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Discussion Starter #1
Hey guys,

So I have been doing everything myself on this engine build so far...but now I have hit a straight up wall! Here's what I've got going now:

  • K24A1 Block
  • K24A1 Crankshaft
  • RBB Acura TSX Cyl Head from K24A2
Here's what I'm aiming for:
  • To learn-- MOST IMPORTANTLY
  • To build a reliable K24 frank
  • To make around 250 whp or more
Here are the parts I'm going to try to get:
  • Stage 2 cams from Skunk2, or KME, or Kelford, or etc
  • 12.3:1 Mahle Pistons in 2618 forged alloy
  • I-beam con-rods
  • OEM color-coded honda bearings
  • K20A2 oil pump with everything needed for it to work
I'm at the stage where I've got everything disassembled basically. I got the K24A1 block for mad cheap and I got the TSX head for an extremely cheap price as well! So what I set out to do was do it all on a budget.

Here are some pics of the beast: :)

Here's a pic of the motor chilling:



Here's a pic of the K24A1 oil pump:



Here's a pic of the girdle holding in the crank:



Here's a pic of the old K24A1 cyl head:



Here's the new K24A2 RBB-1 cyl head:



And here's a pic of me trying to blueprint for runout :fuuu::



This is where I'm stuck. It costs A TON to build a motor correctly, and I'm aware of that, however I'm also extremely detail and technically-oriented. So, I tried blueprinting myself.

However there are two things currently in my way of solving said problems:

  1. I am afraid that if I blueprint myself then the motor will not be put together correctly
  2. I am short on money because I'm a college student so getting a shop to blueprint for me is not optimal but is always an option
  3. Good blueprinting tools are VERY expensive
And because I cannot correctly blueprint the engine on my own as of now, I am confused on how I will determine a few things WITHOUT spending a lot of money. For example:

  • How do I know if I need to turn my crank?
  • How do I need to know if my cylinders need to be bored or rehoned
  • How do I know if I need new crank journal bearings?
  • How do I know if my cylinder head and cylinder block are not warped?
All I am coming here for is to discuss my build-- where I'm at, how far I've come, what I'm excited for, and to gain knowledge from other people's builds.

And if I can get ANY contribution from you guys-- suggestions, thoughts, opinions, facts, I am NOT a sensitive guy when it comes to the truth.

So I appreciate you guys checking out my thread. Let's chat!

:)
 

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If 250 hp is your goal, then don't bother building the short block (especially if you are short on both experience and money). You can make 250 pretty easy with an intake, RBC, Type S oil pump, and a decent header with 3" exhaust. A DIY small port job on the TSX head to clean up casting seams would also be a good idea since the head is already apart.

You should also start a build thread in the RSX/EP3/EM2 subforum so you can get ongoing help with your project.
 

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I agree with BnD, no need to tear the engine apart if it was running fine prior. You can meet your goals with good bolt-on parts, cams, and a tune.

If you don't have a copy of the FSM, I recommend downloading it from the DIY/FAQ link in my signature.

Let me know where you would like the thread moved to :up:
 

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I agree with that which has already been posted. If you have access to a mill with a riser plate, you can check to see if the block is warped or not, by using an indicator in the collet. You can also check the head, as well. You'll want to make sure the mill is trammed in first, though. ;)
 

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The bottom ends are quite stout. The design of the motors is very good, especially in the bottom end/block. If there is any issue with the head, whether it is warped or shows signs of overheating, then I would tear it apart and inspect.
 

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Discussion Starter #7
If 250 hp is your goal, then don't bother building the short block (especially if you are short on both experience and money). You can make 250 pretty easy with an intake, RBC, Type S oil pump, and a decent header with 3" exhaust. A DIY small port job on the TSX head to clean up casting seams would also be a good idea since the head is already apart.

You should also start a build thread in the RSX/EP3/EM2 subforum so you can get ongoing help with your project.
Those are some really good suggestions. At one point I was considering doing TSX 11.0:1 piston from the newer generation k24a2 with the same rods but being that this will be going into a daily i was worried that the lack of oil squirters may hurt the pistons. I know they're often blocked off but Im an engineer so Im always trying to design or build things with an extra layer of protection.

This is why i was considering using a less expansive alloy on a forged piston with a high CR. But if I can reach my goals without them I will definitely reconsider.

Also I haven't made a build thread yet because my car isn't very crazy in terms of mods...just coilovers, wheels, i/h/e...

I also didn't post this in engine building because I was asking for suggestions. from what i understand it is best to ask for suggestions in a lounge section.

