well that alpha car actually had a St185 TTE Celica block in it. Thats why it has the HKS custom drag pistons. The TTE block goes for £5000 for the bare casing but is alot stronger, The pistons have to be custom because the deck hight on the tte engine is 3mm lower than the normal 3sgte so off the shielf 3sgte pistons won't fit.

also be very careful with sleeves, yes they are much stronger but when you start running higher bhp levels we've found the block actually falls apart around the sleeves because of the torsional stress placed on the block from launching the car and the weakness of the casing because of the amount of material removed to fit the sleeve to start with. On the drag research car the sleeved blocks have always failed before a normal run of the mill gen 3 3sgte. Also with dalton sleeves the expansion rate on the top lip is a little funny, another thing we've found is that at high bhp levels on the dyno so minimizing torsional stress the topring expands faster than anything else causing it to expand pushing the head and gasket upwards, If it didn't lift the head it causes a weakness in the headgasket that lead to eventual failure. This is why i now stay away from sleeves from the results of our extensive testing.

don't count out gen 3 engines because of all the bullshit rumours. I've ultrasonically scanned hundreds of 3sgtes from rev 1 to 5 and there all similar, just normal casting variations nothing that i would say sets a trend to one being stronger than another, and the later thickwalled blocks are also again rubbish.

The later model caldina blocks are a good contender as there basically the same as the mr2 3sgte but the waterpump head stud is a solid chunk of cast over being a small protrusion which helps to the cracking issue in that area which is where all the ones i've seen have failed. Head lifts in that area putting stress on the block casting around the stud threads.

Hope that helps

Tim
TB Developments

Well I finally got stuck in and stripped down the engine today. I have it on an engine stand and it was straight forward. I would recommend an engine stand for this type of work, as I was able to get to every nut and bolt easily without having to be a contortionist.

The block, JUN stroker kit and a few other items will soon be on the way to TBDevelopments. The reason I want Tim to work on the block is because he uses a torque plate when the block is being bored & honed.

no worries mate anything i can do to help

Tim
TB Developments

Cool, good to know there will soon be another wicked 2 tearing up the roads

Oh sweet, job luck with the build you lot.

I just weighed the stripped block at 37.4 kg.

oh yeah its a heavy un lol

Tim
TB Developments

Marty J wrote:
I just weighed the stripped block at 37.4 kg.

SHIPLY is your friend... www.shiply.com

I had a good discussion with Tim from TBDevelopments into the wee small hours last night. I don't know how he does it and then gets up to work. Tim made some helpful suggestions and is going to install the full rotating assembly. I have not met Tim yet but he seems like he wants to do the best he can with what ever the customer has got. That's why I am sending him my engine. There are a couple of parts going on that are not common (to my knowledge) on a 3SGTE rebuild/upgrade. A girdle to strengthen the bottom end. This is basically attached to the main caps using ARP studs with spacers. The other part is a crank scraper with a Teflon blade which will help keep oil off the crank and in the sump. Here is a link that can better explain what it does : www.crank-scrapers.com/What%20is%20a%20crank-scraper.html

just got back for lunch, lets say i was a little late thismorning lol

Its ok i didn't have much to do, i'm waiting on this water hose for a 500bhp build thats stopping me going any futher with it at the moment, and that hasn't arrived yet

Tim
TB Developments

A quick update. Tim has received the engine block and necessary parts. So now I will wait for Tim to work his magic and transform Toyota's 2.0 to a 2.2 JUN forged bottom end

Tim if it's not too inconvenient, maybe you could take some photos as you progress

Cool!

Karma click for both for good luck

Hi Marty, I saw your post on MR2oc.com about machining sizes. If you send a polite PM to Ishii on that board, he could get you the details. He is in Yokohama and is an MR2 guru.

OK thanks Geoff

I was on the phone talking to a guy at Cosworth UK. He said that the 87mm refers to the bore and not the piston size. So for the 3SGTE JUN stroker kit the the bore should be 87mm - 87.02mm.

I've just spent 30 mins hunting around the JUN website... damn they've got some awesome looking stuff!

hey buddy.

i really need a proper number. I've measured the pistons this morning and there all very slightly different sizes, this is normal in forged pistons. This is why you measure, add clearance then bore each cylinder to each piston.

