kmead
Old enough to know better
The incremental improvements are what development is all about. Nice work. Hope these changes solve the issues.
Performing Honda K24a3/AST5 6spd Conversion
- Thread starter lookforjoe
- Start date
lookforjoe
True Classic
revised the fuel filter mounting to give the air filter more room - the way I had it set the air filter base was pressed up against the fuel filter
The other ongoing issue is the header. The flange was warped pretty badly when I had to rework the header. I'm using a thick P2R graphite gasket, and there is still signs of sooting on the VC above the flange. I don't hear any leaks, but this will have to be addressed. The flange is too thin to be machined - I used the factory manifold flange as the eBay header version had poor port shaping. I see that all aftermarket flanges tend to be 1/2" thick to help mitigate weld distortion.
What I wanted to do, was use a header like this:
which would give me better runner length (K20a members all point out shorty headers loose torque on NA setups) - but... they are around 6.5" depth off the flange. I only have 4.5" between valve cover & crossmember
I'm going to talk to my machine shop & see if I can rework my header with a new flange. I don't know if it will hold up if cut & rewelded. I don't really want to make a new one from scratch
The other ongoing issue is the header. The flange was warped pretty badly when I had to rework the header. I'm using a thick P2R graphite gasket, and there is still signs of sooting on the VC above the flange. I don't hear any leaks, but this will have to be addressed. The flange is too thin to be machined - I used the factory manifold flange as the eBay header version had poor port shaping. I see that all aftermarket flanges tend to be 1/2" thick to help mitigate weld distortion.
What I wanted to do, was use a header like this:
which would give me better runner length (K20a members all point out shorty headers loose torque on NA setups) - but... they are around 6.5" depth off the flange. I only have 4.5" between valve cover & crossmember
I'm going to talk to my machine shop & see if I can rework my header with a new flange. I don't know if it will hold up if cut & rewelded. I don't really want to make a new one from scratch
jimmyx
True Classic
I have a thick aftermarket stainless flange that I used as a heat sink when I had my header done. Expensive heat sink, but it served it's purpose and I'm done with it. If you need it send me a PM and I'll send it to you.
lookforjoe
True Classic
If I went under - I would have problems with it scraping on every speed bump in town...
If I made the header longer into the exhaust cavity, I would have to lose the resonator. The exhaust is already too loud.
kmead
Old enough to know better
Aaah. I forgot about the subframe they added versus the way an X cross member allows for something alongside it.If I went under - I would have problems with it scraping on every speed bump in town...
If I made the header longer into the exhaust cavity, I would have to lose the resonator. The exhaust is already too loud.
My apologies. Thanks for the pic to clarify the space available.
lookforjoe
True Classic
Many thanks. Hopefully you can see it in person at MWB
kmead
Old enough to know better
I would be more pleased the meet the person
I am sure there is something that needs to go in the back of the Volvo pickup if that is the backup.
lookforjoe
True Classic
Car show in town yesterday - Exotics & European Sports Cars - of course, some Japanese and American cars made it as well, just not the typical Corvette Mustang / Camaro / Charger dominated lineup we usually have
staging area outside of downtown
staging area outside of downtown
lookforjoe
True Classic
Yeah, there were 2 Ford GTs. I'd like that car.
To ride in that thing? For sure! I found out after posting those pics on FB, that that guy is actually the younger brother of a former student (now in her mid 30's)
lookforjoe
True Classic
I finally did the compression & leak down tests, and put in new plugs NGK 1ZFR6K11 gapped @ .035" - I'm going back to the dyno to re-tune tomorrow, he recommended the gap based on expected performance.
Compression was 200 even on all 4 cylinders (hot engine, throttle open)
I could not find any leakage doing the leak down test afterwards - made sure each cylinder was TDC - couldn't hear any leakage via exhaust, intake or dipstick. I'm assuming the issue is (one or more ) valve seal on #4 - the plug is wet with oil
4 3. 2. 1
also got the US Acura trim cover to hide the backwards facing "HONDA" - flipped the emblem
Compression was 200 even on all 4 cylinders (hot engine, throttle open)
I could not find any leakage doing the leak down test afterwards - made sure each cylinder was TDC - couldn't hear any leakage via exhaust, intake or dipstick. I'm assuming the issue is (one or more ) valve seal on #4 - the plug is wet with oil
4 3. 2. 1
also got the US Acura trim cover to hide the backwards facing "HONDA" - flipped the emblem
jimmyx
True Classic
That really bothered me as well. Just ground it off before I "wrinkled" it.
kmead
Old enough to know better
I think I would put a continuous plate under that to make the text really pop.
