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As promised I’ll try to document here my progress of building the engine and things around it, maybe I would an advise as the work progresses.
Pretty much stock at the moment, but I’ve got few bits already and soon will tackle the task to put everything together ni

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Arouse the DAMPFHAMMER!
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...Pretty much stock at the moment, but I’ve got few bits already and soon will tackle the task to put everything together ni
Thanks for posting Mugen_fn2. Seems to get serious 🆙. I've tuned a FN2 engine in South Africa years ago for racing and daily driving. The stock RSP IM made a good job, will be hard for the RRC IM to keep up with. Didn't you post you have also RRC camshaft's to widen the usable engine speed bandwidth?

I've recently done a RSP intake runner cut to get it keep up with the RRC IM.

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Cut and rewelded. It's a cheaper affair as buying the expensive RRC and brings it on par even at the top end of the engine speed bandwidth.
Which header do you plan to implement? The K-series head, especially the RSP head, has a great flow efficiency and volume flux numbers over valve lift and are very sensitive to the header design (scavenging phase efficiency over engine speed). Playing with header length and diameters on either a 4-1 or 4-2-1 design gives one huge differences in the torque curve and transient response.

Are you keeping the AFM sensor or are you going to tune it in Speed-density mode via MAP, IAT and Engine Speed Sensor?
 

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@LotusElise Yes, FD2 cams and TB.
I don’t have the means and knowledge to do RSP porting myself and managed to get a very good deal on RRC. Among of all stock manifolds RRC gives the most gains, especially at the top which is what we all want. I know someone who does RSP porting job, but it’s mate of my mates cousin so to speak - not tested, no dyno proofs etc.
I know regarding the header, but I’m planning to hit the track soon and don’t want to do it without buffled sump and pump. As I have to take everything off - makes sense to get everything done in one go and forget about it.
I will go with the custom 4-2-1 exhaust manifold from Solid Fabrications and most probably Fujitsubo Powergetter. I know it’s a bit more restrictive catback than 3”, but it sounds amazing and this is my only/family car and I will try to stay civilised as much as I can.
MAF sensor will stay (I’ve got Tegiwa closed intake with driven crazy scoopin) and the mapping itself will be done by Paul West - he is a reputable person on the Honda scene in UK.
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@KBuilt I will try to get to RRC as close as possible and staying OEM. Imo fn2 is down on power and should be at least 225 from factory.
 

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Arouse the DAMPFHAMMER!
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Yes, FD2 cams and TB.
Very nice :).

I will go with the custom 4-2-1 exhaust manifold from Solid Fabrications and most probably Fujitsubo Powergetter. I know it’s a bit more restrictive catback than 3”, but it sounds amazing and this is my only/family car and I will try to stay civilised as much as I can.
That's a nice approach. Do you have any ideas about the design (lengths, diameters)?

MAF sensor will sta...
Ok, makes tuning session shorter 😉.

...mapping itself will be done by Paul West - he is a reputable person on the Honda scene in UK.
Oh, I know Paul. I've supported him once he had a mess tuning a hill climb car on an AEM Infinity. And I know him also from two of his customers at TDI North, which asked me to correct his tunes of their engine calibrations. Yeah, he is definitely well known.

I will try to get to RRC as close as possible and staying OEM. Imo fn2 is down on power and should be at least 225 from factory.
I like your OEM approach, with the CAI and Header as well as the exhaust it is very likely to see 240 flwhp, highest I think 255 flwhp if the exhaust header combi is very good. I've tuned some RRC IM swapped K20A2 engines with stock 11.5:1 compression and a 2.5" exhaust plus a good 4-2-1 header, all of them went over the 240 flwhp borderline and maxed out the stock injectors. Therefore I recommend to you to swap the injectors for e.g. RDX injectors to get the power limit dictated by your engine, not by the injectors 😉. But Paul maybe told you that already, should be your tuners aim to advise you before the tune to manage all issues also before the tune happens instead of costing additional time and money to heal out. At least it is my approach to clarify all necessary items before incl. healthy tests of the engine before start of any modification.
 

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Oh, I know Paul. I've supported him once he had a mess tuning a hill climb car on an AEM Infinity. And I know him also from two of his customers at TDI North, which asked me to correct his tunes of their engine calibrations. Yeah, he is definitely well known.
Haha, sounds a bit sarcastic to me. Do you think there is some better Honda tuners around UK? I haven’t used his service personally, but many did including racing support etc. and spoke highly about him. Sure everyone does mistakes, Paul included.
Do you tune cars for work, if you don’t mind me asking, that you had a chance to work with him?

Therefore I recommend to you to swap the injectors for e.g. RDX injectors to get the power limit dictated by your engine, not by the injectors 😉.
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I actually got them not even asking anyone. From the research I did on standard 310cc I understood that oem injectors will be maxed out quite quickly and I want reliable, linear power. Plus I will be swapping IM so makes sense to do it anyway.
Not chasing crazy numbers, but guessing 240-245bhp on the fly is achievable.

What do you reckon I will make with:
Tegiwa intake, RRC IM, FD2 cams, FD2 pump, RDX injectors?
 

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Arouse the DAMPFHAMMER!
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Haha, sounds a bit sarcastic to me.
Maybe 😉.

...I actually got them not even asking anyone. From the research I did on standard 310cc I understood that oem injectors will be maxed out quite quickly and I want reliable, linear power. Plus I will be swapping IM so makes sense to do it anyway.
Very good!

