1975 Ke20 "rally Rolla"

[altezzaclub]

and i have to measure the cc tomorow... dunno how but I'm gonna try

Plastic sheet between 1mm and 3mm thick is easy to find, it just has to be big anough to cover one cyl. drill a 5mm hole through it & seal it with grease around the edge.

 

25ml graduated burette or pipette is best to measure the liquid, use kero or turps or similar. Each combustion chamber will take around 30cc,so you run in 25cc the refil the burette for the rest. Burettes have a tap on the bottom, so are expensive. A 25cc graduated pipette will also do, you release drops by turning it with your finger over the top.

 

Use the porting tool to unshroud around the valves, especially the inlets, taking them out to within a mm of the head gasket mark. Make them all the volume of the largest unless you get keen and just make them all as big as is needed to give the valve breathing room. Then skim the head to get the compression back up.

 

You calculate the amount to skim off by measuring the area with graph paper, then working out what size "column" to take off to get the ratio you want. Everythin else like cylinder volume and head gasket volume is known and fixed. Post up here if you want a lecture on it...

[SM Hunter]

i tred my best... i filled it up with kerosene then sucked it up with a thingy and put in in a glass and brough it home.. measured 27milli liters... forgot to do the paper thingy... :(

after i did that i removed all the valves..

cleaning up and i did widen them a bit... mostly the exhausts

cleaned up

the "fine" grinding paste..

Re-Grinding = done

 

the manifold is almost stright, its just a little bit off...

 

here is a pic of when i checked the ML of the chamber.. its a little bit higher on one side ... so i think 27ml is a bit under what it really is, i migh have spilled while getting it out there aswell? i don't know?

now how much do you thing i should shave off. i think the head is orignal..?

Edited November 29, 2014 by SM Hunter

[altezzaclub]

ooohh...nice workshop!

 

27ml is less than I expect, unless its a 3K head (or one of the 5K variants). The sheet of plastic makes it much more accurate as it fill up evenly to the hole you make in it.

 

My 4K had 31cc and the graph paper added up to 30sqcm.

 

So for me-

Head volume 31ml

Gasket volume = Pi X radius X radius X thickness= 3.14x3.95x3.95x0.15= 7.35ml

Cylinder volume = 322ml

 

compression ratio 322+31+7.35 to 31+7.35 which is 9.4 to 1.

 

Skim 1mm off, you will remove (chamber area X 0.1)ml whch is 30Sqcmx0.1=3ml

 

Now you have 322+(31-3)+7.35 to (31-3)+7.35 which is 9.86 to 1.

 

So you can see how you use the head area from the graph paper to calculate how much to skim off to give you any compression ratio.

 

If you really have 27ml in the chamber your figures would be 322+27+7.35 to 27+7.35, which is 10.4 to 1, before you skim it!

 

The valves could do with a spin in the drill with sandpaper to clean all the carbon off the back of them. Keep the seats nice and cleanly cut like you have them. Think of how small the gap is between the back of the valve and the edge of the valve seat, and all your airflow has to go through that few mm. So anything to make the back of the valve smooth and polished helps. That is why they cut valve seats in three or more angles, to maximise that flow through the narrowest gap.

 

If you look at a cam graph you realise that most airflow goes through a much smaller gap than at max lift, as the valve is only at max lift for a millisecond. Its why unshrouding the valve area by cutting back the combustion chamber wall also helps, if you look at an inlet in the head you see most of the airflow area has a wall right in front of it. Changing that is the major advantage of 4valve heads.

 

Here's some random reading I found loking for a diagram-

http://www.s26261265...drews/heads.htm

 

You can see how the area close around the valve does not flow as cleanly as the open side. The combustion chamber wall blocks it, and then the cylinder wall is too close.

 

 

Its a black art! In the '70s Ford found some of their heads straight off the production line flowed better than highly modified ones they had spents hours porting.

[SM Hunter]

ahhh thanks for the numbers! but mine is a 3k flat piston... the numbers from a 4k would not be correct due to larger bore? or will it

the 27ml probly is not right, but i could not find anything to meassure with... i just had a thiny to suck it out of the head with--> i probly did not get all of the kero out of the head--> then i put it in a glass and i probly did not get all of the kero out of the sucker thingy....

 

I'm not sure i got the time to go to the workshop today since i got a math exam thingy tomorow :(

Edited November 30, 2014 by SM Hunter

[SM Hunter]

anyways, dragged my Carina home from the Fields today

But the 1965 Volvo Buster 400 just could not do it

anyways, heres my 1100 GSX-R carbs, Mikuni Flatslids anyones who knows how big they are?

ill only need to make manifolds to suits the K serie engines

you guys think theese will work with my 1,2?