That’s really nice.
lookforjoe
True Classic
Back at the dyno - numbers came out much the same as before. Starts pushing soot & oil smoke out the exhaust over 7K. Logs show it running rich up there - as no amount of fiddling with cam & ignition advance & pulling fuel made any real difference. It seems I need to make a better header to deal with the excessive back pressure causing the rich condition.
He refined the tune, and I do have more cam advance than before. It feels really good on the road, so I feel good about driving it out to Ohio.
I stopped at the machine shop too discuss the oil in the cylinder. He is adamant that even if I have damaged valve seals on #4 that couldn't be responsible for oil getting sucked out at high rpm. One thing he raised is the possibility of a flaky injector washing the bore at high rpm - that would conceivably account for the oil. The RDX 410cc (16450-RWC-A01) injectors I bought (3 years ago now) were genuine Denso, but reman units. I ordered new ones from Honda to be safe.
He also questioned using synthetic oil. I was already planning on changing the oil & filter today for the drive (2700miles on motor), so I used 5qts 5w20 conventional oil instead the 5w30 I was using.
He refined the tune, and I do have more cam advance than before. It feels really good on the road, so I feel good about driving it out to Ohio.
I stopped at the machine shop too discuss the oil in the cylinder. He is adamant that even if I have damaged valve seals on #4 that couldn't be responsible for oil getting sucked out at high rpm. One thing he raised is the possibility of a flaky injector washing the bore at high rpm - that would conceivably account for the oil. The RDX 410cc (16450-RWC-A01) injectors I bought (3 years ago now) were genuine Denso, but reman units. I ordered new ones from Honda to be safe.
He also questioned using synthetic oil. I was already planning on changing the oil & filter today for the drive (2700miles on motor), so I used 5qts 5w20 conventional oil instead the 5w30 I was using.
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lookforjoe
True Classic
Couple small updates to keep track of things - 2850K miles when I left for MWB open house.
Oil temps are better with the duct I added - never went up to 220 (mostly around 200, I'd gauge) even with hours of driving @ highway speeds in very high ambient temps Thursday & Friday on the way to Carlisle PA & then Columbus Ohio
Switched to conventional 5W30 motor oil - makes no difference to oil consumption - used a quart over the course of the past 3 days. No visible oil smoke on deceleration with the VTA breather setup though. Definitely have oil smoke when idling hot & then accelerating from a standstill.
The AC hoses have held up for over 700 miles of driving the past 3 days, with numerous spirited pulls that would stress the fittings, so the revisions with brackets seem to be doing the trick. I noticed on the drive that the AC seems to drop out under higher load/acceleration - however on Friday morning I was driving for hours with no AC - and I observed that the heat was coming on (I have a bay-mounted vacuum controlled heater valve with an ancillary reservoir) - so, I need to revise the system to maintain vacuum to the valve under those conditions.
I really would like to have cruise control for these long drives also
Friday - following Brian in his wife's 500 Cabriolet - it was great to have company & enjoy their tremendous hospitality
Oil temps are better with the duct I added - never went up to 220 (mostly around 200, I'd gauge) even with hours of driving @ highway speeds in very high ambient temps Thursday & Friday on the way to Carlisle PA & then Columbus Ohio
Switched to conventional 5W30 motor oil - makes no difference to oil consumption - used a quart over the course of the past 3 days. No visible oil smoke on deceleration with the VTA breather setup though. Definitely have oil smoke when idling hot & then accelerating from a standstill.
The AC hoses have held up for over 700 miles of driving the past 3 days, with numerous spirited pulls that would stress the fittings, so the revisions with brackets seem to be doing the trick. I noticed on the drive that the AC seems to drop out under higher load/acceleration - however on Friday morning I was driving for hours with no AC - and I observed that the heat was coming on (I have a bay-mounted vacuum controlled heater valve with an ancillary reservoir) - so, I need to revise the system to maintain vacuum to the valve under those conditions.
I really would like to have cruise control for these long drives also
Friday - following Brian in his wife's 500 Cabriolet - it was great to have company & enjoy their tremendous hospitality
