Aiden’s 521 V.2

[521aiden]

rebello said ka pistons and then to mill them down 8mm or so to have a true flattop forged piston that's actually obtainable.

[521aiden]

9 hours ago, datzenmike said:

 

There are dished Z20 pistons used on the 720 truck. Maybe what you saw.

 

N85 rods on an L20B/Z20 crankshaft only leaves 26.95mm for a pin height. Do you know the pin height on the DE pistons? I found 34mm which is the same as the KA24E. To fit you would need to mill 7mm from the tops. That's way over 1/4". Almost into the top ring land. Better check.

 

KA24E pistons on L20B/Z22 rods in bored to 89mm block works and makes a 2,300cc

 

 

 

 

 

if i could get my hands on a z22 crank i might do that but if I'm keeping the 2 liter crank I think ill stick with the long rod set up.

[Crashtd420]

On 4/9/2022 at 7:18 PM, 521aiden said:

rebello said ka pistons and then to mill them down 8mm or so to have a true flattop forged piston that's actually obtainable.

You could have a look at the wiseco website... 

I bought some L series pistons from them and didn't really have any options so I ended up using 9cc dome pistons, but apparently they will make custom pistons now.... 

Just need to supply them with the neccessary information....

Edited April 11, 2022 by Crashtd420

[datzenmike]

On 4/9/2022 at 4:18 PM, 521aiden said:

rebello said ka pistons and then to mill them down 8mm or so to have a true flattop forged piston that's actually obtainable.

 

 

Find out the pin height of the KA24DE pistons to be sure but the KA24E pistons are 2cc 'dish' and basically a flattop. Use with L20B rods and they fit an 89mm bore L20B/Z20/Z22 block. 

 

[521aiden]

what i did was i milled .078 off the top of my ka dished pistons which left me with -3.3cc dish and as far as pin height the z20e rods are 152.5mm the z20 pistons are 31.74mm my new ka pistons were originally 34mm, .078" comes out to 1.9812mm which leaves me with 32.198mm pistons, my deck height is 227.45 from stock and with that piston and rod combo ill be at 227.698mm or .248 above deck height or about .010" above and i'm running the kameari big bore 90.5mm head gasket that has a compressed thickness of 2mm to keep my compression reasonable at 9.5-10:1. porting my head today as per rebello trying to stay around 44ccs in the combustion chambers and then slightly over sized valves a lower lift cam for now to maintain street driving ill probably put a little more duration in it in the future and then i have the better flowing cast manifold dual dcoe 45s a goose neck 620 webber intake im going to port all new parts for my head and some other stuff

[521aiden]

On 4/11/2022 at 10:09 AM, Crashtd420 said:

You could have a look at the wiseco website... 

I bought some L series pistons from them and didn't really have any options so I ended up using 9cc dome pistons, but apparently they will make custom pistons now.... 

Just need to supply them with the neccessary information....

I actually did call nearly every piston maker the problem is they were backed up for months at a minimum shortest lead time i got was 10 weeks i think so i ended up getting some off the shelf forged supertech pistons and after milling them it was still cheaper than custom but not by much.

[521aiden]

also as far as displacement goes it will be 2140cc which is no stroker but its not small either

[datzenmike]

These must be DE pistons? if cutting 0.078" off and still having 3.3 dish? Why not just use KA24E pistons that only have 2.8cc dish to start with? 0.078" off the tops would make them flattops.

 

152.5mm rods

34mm - 1.982mm (0.078") = 32.0188mm* piston pin height. * this difference above the deck is practically negligible as far as compression goes.

43mm (L20B stroke 86/2=43)

 

adds to...

 

227.5188mm

 

227.45 - 227.5188 = 0.0688mm above the deck

 

Assuming crushed gasket thickness of 2mm, combustion chamber of 44cc, piston dish of 3.3cc and deck height above of 0.0.0688mm then the compression is 9.956

 

Swept cylinder volume is 2138.98cc

[521aiden]

mostly availability, if i had to choose now i’d probably do vg pistons instead 

[datzenmike]

No, you made the best choice.