I agree with BnD, no need to tear the engine apart if it was running fine prior. You can meet your goals with good bolt-on parts, cams, and a tune.*

If you don't have a copy of the FSM, I recommend downloading it from the DIY/FAQ link in my signature.*

Let me know where you would like the thread moved to*
Okay, thanks Signalpuke. The thing is I have already tore the engine apart to inspect it.because I bought it from a guy who said it was running, but I never actually saw it running. Plus I fired it would be a great opportunity to learn about motors hands on.

I don't know what the FSM is! :eek:

And again thanks bud. I will put together some pics, make a build thread and link them to.this thread :) no need to sweat it.

I agree with that which has already been posted. If you have access to a mill with a riser plate, you can check to see if the block is warped or not, by using an indicator in the collet. You can also check the head, as well. You'll want to make sure the mill is trammed in first, though. ;)
Thanks Matt!! I have a mill at my chemical plant. I may ask the maintenance mgr if he is cool w me using it...but I already have a straight edge...its just an eBay one so I am not sure I trust it!

The only reason I was checking for warpage anyway is because the maintenance manual for the TSX already says to do so...so if it is not necessary perhaps I won't even worry too much about it. BTW I used the straight edge.on my new head already...it is in OEM spec :)

How is your EM2 doing? Glad I found you on FB because that jawn is pretty badass. :new_slayer:
 

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Disclaimer: Just my opinion :)

I would think most (if not all) stg2 cams would need to rev up higher than any stock K24 (non-A2) bottom end wants to rev. I know guys that rev the piss out of such bottom ends and get good power but, for DD reliability, they wont last. I figure they're safe to 7000-7200 rpm....maybe 7500 rev limit but that's pushing it.

I'm learning about a higher comp K24 bottom end builds right now. But it would be race only. It's expensive. Like turbo expensive. And, like 10dsbrennan said, quality stretch gauges and low lb torque wrenches can get up there in cost. ERL blocks are pricey.
 

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idk what your budget is but if the blcok and head are in decent shape it should not cost a arm and a leg to do what you are wanting. my local machine shop charges $120 to bore/hone block to match pistons. and for less than $100 will check crank and mic rod bearing journals/rods and determine whaat size bearings would be needed. if no damage to crank you can most likely go back with same color oem main bearings. you should have no issue with reassembling the motor with the fsm(factory service manual/helms). its in the faq section for free. download it, it will be your best friend during this process. also if on a budget and want a cheaper piston than mahle try the supertechs as they are very similar and can be had for $400-450 shipped. hit up [email protected] on here he has good prices.
 

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Discussion Starter #10 (Edited)
Disclaimer: Just my opinion

I would think most (if not all) stg2 cams would need to rev up higher than any stock K24 (non-A2) bottom end wants to rev. I know guys that rev the piss out of such bottom ends and get good power but, for DD reliability, they wont last. I figure they're safe to 7000-7200 rpm....maybe 7500 rev limit but that's pushing it.

I'm learning about a higher comp K24 bottom end builds right now. But it would be race only. It's expensive. Like turbo expensive. And, like 10dsbrennan said, quality stretch gauges and low lb torque wrenches can get up there in cost. ERL blocks are pricey.
I can't find the thread on CRSX, but I remember people with K20's and bolt-ons in Type-S's reaching 230-240 whp on stage 2 Kelford Cams. This is with a slightly raised rev limit.

Most think you HAVE to rev super high to make power, but it depends on where in the band you want power and also your compression and cams. I think I would be fine running OEM internals on a K24 block with those cams considering people usually raise OEM rev limit 500 or 600 RPM from stock on these motors with stock inernals and no issues.

http://www.k20a.org/forum/showthread.php?t=78617

That's a good thread talking about this^

Only reason I wanted to do forged was for INCREASED reliability and added reassurance...it CAN be done on stock internals though based on what I've read.

idk what your budget is but if the blcok and head are in decent shape it should not cost a arm and a leg to do what you are wanting.

my local machine shop charges $120 to bore/hone block to match pistons. and for less than $100 will check crank and mic rod bearing journals/rods and determine whaat size bearings would be needed.

if no damage to crank you can most likely go back with same color oem main bearings. you should have no issue with reassembling the motor with the fsm(factory service manual/helms). its in the faq section for free. download it, it will be your best friend during this process.

also if on a budget and want a cheaper piston than mahle try the supertechs as they are very similar and can be had for $400-450 shipped. hit up [email protected] on here he has good prices.
This is some super good info bro! :up:

I think a lot of the blueprinting had me sweating it. However, I do have a question-- how do you determine which color to use based on rod-crank and crank-journal clearance?

