That’s a little of discussion … the cams will it be better, won’t it be better? Today my head is polished and ported, will it be the same? can it be used?
Despite having a stroke of just over 90mm, can revs up to 7500 rpm? It will be a lot?
This is the question! However I think if the internals are balanced correctly it should be ok… Also the bore is the same as the K3, is it possible to fit your high compression pistons?
I was told once by a Malaysian that you can run
K3 Block with 3SZ crank, rods and pistons and no further modifcations, this will alter the capacity of the engine to 1.5 litres however it also alters the stroke so peak power is now somewhere around 5000rpm and it won’t rev much harder.
again, advise from a Malaysian so take it with a pinch of salt.
It makes sense, if the bore is the same, then surely it’s the longer stroke that gives the 3SZ the 1.5L capacity over the K3VE 1.3L. Where it obtains that additional stroke (crank,rod) should be irrelevant if you swap over all of those items. The longer stroke then reduces some of the high-rev ability, which is what we see in the various specs.
It appears to be the piston shape in the K3’s that change the compression to either the low compression of the VET through to the high compression of the VE2. You can see in the earlier images, the high compression pistons here protrude more into the combustion chamber and feature cut-outs for all valves. Some general “internet reading” seems to imply that high-compression pistons in this manner separate the combustion chamber into two halves and isn’t the greatest for a complete/proper burn. To what degree is always hard to tell.
The 3SZ is the better flowing heads, K3VE2 cams are better - so they’re sorted.
The next best option as you said, was transpose the 3sz crank/rod assembly and put either VE2 or the 12.5:1 Hi-Comp pistons in to raise the compression. Using the 12.5:1 pistons with the longer stroke may not impact the combustion chamber as much in this way.
You might be able to get some extra revs via balancing etc, but the piston speed will be higher in the longer stroke option.
*Feel free to ignore the above, it’s not based on any significant experience. Just theorizing.
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hahahah I like what you put on “Feel free to ignore the above” but honestly it’s quite the opposite … basically I also theorize, much of what I do in my car is based on the advice of this forum. I’m sorry to be so hesitant but believe me that I am very happy with the forum, although I don’t participate as much as i would like (maybe it’s because by my poor english). (google helps i know)
There is an option that has not been touched and is to keep the engine, perhaps with stock pistons (high compression are prohibited) and designing an intake, cams perhaps. I don’t know how much more can be obtained but the problem of not being able to revs it would no longer exist. For last an advantage of weight also i can gain…
sad to see failure so early
but seems the Malaysian piston shop pistons are very very un reliable
big question with the engine choices is firstly how much you want to adjust with the electronics?
because is your ecu able to be custom wired?
changing to 3sz is a different type of loom
other is have you considered a chassis swap?
going to mira conversion will save you approx 100kg straight away
i haven’t seen many 3sz working well
but swapping their head onto k3 seems a good option
it seems clear of the reliable race engines i’ve seen that the k3 bottom end is very good if kept with factory parts - pauter rods seem quality and i know some piston manufacturers [actual manufacturers not sold out of you know where versions] are starting to do high compression versions. but to make the most out of these you need decent ECU options or not worth the money
sick of reading of people thinking they’re putting improved parts in, but spending money with Malaysian suppliers who have no idea what they’re doing!
all good point’s but I think he wont be able to go the L7 option as I imagine they would be quite rare in his part of the world. ( I may be wrong ofcoarse 
)
Perhaps the 4AFE is the best option?
Highest capacity allowed, more torque over K3.
A quick read implies 4AGE blue top pistons fit and raise compression. Then the other usual N/A tuning of intake/exhaust/cams/headwork - which you seem to have access to the tooling required to improve these aspects. Likewise with engine management…
Would love to see the K3/SZ combo work, but you’re still giving up a valuable 100cc to other 1600’s. From the video, torque out of the corner before the longer straight seems to be a big downfall. Though I’m sure this engine change will have many problems to overcome as it either hasn’t been done or isn’t very common.
4age conversion works
then you could convert it to 1.9L
but given budget for even factory replacement parts was a stretch then frankly like many it’s just all talk for now
fresh k3 parts and a proper tune with a proper computer and it will be a great package
i’ve helped a few locals in <1.6L class and they’re front runners with effectively a blueprinted stock engine and good tune and close ratio gearbox
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4age conversion works
then you could convert it to 1.9L
Sadly the 4AGE is ruled out due to not being a sold engine in Chile, the 4AFE appears the “next best” Toyota 1.6L
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This is interesting … as I understand you are saying that with the current engine we can “race” in a dignified way. You could give some details thinking that the block must be stock and the cams must have a maximum lifth of 9.9 mm?
Another interesting fact would be the timing advance data based on a type of cams.
right… 4age it’s banned… 
some other questions first
you say the block must be stock - but you’ve already tried after market pistons
do you mean it must be stock cc rating?
lastly. computer. you run a piggy back
would you consider an after market full replacement?
the big question is of the elephant in the room
how much money are you wanting to spend
a close one to this is how well do you want it to last
for example - you’ve already tried cheap computer and cheap pistons - but they blew up quickly
would you be happy to spend how much more to have it last how much longer?
or perhaps here’s another left field
i could build your engine here + tune it and send it to you to plug in if you don’t trust a local builder or tuner?>
and do you have the L700 chassis? cuore? big weight saving!!
if i understand correctly then you cant change block and can change intake
then i would go with 3sz head with ITB
maybe regrind port and polish head but so far seems they are ok
if budget doesnt allow then first step 3sz complete engine and look to modify later
super light flywheel
refresh gear ratios if you dont think theyre right yet
tuned with link computer
chassis change to cuore to save approx 100kg
Block issue is that for this series in Chille they have to use OEM from a car that was sold in the country.
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Ok … just as an update. Finally, the engine problem was the timing tensioner. For some reason it disarmed and did not deliver oil to the top of the engine. We changed the tensioner and everything went back to normal, however, I already have clearer the way forward.
I will keep the 1.3 engine and following @Patrick_Hart recommendation yesterday we went to buy this …
I hope it’s the right way…
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Ok … this is just a compilation of pics of the events that I participated in September and October, I know that I misbehaved with the post so I leave a little of these excellent photographs
I know it’s not good that the car takes off two wheels off the road, but you won’t deny me that the photos are super
Ups … I didn’t hit the piano
you can see the camber of this wheel in this pics
another track … Codegua
The little sirion has given me a lot of entertainment and a lot of learning in these two years racing with him, I hope to use that learning acquired in the L7 in the best possible way. 
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Fantastic!
The pictures of you throwing the car around the track is excellent.
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nice bro. they’re a good upgrade
you can use almost everything from the sirion into the mira
there are a few people on here already with information
send me a message if you need help with anything if you get stuck
or want a second opinion
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Hi there. Can’t really digest all the post but. Now in Malaysia, fastest KCAR to run at Sepang International Circuit is a Daihatsu TR powered by 3SZ-VE. 3SZ does has a lot of potential especially when you fit the K3VE2 cam into it. But it takes a lot of effort and R&D to squeeze power out of it. Using standalone ECU to manipulate VVT control is also a huge advantage.
Here is the onboard video.
I’m new to 3SZ as i used K3-VET before for running at sepang. But if you need info and help. Can look for it.
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Your link doesn’t work for me
Yes the mycil race car looks quick for sure
On their FB site
I haven’t had the pleasure of playing with a 3sz on the dyno yet
But I’m still very surprised to hear that you think the k3vet is not as good
3sz-vet however 