Piston Rod advice for -90 Talon AWD Tsi

[le0net]

Hi all!

I been searching and found some info, but not what i actually wanted to know. Sorry for this long post, i will try to end it with the specific things i want to know but i think i need to put in some background first.

BTW i live in Sweden and dont feel there is enough experience on the forums here so im turning to you guys.

I just bought a Talon AWD Tsi -90 with a engine problem, the engine runs and dont have any strange sounds but i cant get it to rev properly, it sounds like its only using 3 cylinders and from the 1 cylinder it leaks oil through the exchaust manifold that is leaking, i took out the spark and its all oily, so i suppose something bad happened to that piston, or rings. I got the car cheap so i bought it with a rebuild in mind.

I will open the engine ASAP to see what happened.

My goal is about 350-400hp since i read that the tranny wont hold for more than that on the 1990 model.

I have the following parts:
I have a Walbro 255 that i will rewire.
I have Denso 660 injectors
I just payed for a FMIC and GM MAF and a Maf translator, the GM Maf will be in blow through mode. All needed stuff to get this connected was included in the deal.
I have a brand new SAFC II
I have payed and am waiting for a bullseye power T04b 50 trim 38mm wastegate, a evo III manifold and a ported o2 housing that i bought from a guy that had his add both here and on ebay, hope just to get them He has been posting quite much on this forum so i hope i can trust him.

And i will need the following things:
Boost gauge.
Aeromotive FPR and the fittings, will the stock fuel rail be enough?
3" exhaust all the way.
ARP studs

Now to the question
Will the stock rods hold for my planned setup or do i need forged ones?
What pistons should i choose, found out that many uses 2G pistons and that those give a higher compression ratio, and that those are .020 bigger than stock 1G, or should i go with forged ones. Is there any benefits to increase compression? And last but not least, tips on a head gasket.

Sorry for the long post. Hope you can help me.

Leif

 

[Mitsubishified]

Well the pistons and rods are fine for 350-400 hp. Going forged is for people who want crazy numbers like around 500 hp. Machining the rods are required if using 2g pistons and 1g big rods. The stock fuel rail is fine for the fuel that you want to put through it. Im in the same boat as you are, i just want my talon to be around 350 hp and ive decided to go stock all the way, with 2g pistons on 1g big rods of course. The stock head gasket is fine up to 400. If you like you could use various other ones, www.ffwd.com they have a few on there website however i don't know how the new titan gasket holds, supposedly its supposed to be really good from what darren says at ffwd. Aslo Ive heard many complaints about copper and never to use them on our cars so i wouldn't go with a copper head gasket period. http://www.jacksonautomachine.com/ has a head gasket that i have used that is rated to 450 hp and you have to deck your head like all other head gaskets however you don't need to deck your block. I hoped to answer some of your questions.

 

[le0net]

Thx for the quick reply.

So i could go with stock 1G rods, pistons and gasket and be safe up to 400?

I havent opened the engine, but if i understood it right i should have the big rods as stock, so basically i just need one new piston to replace the broken one, assuming just the rings are broken and there is no damage in the cylinder.

Just wondering if the rest of my stuff is "overkill" for the hp im wanting to have, i suppose the 14b,stock ic and injectors cant handle much more than 300hp so i needed new parts anyway.

The turbo seller said that it would be good for up to 450hp, the FMIC seller said the same, but is it bad to have a little oversized parts?

This car will be a daily driver so i hope my setup would work good for that.

Leif

 

[talonismyfriend]

i got a 91 talon tsi with a big 16G turbo and i put new pistons and rings "stock" aka 85mm
boost controll and guage .new timing belt , spark plugs,air filter and did a few cheap aka free mods. new clutch and i smoked my friends 2006 M3 THREW FIRST AND SECOND
so yeah... itcould be he suck at driving or im da man but real if u want know the way to go look at this its realy the best way to go http://www.dsmtuners.com/tuning-guide/1gturbo/ do the free mods first and then got threw the first stage and then second stage its pretty much the best PS i was a mits tech.. most important is making ## car sstrong befor throwing power at it

 

[le0net]

Yeah, i have read it several times So i will just check the condition of the parts, run stock internal to begin, with the external mods i have, and if i want to take out more hp i just have to replace rods and pistons to forged ones.