In the FSM, it just tells you to use the codes written on the crank and block and crank and rods. Then it tells you if your plasti gauge reads wrong to test the next larger or smaller color bearing.

Seems like a lot of work just to pick a bearing :fuuu:

If the Supertechs come in 2618 I am down for them...but I have only seen Mahle in this alloy..plus I can get a good deal on most parts from my friend :)
 

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A quality stretch gauge will help plasti-gauge read more accurately. I wouldn't do it with a torque wrench but guys do. I wouldn't go by stock Honda color codes unless it was a refresh build with same crank/rods. Shot Peen the rods will let you rev a tiny bit higher.

What I mean about those Kelford B's on a stock non-A2 K24....those cams want to make power at a power band that is too high for those motors. The power band would be shifted too far right. You could still use them but power would be left on the table or you'd risk grenading the motor. I figure Z1 cams would benefit such a set up better

My stock K20A w/RBC IM is 227whp and almost 165tq. I figure it's about 285-ish to the wheels.
 

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Discussion Starter #12 (Edited)
What I mean about those Kelford B's on a stock non-A2 K24....You could still use them but power would be left on the table or you'd risk grenading the motor.
Yeah, it's been done before without problems, but like you said it's a risk and I'm not sure how willing I am to take the risk.

CRIP, do you think I should get my crank checked for straightness and my block main journals checked for straightness as well? Crank turned smoothly while motor was together, but perhaps it's a good level of protection?
 

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everyone has their own way of doing it, but es i would have the machine shop check my crank/crank bearings and rod journals with the rods i am planning on running. you can do it with plasigage but they have much more precise tools to do that with.

if block was good you should have no issue with running same main bearings, the should be letters/number combonations stamped on the block which will tell you what bearings it has. can not recall off top of my head but should explain it in the service manual. be awhile since i put last motor together.

tons of ppl have had great exp. with the supertech pistons and that will save you $100-200 on pistons. i have raan eagle rods in couple motors and never had a issue(i know they are china rods but never failed me). give the rod to machine shop with the page showing the rod bearing thickness' and the should be able to get you the right bearing sizes/colors.

if machine shop does the leg work you should have no issues assembling the motor with the fsm and it lasting. i was scared shitless my first motor i built but if you do not just in feet first you will never learn.
 

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Discussion Starter #14
Okay thanks bud. You really opened up my eyes to possibilities of how to build a motor which is exactly why I started this thread...

I think I may be stopped before I even get moving again though because I was blueprinting my crankshaft for runout tonight when I found these:







Are these casting marks or is my block cracked! :(
 

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quick way to do a budget motor in a hurry. it's not rocket science. it's actually easy.

look for bad stuff. (terrible marks in bores, bearing damage, stripped threads)
if ok proceed
grab .5mm over pistons, acl race rod bearings, and what ever brand h beam.
look at wear on mains
if really nice bearings remove and mark location removed from.
bag and save them.
take block and pistons to machine shop for bore job.
make sure wristpin pin fit is nice on rods.
mark pins to rods you tested them in.
if they don't fit nice, take to machine shop.
pick up block at machine shop.
file rings.
put pins in.
clean, reinstall, and lube mains and crank.
spin crank.
drop in pistons and rods.
plastigauge rods.
should be fine.
lube and reinstall.
done...yay!
go run 14's 10's 7's whatever
I do it in parking lots or trailers all the time.
 

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no problem! you can see a lot with just how things wore or didn't wear in the motor. In all honesty starting with a solid undamaged block and crank is more important than measuring. if a rod bearing gets beat up a little from detonation or a miss shift it's easy to miss the damage measuring the crank. the damage area is sooo small. if you see it in the bearing or lack of tension on rod bolts then you know it's there. Moral of the story is don't fix what isn't broken and sometimes (actually most of the time) broken stuff should go in the dumpster.

by all means keep asking random stuff. it's how you learn! there's some great mechanics in here to help. after doing this stuff over and over and over you just get a "feel" for things. I've watched many people start off not knowing anything about cars go on to do incredible things.

btw there's 2 great videos I've seen on engine building awhile back that are worth checking out
one is from jeff at evans-tuning
the other is from gary kubo from world racing
 

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Discussion Starter #20
Wise words on how you develop a "feel" because that is exactly what I'm trying to do :up:

I have been taking a large amount of time to overanalyze the crap out of this build and I intend to keep doing so if it helps me to build a reliable and fun-to-drive motor for my RSX :)

I will have to check out the Kubo video...I've already seen the Evans Tuning video. It was super informative.
 
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