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Is there any reason why they would leave it rich like that? What would be the thought behind it? Or is the tuning just not good?
Mmmmmhhhh...I assume we have two smoking functions here, one is low load oil smoking due to an efficiently low-tension two-ring system (best case ;)) and the second function is the tune itself under load. The start may release some collected oil (from a improper ringland oil houshold) in the exhaust pipe, pushed by WOT operation through the pipe. That so much of the oil still get vaporized and even smoked tells something about the excess fuel.

Many calibrations of these race NA engines, which I've corrected, came in with an Lambda of 0.85-0.89 at full load, I don't know why, as there is no reason to do so. If the is properly working best torque is reached in much leaner conditions. Some turbo racing series run near to Lambda 1.0 by class rules, these engines are prepared for that lean operation under full load. That I would call too lean for an stock K-series engine under WOT. Transient fueling is another source of overfueling, but that would take me too long to go into that topic.
 
Very interesting. Thanks for the information here.

I would figure in a competitive environment making sure the tune is perfect is very important! As we know sometimes it can take little extra work but the end result speaks for itself
 
Discussion starter · #125 · (Edited)
Interior dry build no. 2, can never do this too much to make sure everything is right!

Seat / pedals / wheel all good. Seat needs a slight tilt forward / raise rear height so we'll make spacers.

Foot plate needs raised and a heel stop for accel & brake pedals (left foot braking).

Switch panel console needs the pots fitted for TCT / PAS, TCT wet / dry switch, camera and master kill (can do this through the switch panel but making it idiot proof) before welding joins then making from carbon.

Fuel / air boxes need relocated further back, especially fuel.

Start prep on fuel / air / oil bhd covers to make from carbon / nomex.

Cut both fuel & air box side panels and repanel with carbon / nomex.

Test fit front brake pressure sensor to make sure there's no clash with the ECU / PDM panel.

Couple of little "tweaks" to internal panels.

Rivnut / stud both box mounting points & k-nut.

Rollover pipe to floor pan.

Final fasteners for brake / air lines.

Windows out in prep for paint and remove dash sound deadening.

Mount PAS ECU & battery.

Fit / test / rinse and repeat until 100%!

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Also measured for full droop / compression today, needed to check we're within camber limits without having to move the strut towers further outboard. Max compression gave around - 2.75deg so think we're good as is. This also gave us max delta between droop and compression for getting linear potentiometers on order for suspension data logging.

Fitted inner lobros / outer CV's and measured for driveshafts. Easiest way to do it was the good old string method and two pairs of hands! And even with the LCA's wound in nearly all the way, the JAS arches still need a slight pull outwards for clearance on full compression so front track is definitely plenty wide enough!

Dummy engine also now out, can now start prep on the engine bay and it'll let us split the bellhousng from the box to drill holes for clutch hoses then throw a crank in with flywheel / clutch, bellhousng back on and measure for release bearing fulcrum / spacing. It'll be good to get this done ASAP so we can get it back in with sensors on to start making the loom. It'll also impact radiator / pump placement and these need done before thinking about engine bay paint! Hopefully updates will be more fluent now the proper prep is underway!

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Discussion starter · #126 · (Edited)
Managed to get a coupe of jobs done before heading away with work...

Rear brake carriers don't fit the setup anymore due to changing to DC5 hubs. Instead of getting new carriers made, we flipped the existing ones then made some spacers on the lathe after some careful measuring. Also decided to ditch the PCI rear camber / upper arms. I had a chat with my race engineer about these and he didn't see much benefit in them (they push the mounting point inboard) relative to the EP3 rear setup. Swapped them back out for another set of Hardrace sphericals which is another substantial weight saving, the PCI arms are quite heavy.

Establshed max delta on droop / compression for the linear pots up front. Had to have a good think about how to mount these as the upper spring perch is free floating on the strut shaft. I think we'll end up pinning the upper perch to the shaft then use it and either the bottom strut arm or a clamped plate for the lower mount. Just need to make sure it all rotates in unison so there's no angular change to the pot during turn. The length of the pot was problematic as well if using motec so we've found an alternative which has a lot shorter body, and it can be ordered with pop joints which makes it a lighter connection assembly and a bit of a failsafe built in if things go wrong, these things aren't cheap! Work in progress.