So #1 piston will go into and only #1 bore.

There some are under 87mm, and a couple of over.

Now if you take his word that the pistons are under size of 87mm (there not) and just bore to 0.02mm clearance thats a clearance of 0.0007". CP pistons which are made of the same material and similar design are 0.0035" so the JUN ones are 5 time smaller than CP (this isn't correct) and still 2 times smaller than standard toyota.

this will seeze up the first time it comes onto load.

The other thing he said in the email was the rings are perfect gap and won't need filing yet you look at the japanese paperwork and right in the middle is a spec sheet for piston ring gaps and what they should be machined to.



Tim
TB Developments

right spoke to cosworth, the first guy didn't have a clue what i was talking about, he was just saying

"oh we don't even measure the actual piston we just bore what it says on the side of the box" thats really amature i'm afraid and he'd even even heard of a torque block for the head.

So got transfered to some guy from product development who as soon as i said he said on bare with me i've got another call, then never came back.

I'll try again tonight after i've done a little job and run upto toyota.

Tim
TB Developments

Ok thanks Tim. I am very suprised at the way Cosworth are dealing with this. How did they ever get into F1 if this is the way they run things ?

well i spoke to the guy first who didn't understand what i was on about, and i said there was a slight difference in the pistons, how do you account for the difference in clearance if the bore size is fixed. He just said well thats within our tollerances.

PMSL the difference i was talking about is 4 time larger than the torque block distorts the block.

maybe it me being to anal over things

Tim
TB Developments

Anal is good LOL if you are going to build the engine this carefully then this will show others how well you do it

Marty I will PM you Ishii's email address, from what Tim says maybe the best answer will come from JUN themselves. Might take a while to get it but worth doing right once etc..

ok well let me know asap. i've only for under 4 weeks to build this thing before the deadline on collection and the machinist is going to have it for about 3 weeks

Tim
TB Developments

I finally received a reply from a JUN mechanic .

From: Junichi Tanaka [mailto:tanaka@junauto.co.jp]
Sent: 11 April 2010 02:19
To: Martin O'Donnell
Subject: Re: Piston and piston ring clearance

JUN Auto Mechanic
3-1-7 Sekimachikita Nerimaku Tokyo
Tel 81-3-3920-4165 Fax 81-3-3594-2689
April 11
Dear Mr. Martin
Thank you for your mail. I was out of office for a while.
1. Piston clearance 0.05mm-0.07mm
2. Ring gap
1st 0.20mm-0.50mm
2nd 0.25mm-0.50mm
Oil 0.20mm-0.60mm
Thank you,

wow cool!

that is tight on the clearances, i'll put them at 0.06mm which is 0.023". still tight compared to the 0.0035" of CP and the like but if you say thats good i'll go with that

Tim
TB Developments

Tim I would have gone with your spec if I had not received the info from JUN. But now I have it I would like to go with what they recommend and what you said in your last post. I am glad that you are not a mechanic that just wants to rush the job

Geoff thanks for the pm, unfortunately Ishii didn't get back to me

no worries mate of course i'll go with there sizes, i only said about the CP ones because they use similar material spec and using one similar would have been better than just picking a number out the air

I'll drop the bits down to the machine shop tomorrow

Tim
TB Developments

Tim I meant to ask you what is the black 'paint' on the JUN crank ?

its just an anti corrosion coating to stop it rusting nothing special

Actually the crank isn't anything special either its a $80.00 5efe standard toyota crank thats offset ground. The normal 5sfe crank the conrod journal diameter is larger than the 3s so you machine them down to fit the 3s conrods. But because its a few mm smaller you can offset grind it.

Standard there 91mm stroke, they've offset ground this to 92mm, very similar to the kits i sell which are 93mm offset ground.

Then you can use stock or uprated 3sgte conrods to work with that crank.

difference between this kit and my own is that the stroker is 1mm shorter but you use 87mm pistons where i use 86.5mm to obtain around 2.2ltr with both kits.

hope that helps with explaining some of the details of the kit as well.

Tim
TB Developments