bucks

 

[lookforjoe]

Back to the overheating whilst running issue -

EDIT (Nov2020)- problem (besides HG) is due to coolant temp drop between block & t/stat housing. running 160º T/stat brings operating temps back into the 180-190 range

I'm going to do a leak down test in the next couple days - there is a significant coolant flow issue - just running it at idle the t/stat hose is not heating up, and the radiator is also cool on the output side. ECT is registering temps over 220ºF. If I bleed the rad, I can get the temp up at the t/stat, but, if I keep it running the hose cools off again. I can only assume whatever blowby I have is creating air pockets, and inhibiting proper flow. I've personally never experienced it like this though, since there is not overpressure in the cooling system as one would expect..

I did pull the t/stat & swap it for another, it made no difference. I was also wondering if the water pump impellers fail on these motors - Just trying to cover every possible aspect that would screw with the circulation.

The only other question would be regarding the K-Tuned water outlet on the side of the head - I don't know if that could be an issue, raising the head temps

 

[lookforjoe]

So, I did compression & leak down tests today. 190 on 1&4, 175 on 2&3.

3 Cylinders leak into the coolant system - there are very slight burbles I can hear in the reservoir.

The plugs were also affected by the excessive temps over the past 50-80 miles I had driven it seems - all four were at least .005" too wide (.049", Max is supposed to be .044").

That doesn't really explain why the circulation is blocked through the T/stat, though. At least I know for certain I need to do the head gasket.

After that, I removed the t/stat & put a gutted one in it's place. With that, I have full circulation - the t/stat return hose warms up nicely & coolant temp runs up to 195-200ºF idling. If I let it sit with the cooling fans on, it drops to about 180ºF

So, I'm trying to understand what about the t/stat is causing the flow restriction.

 

[kmead]

So, I did compression & leak down tests today. 190 on 1&4, 175 on 2&3.

3 Cylinders leak into the coolant system - there are very slight burbles I can hear in the reservoir.

The plugs were also affected by the excessive temps over the past 50-80 miles I had driven it seems - all four were at least .005" too wide (.049", Max is supposed to be .044").

That doesn't really explain why the circulation is blocked through the T/stat, though. At least I know for certain I need to do the head gasket.

After that, I removed the t/stat & put a gutted one in it's place. With that, I have full circulation - the t/stat return hose warms up nicely & coolant temp runs up to 195-200ºF idling. If I let it sit with the cooling fans on, it drops to about 180ºF

So, I'm trying to understand what about the t/stat is causing the flow restriction.

Isht. Sorry for another bump in the road for you.

 

[NEG]

That’s bad luck Hussein, stupid question but can the stat go in the other way ‘round...

 

[lookforjoe]

Isht. Sorry for another bump in the road for you.

Yeah - I was expecting to drop the drivetrain anyway, to finish the subframe welds, etc.

Since I'm dropping it, I'm also putting in a 4:00 MFactory FD gearset. I'm not going to want to drive distances if I leave the setup as it is - the cruise rpm is way too high to be comfortable (esp. if I want my wife to accompany me).

So, I do the HG & have the head rechecked for square, fix the AC compressor mount ear, do the water pipes, and see what if anything else was damaged

That’s bad luck Hussein, stupid question but can the stat go in the other way ‘round...

Nah. Has to be that an air pocket is collecting from the blowby to the cooling system, and the t/stat must have been a convenient place for it to occur. On my morning drive to work (6am) the motor didn't ever get above 160F. I'll put the t/stat back when the HG is fixed.

 

[homegrown32]

I had a very similar issue with mine and idol. If I let the car idle in 60° weather it would overheat with the radiator cold to the touch. But driving there was no problems. So I put a Davis Craig EWP-80 in at the radiator. I cycle it on and off using the fan relay from the Honda computer. I move the temperature down a little bit so it doesn't kick on at 190 but more like 185 or 180. I turn the fans and the water pump on at the same time. Now in 100° weather in traffic after a hard freeway run. The fan and EWP just cycles about 15 seconds on and 30 seconds off.

 

[homegrown32]

Sorry I not intend to post the same image three times. But to summarize I think that the Honda water pump at idle does not like the long coolant lines and bends that it takes to run through the Fiat system. I also have an under-driven pulley and assumed that was part of my problem.

 

[lookforjoe]

I had a very similar issue with mine and idol. If I let the car idle in 60° weather it would overheat with the radiator cold to the touch. But driving there was no problems. So I put a Davis Craig EWP-80 in at the radiator. I cycle it on and off using the fan relay from the Honda computer. I move the temperature down a little bit so it doesn't kick on at 190 but more like 185 or 180. I turn the fans and the water pump on at the same time. Now in 100° weather in traffic after a hard freeway run. The fan and EWP just cycles about 15 seconds on and 30 seconds off.

Sorry I not intend to post the same image three times. But to summarize I think that the Honda water pump at idle does not like the long coolant lines and bends that it takes to run through the Fiat system. I also have an under-driven pulley and assumed that was part of my problem.

Thank you for the input & specific details. With mine, it overheats under any circumstance with the t/stat in place. Once I fix the HG, I'll have to re-assess whether additional measures are required. I will be adjusting the fan onset temp with a lower temp fan switch, for starters.