[Stoffregen Motorsports]

17 hours ago, 521aiden said:

what i did was i milled .078 off the top of my ka dished pistons which left me with -3.3cc dish and as far as pin height the z20e rods are 152.5mm the z20 pistons are 31.74mm my new ka pistons were originally 34mm, .078" comes out to 1.9812mm which leaves me with 32.198mm pistons, my deck height is 227.45 from stock and with that piston and rod combo ill be at 227.698mm or .248 above deck height or about .010" above and i'm running the kameari big bore 90.5mm head gasket that has a compressed thickness of 2mm to keep my compression reasonable at 9.5-10:1. porting my head today as per rebello trying to stay around 44ccs in the combustion chambers and then slightly over sized valves a lower lift cam for now to maintain street driving ill probably put a little more duration in it in the future and then i have the better flowing cast manifold dual dcoe 45s a goose neck 620 webber intake im going to port all new parts for my head and some other stuff

Perfect. Yes, those have to be the DE pistons. They work great when cut down.

 

Curious, did you cut them in a lathe or on a mill?

[521aiden]

On 1/19/2023 at 7:55 AM, Stoffregen Motorsports said:

Perfect. Yes, those have to be the DE pistons. They work great when cut down.

 

Curious, did you cut them in a lathe or on a mill?

yes they are de pistons I had them cut down by grc precision machine in east county San Diego im pretty sure its just a specific piston chuck for his lathe.

[521aiden]

little update, my bottom end is back from machine shop, had the following done:

clean and mag block

bore/ hone cylinders

line hone mains (were slightly out of round with arp main studs)

surface block and timing cover 

new freeze plugs 

crank polish 

rod sizing and check with arp bolts 

full dynamic balance 

and surfaced my flywheel 

also dropped off my head to get machines they’re going to get me down to my desired 44ccs and check for warp put in new seats and possibly guides. 

 

now my parts list consists of:

spark plug wires, new hotter plugs, a couple gaskets 

 

if anyone has any advice on what plug to run (preferably denso) i’m open to suggestions not really educated on heat ranges and such. anyway thanks for following along and I should have more updates and some pictures as everything comes together!

[Stoffregen Motorsports]

NGK B6ES is always a good place to start. Some guys will recommend BP#ES plugs, but the projected tip on that plug makes pinging more of an issue.

[Crashtd420]

21 hours ago, Stoffregen Motorsports said:

NGK B6ES is always a good place to start. Some guys will recommend BP#ES plugs, but the projected tip on that plug makes pinging more of an issue.

I would agree, I'll add one more fact...

If you want or need a slightly larger gap go with the

B6es-11... they are set with a .042-.044 gap....

Also buy at the parts store, to many counterfeits out there on Amazon and ebay.... not sure if other online places are an issue like rockauto....

[Stoffregen Motorsports]

Good call.

3 hours ago, Crashtd420 said:

I would agree, I'll add one more fact...

If you want or need a slightly larger gap go with the

B6es-11... they are set with a .042-.044 gap....

Also buy at the parts store, to many counterfeits out there on Amazon and ebay.... not sure if other online places are an issue like rockauto....

 

[521aiden]

update:

I have been piecing the short block together over the last few days all the tolerance have been on the tighter end of the threshold according to my books so that’s good. After getting pistons in I was able to get a decent estimate of how much material has been taken off my block surface with my estimated ~.016” off (used calipers will probably break out the dial indicator when the bottom end is finished) i calculated cr at 10.29:1 which should work just fine. Head got milled .014” brining my massaged combustion chambers back to 44cc’s +/- .25cc’s also new 2mm os steel intake valve seats fitted and valve job with the new si valves. did a tiny bit more smoothing on my ports transitions and bowls now it’s good for assembly!

it took me a few days to track down keepers everyone I asked said they use originals which is fine by me except I got my current head bare and I didn’t want to canibalize my other completes for something so cheap. my machinist had an ancient supplier catalog that listed them and still carry’s them so that’s sorted now. also ordered some arp stainless studs definitely unnecessary but shouldn’t have any in/ex stud problems in the future. have the original style spring shims to keep them from marring the head on order from rebello cause again bare head hoping those ship out soon other than that a few little pieces left, just started the dive on my carb tuning education should be up to speed by the time I need to break in the engine i’ll show off my custom cam when I get it it’s extra pretty! 😉

 

that’s pretty much it for now shooting for a long block in the next week but trying to take it slow and be thorough hard to devote a lot of time between school work and other car projects but i’ll get there.

 

thanks for following along guys 

Edited March 11, 2023 by 521aiden

[521aiden]

[Stoffregen Motorsports]

Looks good.

 

Have you measured the piston deck height yet?

[521aiden]

1 hour ago, Stoffregen Motorsports said:

Looks good.

 

Have you measured the piston deck height yet?

yes, I threw the dial indicator on it came out to .012” above deck 10.13:1 actual static comp

[Stoffregen Motorsports]

Perfect.