Also noted the Moton upper knuckle bolt is only a 14mm whilst the knuckle itself is 16mm so we'll need to drill both struts out to 16mm. Sleeving would've been nice but press fitting a 1mm thk sleeve in would've been optimistic at best. I'll need to check if the bolts are 8.8 or 10.9 and look to replace with Ti and K nuts.

The PCI steering arms need stripped and measured. With the new LCA's / wider track, arms need measured to make sure we're not over extending on thread run out. Will most likely need either longer arms made or use longer threaded bar between arm and RJ. It's amazing how near enough every little job results in something needing more attention than you'd think! Just another fun little challenge along the road!

We had a meeting the other night (myself, no.1 hand, electrician) to run through everything to get the ball rolling for making the loom, eg, components, routing etc etc. No issues flagged really and should be straight forward once we've spec'd the fluid systems for additional sensors. Analogue input handling is relatively large for this build but we should scrape by between the M130/PDM15 & dash.

PAS should be relatively easy to setup variable assist so not quite sure why I've not read or seen someone do it with the EPS rack before.

Stock wiper assembly is 2.8kg, I've sourced a Bosch Motorsport WDA Direct Acting motor which comes in at 1.2kg. Managed to find one cheap as chips compared to new (about £700 new!!!) but it's analogue rather than LIN. Won't make much difference to me but LIN would have been preferable. Need to see if it fits in the space available, be nice if it does then can go about making a mount for it.

Rebuilt the dummy longblock with crank, FW / clutch assembly & the bellhousng from the box. Pen to paper for all measurements required for the clutch release bearing spacing, just need to figure out an alternative trumpet as the one supplied is way too big for the fingers on the small clutch. Will have that chat with the supplier of the box and see what the possible solutions are. Now that the box is back out and bellhousng off, we can drill the box for both clutch lines, one of many boxes still to be ticked.

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Decided to tidy up the front end whilst the longblock / box is out. There shouldn't be too much modification from where it's at now so seemed like a good idea to get a nice blank canvas to work on up front. We'll have small brackets etc to fit but can easy touch up after.

The forward transverse tube of the subframe will be cut out, plate the ends then put a much lighter tube in its place. There was a bit of thought about front end flex but think we'll be good to remove / replace. Nice place to reduce weight.

Just waiting for some blue steel rust killer to work it's magic before getting the bulkhead done.

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Discussion starter · #129 ·
Such a FW & clutch is high on the wish list
Nice bit of metal to look at right now. The sparky saw it the other night and was like, ooh, that looks nice. 😅

Can't remember what it weighed in at, think it was around 4.5-5kg all in, would need to check previous posts. I think with implementing DBW / blip we might avoid some of the serious engine breaking that'll come with it, still something to be mindful of for braking / corner entry. It's also going to be a hoot driving in the paddock / parking. 🙃

Sizing the trumpet is the only real issue to overcome, dia of the fingers is really small so think it'll need one made to suit rather than pick from the options that are available for the box. Find out soon enough.
 
Discussion starter · #130 ·
Today's the day for top coat in the engine bay and front inner arches. Be nice to see some champ white on there!

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Scuttle areas been left for now, hopefully the Bosch wiper motor shows up today so we can check for fitment and get a wee bracket / mount fabricated for it.

Windows out next week then the inside can get a lick of paint.

Also a last minute spot for a few more grams off, washer bottle mount! Must be at least 200g. 😁

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Discussion starter · #133 · (Edited)
Thanks David, making good progress now the shell's back. Seem to be ticking boxes off the to do list at a decent pace now.

Me neither so I was somewhat pessimistic about it being feasible but my friend who knows his stuff about the electrical side of life thinks it should be simple enough to implement. No vss with the seq box so it'll use the wheel speed sensors and the little box of tricks guys use for corsa EPS conversions. Hopefully getting it setup doesn't throw up any show stoppers but the sparky seems confident enough.
 
Discussion starter · #136 ·
Discussion starter · #138 · (Edited)
No weight saving today, it's starting to go back on... :cool:

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The Bosch WDA arrived today. One thing I wasn't aware of is these were basically made to order and you had to specify sweep angle / park position to suit application. I believe they'll be replacing with a newer model which will be end user configurable.

This one is 30-150deg sweep with 90deg park so think I've been quite lucky in way of it not being set for left / right seat position. Straight up the middle for this one with 1990's DTM vibes. 😁

Need to check for fitment but it's quite a small unit and think we can get it in there. (worth the effort for the 1.6kg saved vs OEM!)

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