 

[lookforjoe]

MFactory 4.00:1 FD set came. Once I get the car back from the body shop (taking it tomorrow for paint) I will pull the drivetrain & move on with the rest of the work.

Revising the sway bar end link attachment on the control arms. What I had has actually been fine for the past ten years, but with the frame damage & repair, the mount angle of the sway bar has shifted (surface there is now flat, instead of stepped), moving the link connection rearward.

So, I'm doing what Doug suggested quite some time back - converting the end links from the bushed style to the more rigid high-misalignment balljoint style (same as the rears, using Volvo/Mazda/Ford units)

This is current:

New brackets under construction , which could also support existing design end links

I will make a collar that locates the stud centrally in the arm, where the bushing currently centers

 

[kmead]

Does that want to be a hardened washer? Given it is a small distance it is unsupported.

How well does a ball joint like that work with a pull load? I haven’t seen many set up like that but I don’t get out much...

 

[lookforjoe]

Does that want to be a hardened washer? Given it is a small distance it is unsupported.

How well does a ball joint like that work with a pull load? I haven’t seen many set up like that but I don’t get out much...

View attachment 36556

Hi Karl

I'm adding an internal sleeve so that the existing washer (integral to link) and the top washer will have an interference fit in the bar. I have some hardened (bevelled) washers from the CEIKA brake kit, so I can use that if need be. I could also weld an insert/flat in place, if it appears that maintaining a rigid connection at that point is problematic.

These are intended for sway bar mounting - I have them on my C30, and on the rear (Acura) swaybar on the X1/9 - can't link reference pics from here, I'll add later.

 

[kmead]

Thanks. Our Honda has some that seem to break down faster than I would hope, they are both a 90° connection like your lower half. The aftermarket ones sold for the Honda we have seem to be even worse than the Honda ones so I bought OEM ones.

Nice set up for what you have created.

 

[lookforjoe]

Thanks. Our Honda has some that seem to break down faster than I would hope, they are both a 90° connection like your lower half. The aftermarket ones sold for the Honda we have seem to be even worse than the Honda ones so I bought OEM ones.

Nice set up for what you have created.

That sucks. For these, the aftermarket (name brands) are decent - I put mine in (on the C30) 5 years ago when I added the Corksport Mazda rear bar.

I got the main brackets finished today, and made one of the 'top hats' to properly locate the link in the sway bar. Hopefully get the other one made tomorrow.

Modded the metric tow hook to fit the SAE captive nut in my frame rail

 

[lookforjoe]

Endless problems with the sway bar mount bushings.

new one on left - 1273615 - supposed to be 22/23mm ID

so, I ordered the other number 1273184 -

so, neither on is correct, even though my originals are embossed with 1273165

If I can't locate a proper replacement, I will have to use poly bushings, which don't have the proper bracket offset.

Stock bushings locate in the two brackets:

To make them work, I need a 1" spacer for the mount bracket - welded two 1" square tube together to make a spacer. Also going to use the nut plates here - which are X1/9 bumper shock brackets cut down.

 

[lookforjoe]

Since I'm in wait mode until my car is finished being painted next week, I've been fiddling around with odds & ends.

Ordered 23mm SuperPro poly bushings (SPF1025-23K) for the sway bar

Finally hooked up the water cooler & torch. Only took me a year or so to get around to it.

Made latches to secure the cooler with a Volvo spare wheel strap

welded the radius rods off the parts car back together - I had chopped them in two (about 4-5" from the threaded end) by accident when I cut the nose off

 

[lookforjoe]

Finished up the front sway bar install, with the revised end links and poly bushings

So, at this point I have driven the car with F & R bars and Rear bar only.

EDIT - this is with progressive rate QA1 F& R 2.5" coils - 140/250 , 10" F 175/350, 12" R

With just the rear bar, the rear end will push out very easily when cornering hard under load.

With F & R bars, the front end feels light & unstable/twitchy over irregular road surfaces, and the rear also pushes out too easily under high load when cornering.

With just the 23mm Volvo front bar, the car feels great, front end feels planted & no funny business at the rear.

so, for K-swap wide body conversions / wide track, larger & wider wheel & tires setup I would say stick to front bar only.

 

[lookforjoe]

K20Z3 Cylinder head is all cleaned/decked (.003") & valve train ultra-sonically cleaned to get all the high mileage crap out

He was just waiting for me to drop off the Honda valve seals. It will be ready for me on Monday.

while I was there - one of his customers with an old Trans AM Z28 (thanks Ulix ) came up - mere 1200BHP - around 800 without the supercharger

 

[dllubin]

Cylinder head is all cleaned/decked (.003") & valve train ultra-sonically cleaned to get all the high mileage crap out

He was just waiting for me to drop off the Honda valve seals. It will be ready for me on Monday.

View attachment 37810View attachment 37809View attachment 37808

while I was there - one of his customers with an old Trans AM came up - mere 1200BHP - around 800 without the supercharger

View attachment 37811View attachment 37813

Looks to be a Z28 Camaro.