Dad used to sell Arctic-cat snowmobiles( with Suzuki engines) so he got loads of Mikuni stuff lying arrund :)

Edited November 30, 2014 by SM Hunter

[altezzaclub]

mine is a 3k flat piston

OK, you just change the 4K stroke in the maths to your 3K stroke. So the cylinder volume is smaller, but the head gasket volume & the combustion chamber area stays the same. I would expect the combustion chamber volume to be about 27ml, I think that is what Richard got for his 3K head on the 345K we built. However, his 3K head had the whole combustion chamber sunk into the head a mm or so, giving a circular ridge all the way around where the head gasket sits. Maybe someone else on here can explain that.

 

I reckon 0.75mm off will give you 10.0 to 1 but you can check that using your cyl volume of 291ml and chamber of 27ml.

 

You can measure the Mikuni's diameter with calipers. They'll be somewhere between 36 and 40mm I expect. See the one slide that is not sitting equal with the others? Make sure they all move up and down in synchrony. Best thing is, search the net for everything you can, or find a mechanic locally who knows about them, and strip them down & clean them. Check the diaphrams and gaskets for leaks, the jets for dirt and see what can be lubricated..

 

The size of the carb exit into the manifold will tell you the manifold tube size to use, and that should match up with your inlet ports on the head. I'm sure they will work on your K motor, they just won't get fully exercised! You will need some curved manifold tube to allow for the sloping K motor, you want to end up with the Mikuni fuel bowl horizontal.

 

Grab a mixture display meter if you come across one, I found it invaluable in setting up the twin SUs. They use needles like your Mikunis, so you can sand the needles to change their shape in different rev ranges. If you get one, have a nut for an oxy sensor welded into your extractors before you fit them. The option is a dyno for air/fuel mixture readings, but that might take quite a few runs and get expensive.

[SM Hunter]

Ahh ill do some math, if i end up with the same as you ill shave off about 0.75 then :)

you sure about the carbs sitting horizontally? iv seen severals that got bike carbs at 45 degrees etc.. but ill do some research on my carbs to find out :)

yeah a Air/Fuel meter is a must! I'm familiar with that, i tuned my brothers S13( ca18det, Forged rods, ported head, 2x exhaust cams, 1000cc injectors( for future e85) t28 turbo, 2,5" exhaust, front mounted intercooler and z32 air mass meter and oil cooler) i we made over 300hp judging by the amout of force pushung you back in the seat even at 150km/h.. Tuned it with NisTune and a air/fuel meter.. I know a carb car is worse but i is possible :)

 

the carbs sould be good, iv driven them 250kms on the fields :) pulls strong all the way from idle to valve float on the 2tc :)

had to stop the madness cause i broke the T50 :) soo I'm parting out the TA60 and hoping to put a overhauled drivetrain in my other ke20 one day :)

anyways here is a video, carbs sould be good, if not ill get some help by dad who knows Mikunis to rebuild them :)

he also thinks he got the stuff i need, jets etc :)

iv got some experience with my moped :) bought a 20$ china carb.. never should have done that :P

[altezzaclub]

Here is a picture of what your ports should look like! The 3K bigport picture.

http://www.rollaclub...400#entry691400

 

With this photo note the way the combustion chamber is sunk into the head a little, maybe a mm or so. There is that ridge running around where the head gasket sits. It makes me wonder if your head is a 3K that has been skimmed, or not a 3K but a 4K, as they are a flat head. Do the liquid measure again carefully and see what you get.

 

At least you have the Mikunis sorted, I thought your Dad would either know all about them or have a good mechanic locally. I think they sit with the seam of the float bowl horizontal, so the body still sticks upwards. I don't know how bad it is for mixture if they are at completely the wrong angle, but they were designed to be leaned over sideways and still work! This photo is from Tommy's car of the year- Anyway, find a set in a bike or something still factory-fitted and see how they hang.

 

There is another guy on here looking at Mikunis on a 2T, maybe you could sell him your manifold.

 

here's a set-

Edited December 1, 2014 by altezzaclub

[SM Hunter]

Whoho! i just fell in love with the Bigport head!

yeah i need to get hold of stuff to measure propperly this time!

yeah the manifold is for sale :)

 

anyways, original carb looks small..

Needs some porting

Snapped all fraking bolts

NEEEDS LOOOOTS OF PORTING

Very rough

Used a couppel of hours trying to match everything and get it "free flowing".. have to weld it up porpperly, iv just welded a bit here and there in case i had to take it apart...

and it ended up very close to my brake pump... ill try to get it further back :)

i love this!

Edited December 1, 2014 by SM Hunter

[altezzaclub]

That was quick! Looks good!