...Not chasing crazy numbers, but guessing 240-245bhp on the fly is achievable.
Yes, the A-type cams will add around 10-15 hp compared to the A2-type cams as the RRC support the higher peak power speed of around 8300 rpm instead of 7800-8000 rpm plus the better VE everywhere will lift that thing definitely to fun mode. The Z4-type cams are VE-wise in between the A-type and the A2-type. Concluding the combi of RRC IM, A-type cams will be anyway the top set in that rooting table regarding VE over the engine speed range, despite the Z4-type set (RSP IM modified, Z4-type cams) can be almost at same level in some areas. I like your choice 🆙.

What do you reckon I will make with: Tegiwa intake, RRC IM, FD2 cams, FD2 pump, RDX injectors?
Depends on the healthiness of the engine. Compression and leak down test can indicate for better assumptions. You also should have a low mileage timing chain for proper result over the in future run mileage. Normally I recommend above 100k miles a new chain and TCT or after proving to have a perfect alignment of all timing chain markers.
 

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Engine is on it's 50k mileage and I bought it with 41k full Honda service history. I'm following my own 3-3.5k oil change interval with quality oils. As Im going to take the chain off during the pump swap - I'll replace chain and tensioner as well. Seen some chain stretch people having with 60k mileage, it won't hurt. Also will perform valve clearance myself first time and hope I won't cock it up.
 

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@LotusElise Yes, FD2 cams and TB.
I don’t have the means and knowledge to do RSP porting myself and managed to get a very good deal on RRC. Among of all stock manifolds RRC gives the most gains, especially at the top which is what we all want. I know someone who does RSP porting job, but it’s mate of my mates cousin so to speak - not tested, no dyno proofs etc.
I know regarding the header, but I’m planning to hit the track soon and don’t want to do it without buffled sump and pump. As I have to take everything off - makes sense to get everything done in one go and forget about it.
I will go with the custom 4-2-1 exhaust manifold from Solid Fabrications and most probably Fujitsubo Powergetter. I know it’s a bit more restrictive catback than 3”, but it sounds amazing and this is my only/family car and I will try to stay civilised as much as I can.
MAF sensor will stay (I’ve got Tegiwa closed intake with driven crazy scoopin) and the mapping itself will be done by Paul West - he is a reputable person on the Honda scene in UK.
View attachment 102917
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@KBuilt I will try to get to RRC as close as possible and staying OEM. Imo fn2 is down on power and should be at least 225 from factory.
@LotusElise are the k20z1 camshafts comparable to these, the RRC cams?
 

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Arouse the DAMPFHAMMER!
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@LotusElise are the k20z1 camshafts comparable to these, the RRC cams?
Yes, the K20A cams have the part #1411(2)0-PRC-000 till #1411(2)0-PRC-020. The K20Z1 cams have the 4th revision of them, having the #1411(2)0-PRC-030. Member 6sd_EK measured them and the are profile wise on spec with the 000 to 020, just centerline has a slight deviation.
 

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Engine is on it's 50k mileage and I bought it with 41k full Honda service history. I'm following my own 3-3.5k oil change interval with quality oils....
Sounds good. A compression and leakdown test would anyway my recommendation.
 

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Yes, the K20A cams have the part #1411(2)0-PRC-000 till #1411(2)0-PRC-020. The K20Z1 cams have the 4th revision of them, having the #1411(2)0-PRC-030. Member 6sd_EK measured them and the are profile wise on spec with the 000 to 020, just centerline has a slight deviation.
From what I gathered online those cams are the same as JDM DC5,EP3, CL9, FD2 and USDM 04-06 DC5. When I checked FD2 parts catalog those cams were listed as oem.

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Would like your advice on oil temp/pressure installation method. I’ve read that sandwich plates could be not ideal or it depends on brand/quality on the unit?
What do you think about k-tuned adapter - will it be reliable enough to support above sensors plus oem sensor? I don’t want to wreck the threads on the block.

 

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Arouse the DAMPFHAMMER!
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Would like your advice on oil temp/pressure installation method.
As for the pressure sensor, it can be placed at the stock oil pressure switch or on a pre-filter location. As for the temperature sensor it should be placed where oil passes directly the sensor. A remote place like the KTuned adapter isn't a good method, as it is falsifies the measurement.
 

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Will it send an error if I disconnect oem pressure sensor?

I've seen on Toda oil pan additional port that potentially could be used for the temp sensor... Is it good idea to make one out of fn2 oil pan?
 

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@LotusElise Would you say it make sense to get oil temp/pressure and afr gauges for my application of around 240+hp max build on oem parts? It's my daily, but I will be going to the track few times a year, so is it worth it?
 

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@LotusElise Would you say it make sense to get oil temp/pressure and afr gauges for my application of around 240+hp max build on oem parts? It's my daily, but I will be going to the track few times a year, so is it worth it?
Yes, it is worth it. Whenever you have the chance to get to know your heartbeat rate once you do series training for the runner season, you will measure it during training. Same here, once you know it you know more about the healt status about your engine. For me it is a duty, not a question. Others may think differently.

Will it send an error if I disconnect oem pressure sensor?
Yes, but solutions or way better alternatives are available: Vtec Oil Pressure Sensor/Kpro/JDM K20A problem. | Honda / Acura K20a K24a Engine Forum

I've seen on Toda oil pan additional port that potentially could be used for the temp sensor... Is it good idea to make one out of fn2 oil pan?
I've used this location on my last K-swap, better then nothing, but the delay in temperature due to the high oil volume is around several minutes not just 10 s a proper position would give. Better than no temperature info in any way :).
 
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