[521aiden]

Not gone just busy! I've had lots to do lately three other project cars, parts holdups working with my 19 yo budget and college finals and work pulling me out of the garage but I am now back on track and making progress really hoping to get her back in the car and driving in the next few weeks! Engine doesn't look much different but it now has a head gasket, oil pan and pan support bracket, timing cover, timing gears and my kameari tensioner, an assembled head, arp head studs, and awaiting oil spray bar mod my cam to come back and timing gear. Ordered some 10w-40 Driven break-in Oil  and their high zinc "hot rod" for first oil change, Painted over my spray paint job from 10th grade with a single stage enamel in the stock green. My dad Patched the fiberglass repair the PO used to close the hole a rotten battery made in my passenger fenderwell, while prepping for paint I noticed weird globs of bondo near the master cylinders which happened to be covering up a hack job of covering up the E-brake completely severed from the firewall the spot-welded Sheetmetal tab was ripped out in a rectangle and recessed ~1.5" inside of the cab, after lots of pounding and tac welds my dad flushed that up too. Took a stab at rebuilding my "ready to go" 45 dcoe 152gs and doing a basic gasket refresh but when i opened them up they were chalk full of sawdust and corrosion, after multiple bottles of carb cleaner, soaking in a gallon of berrymans carb solution and lots of scrubbing brushing washing and wiping those are now, Hopefully good to go. other than that getting ready to play with lash pads in the next few days when I get my cam and then bolting on my 32/36 dgv and stock ex manifold for simplicity on break in going to swap to dcoes and a SW motorsport tri-y header that Stewart is sending me with the collector tube left un welded so I can play with orientation for torsion bars. putting my matchbox back in on first start but I also have a Lumenition kit and ign box that I am planning on swapping in retrofitted onto a Single point Hitachi distributor I've heard good things and I think itll be a little better at high rpm but not much info on them outside of Australia and Japan if that backfires I stil have the Matchbox so Im not too worried about that.

 

here's some pics and always, any adivice is appreciated and thanks everyone for the likes and looking through my Thread!

kameari00941.webp kameari00941 (1).webp

[Stoffregen Motorsports]

Get an ultrasonic cleaner. That crud in the carb can clog up the deepest parts of the carb and a heated ultrasonic cleaner is going to be the only way to get them usable again.

 

Motor looks good. WHo built the head?

[521aiden]

On 5/15/2023 at 10:33 AM, Stoffregen Motorsports said:

Get an ultrasonic cleaner. That crud in the carb can clog up the deepest parts of the carb and a heated ultrasonic cleaner is going to be the only way to get them usable again.

 

Motor looks good. WHo built the head?

looked at ultrasonics and ended up just going the more involved way i’ve got a few sets of carb cleaning tools and i’ve made sure every single hole is free of the crust and it’s been as thoroughly cleaned as possibly without the ultrasonic i’m breaking the engine in on the dgv so if it needs more work i’ll be able to tear them back down if i need to. 

 

head assembly and porting was me the valve job and surfacing was by GRC precision machine in san diego Gary is a the owner and a great machinist but he doesn’t seem to take much work on. He took my stuff because my boss asked him if he would help me out with it.

[521aiden]

went through a bunch of rocker arms and found two sets of four for intake and exhaust with pad heights within +/-.0005” of each other  and then I ground down where spring retainers usually interfere with the rockers on high lift cams a bit to get them as close as I could on tip weight  but avoiding taking out any significant material mostly cleaning up the casting lines and such on the heavy ones. did a wipe test and the 195 lash pads I started with and as I assumed are short but I had free access to them so I threw them in to check Just ordered some 230s, 240s and 250s base circles are around 1.06”-1.075 between intake and exhaust I think it’s on the third regrind so that’s why the small base but with my math that puts me at ~230-240 getting the 250s just as backups don't Th ink you can have too many sizes of lashpads. My ati balancer went on much easier than I thought it would I have an Oem Ka bolt otw from my measurements the L4 ati balancer on a 2l crank calls for right around 54 mm overall shank length between the extra thick kameari washer and my crank snout depth and the ka is 53mm so it’ll either be perfect or i’ll have to trim just a tiny bit off the bottom to avoid bottoming out . I have a kameari chromoly bolt and washer but the washer doesn’t fit and is going to require .0120” off of the diameter so .060 off all the way around t cited to try and cut that hardened steel as for the bolt it is right at 47mm iirc so I’ll have some options if the ka bolt isn’t a bolt on just want to avoid any balancer problems especially with the infamous crank bolt loosening thing that the Z guys talk about.