 

Can you make them shorter?? Pull 30mm out of the steel manifold and the rubber hoses so you get more room at the brake cylinder. Now I do see the disadvantage of left-hand drive.

 

Are you going to make a plate to cover the hole in the exhaust, and just weld it over the three bolts? Then braize around the edge to seal it. Another way would be to put a larger plate inside with 3 bolts welded to it, and a plate on top to clamp it and sandwich the manifold between the two. There may not be a flat surface inside for that to work. Of course the correct way is to drill out those three bolts a clean the threads up before replacing them, but that is always difficult to align. Mind you, the best way is to throw the original exhaust away and get extractors!

 

I am negotiating for a cam for you...

[SM Hunter]

yeah, the plan is to make them a bit shorter and maybe try to make a airfilter box or ill go quad filter :) had go get my head of the math exam so figured ut this was the best way :P

 

my plan with the exhaust hole is soak the bolts in rust remover for a coupple of days, then try to weld a bit larger nut to it and try to undo it.. if that doesent work ill be testing out your brillliant idea!

Yeah LHD Corolla with k enigine is a pain in the arse! inlet, exhaust, starter brake and steering all in the same place, for e.g a turbo setup i think you would have to uppright the engine.. :P

 

yeah really keen on a set of extractors but the chance of them not fitting is HUUUGE.... when the summer comes arround and i can gather some more money ill look arround for some.. i know of a Finish company who makes them for LHD cars :)

 

 

EDIT: How many HP do you guys think this engine will produce? should i invest in a hotter cam+ stiffer springs when I'm at it?

Edited December 1, 2014 by SM Hunter

[altezzaclub]

Can you make the extractors? Cut the same sort of plate you did for the inlets, weld a bar along it to hold it in shape like the Hurricanes have, and then tack-weld curves together to make the shape. I saw a guy doing just that for a V8 he put into an Altezza, he had a lot of short curves he mixed an matched then had it all welded up.

 

Here's what they look like

http://www.hurricaneheaders.com.au/hurricane/products_main.php?txt1=Headers%20/%20Manifolds%3Cbr%3E/%20Turbo%20Exhausts&txt2=Headers%20/%20Extractors&txt3=TOYOTA&txt4=COROLLA%20&txt5=4%20CYL&lvl1=1&lvl2=5&lvl3=29&lvl4=169&lvl5=1694#

 

https://www.bestmufflers.com/bshop/images/hu077st2.jpg

 

http://www.performanceexhaust.com.au/ebay/HU077ST_1.jpg

 

I've got an old set in the shed if you want detailed photos.

 

K motors don't produce horsepower, they just sound different!

[SM Hunter]

naah i don't want to make my own. ill just re-deseign one :) some time

Massive thanks to you Altezzaclub for all this help and hopefully a cam! this would not have been done without you!!! :thumbsup:

 

anyways.. Keep in mind I'm no welder... i'v had a 10 min guid by graddad but nothing more... + been rust welding all this Freaking car and build myself a "gocart" but i did not learn so much :P

started welding them up

and yeah, the middle pipe is freaking galvanized!!! I am never going to weld anything galvanized again!

must be free flowing when you can see out where the valve sits :)

perfect

some small adjustments and i got them like 3-4cm further back :D

moooar space

room here aswell

as all of you know, if you cut a pipe at an angle it looks like an egg afterwards... so my pipes did not fit my holes...

you can see the edge there.. a huge air block..

all 4 had these..

welded a bit inside there then grinded it back down

a bit more cleaning up and they are perfect!

lets just hope this is air proof... i just could not fit the weldder in between them so i had to do it this getto way..

Edited December 2, 2014 by SM Hunter

[altezzaclub]

Done! You can always smear them with some filler/adhesive if there are cracks. "No-more-nails" building adhesive or "Maniseal" exhaust sealant, they will fill tiny holes.

 

Welding galv steel is bad, that smoke from the zinc atttacks your nerves and kills them, so you get brain damage eventually. I think that has already happened to people who spend their life working on old cars when they could just go out and buy a newer one then spend better time watching TV.

 

Can you find a thin metal sheet to put under the carb and above the exhaust to act as a heat shieId? have a sheet of 1mm aluminium on mine to try and limit the heat from the extractors getting in and vapourising the fuel in the carbs. Also to stop fuel dripping on the exhaust when the carbs overflow.... SU carbs are kown for that problem, alhough this pair are good.

[SM Hunter]

yeah, iv been thinking about making a plate between the carb and extractor since i hav noticed everyone has one..

ohhh... ill turn on the fan the next time I'm welding galvanized shit, i freaking hate it anyways :P

 

ahhh filler is a genius idea! thanks! how hot do a inlet manifold get? is it so cold that i can use whatever i want? :) like silicone or something? :)