Cant wait to get this up and running.

Thanks...

Leif

 

[le0net]

--------------------------------------------------------------------------------

Ok, made a comp test and got following:
Cyl 1 - 0 did not happend anything on the meter...
Cyl 2 - 145
Cyl 3 - 145
Cyl 4 - 145

Well, suppose its the rings or worse...

Leif

 

[le0net]

Ok, i opened the head, and it did not look nice... I dont know how much the block can be bored, but the
"scratch" felt quite deep, i suppose i need to take it to someone who does boring to get a estimate of what oversize i will need...

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Lets see what comes next

leif

 

[OnMyWayTo12Secs]

The stock bottom end will last for as long as you treat it nicely. The people that say its great up to 400 HP are lucky. If you have the money and want to do it right, build the motor for boost, IE CP or Wiesco pistons and Eagle rods, and then have the peace of mind to know your rock solid!

 

[brute]

Looks like some sweet scarring

You may need a new block, but wait until others jump in...

If the block can be salvaged, I'd say go with the rods you have, but get some pistons from a 2g. It will raise your compression from 7.8:1 to 8.5:1. This combo will be fine for the numbers you are looking for.

Forged internals are not necessary unless you plan to run N02 and/or 30+ psi

edit: about the most any block can be bored is like .60... those scars look really deep, and you may not be able to bore it out of the cylinder wall

 

[DSMrallyDriver]

60(.060) over stock is the maximum you can bore the block. If they machine shop can't get the walls smooth at that bore then you need to pick up a new block.

 

[le0net]

The scars ARE really nasty, and deep. I was wondering that it might be better/cheaper to go with a new stock block. Does any 4G63 block work, are they the same for the different models, is it just the stroke and top that differens them? Are the block different between 6 and 7 bolt?

Leif

 

[Quasimondo]

Have the machinist take a look at it first. .060" is the max you can bore these pistons out, but he'll tell you for sure how much the cylinder would need to be bored out. It might be less.

If the block is unsalvageable, get another six-bolt block. The crank and rods between the six bolt and seven-bolt engines are not interchangeable, and the six-bolt rods are the stronger ones between the two.

 

[le0net]

One more Q.. Will any 6 bolt block do, i mean i can find a few smasched N/T eclipses 1991 but no Turbo models, i suppose the rods and pistons on a N/T is different since they have different compression, but is the block the same?

L

 

[le0net]

Hi *

Got the news from my machinist, he had to bore .060 (86.5mm) and im looking for options. There doesnt seem to be any std DSM pistons with that bore, only one i found was Wiseco. Would it be best to change the rods also or will the std rods be "good enough". As i wrote before im planning to stay around 400hp but might want to put in some NOS later. Also will change all the studs to ARP ones.

Leif

 

[GVR4592]

If you use ARP main studs you have to get the mains line honed. I know Ross and Wiseco both have .060 over pistons, that looks like your best bet at this point. I don't think you can get stock pistons that large. The stock rods will work fine, if you want some extra insurance get ARP rod bolts.

 

[Quasimondo]

One more Q.. Will any 6 bolt block do, i mean i can find a few smasched N/T eclipses 1991 but no Turbo models, i suppose the rods and pistons on a N/T is different since they have different compression, but is the block the same?

L

The block is nearly the same, the only difference is that the n/t blocks don't have oil squirters to help cool the pistons. It's something that's nice to have, but there's more than enough folks here who have used n/t blocks for their buildup and have suffered no ill effects from the lack of oil squirters. The rods are the same, the pistons are not.

 

[mra4886]

If you are upgrading the pistons you might as well upgrade the rods. mixing forged and oem isnt the smartest thing to do.

 

[le0net]

Ok, Wiseco pistons and Eagle Rods ordered.. I also ordered Main and Head ARPs, the Rods included ARPs. What about main and rod bearings, im pretty sure this engine never was rebuilt, and the mains looked really nice, so i suppose a std. bearing kit would do.. Anything to think about there?

Leif