Forged 4g93t - Questions/Concerns

[VIN18M]

After buying a complete forged 4g93t to drop into my Satria GTi I decided to strip the engine down and check everything with a fine toothcomb before reassembling and installing the engine.

Turns out everything was in good nick and all the goodies were there as promised, however the block did need to be decked and the bores were quite glazed.

I’ve now received the engine back from my machinist who decked and honed the block and checked all of the clearances were to spec.

Engine Specs are below:

Spool forged rods with arp bolts
CP forged pistons 20thou oversize
Nitrided crank
All rotating assembly balanced
Rebuilt head with valve regrind and new valve stem seals
Mild port and polish
Tomei 290deg cams 11.1mm lift
Tomei valve springs
Works adjustable cam gears
New timing belt kit and water pump including hydraulic tensioner
Metal head gasket
ACL Bearings throughout
Evo 3 Throttle Body

My Additions to the engine since purchasing:

Block decked and honed
Linished crank
ARP Head stud kit
ARP Main Stud Kit
Haltech E6X ECU
Evo 5 560cc Injectors
Genuine td05 small 16g
Punishment Racing stainless split dump pipe.
Permacool oil cooler kit
Aeromotive Fuel Pump

I just wanted to get some opinions before I start reassembling the engine next weekend.

1. I’ve read that most people say that the small 16g is probably the biggest size you’d go on a 1.8l before it becomes quite laggy, however with the cams being so big, is the 16g going to be more of a restriction on the engine? Would I be better off going for an 18g or 20g with these cams? I really don’t want this thing to be only used for straight line speed, it still needs to be good on the bends (besides the insane loss of traction). Will there be clearance issues with a 20g? Also, can I run my same aftermarket dump pipe on the 20g rear housing?

2. Also in regards to the cams - the head is yet to be run in since being rebuilt and I know that usually it would just be a case of cranking the engine over and winding the idle up to 2-2,500rpm and running them in for 20mins or so. However, the Haltech ECU that I have has a 4g63T tune on it from the previous owner, which had quite a few mods done. Am I better off using this to run the engine in till it gets dyno’d? I won’t be running an AFM so the factory GSR ECU won’t run the engine and I’m not sure it would support the idle of the cams and bigger injectors anyway.

3. Also in regards to running the engine in – I’m running chromolly rings which are quite hard and I really need to be able to run the engine in by driving the car as I’m concerned about glazing the bores again if I run the engine in at idle with an unknown tune. Any suggestions of ways to get around this?

4. Would the 560cc injectors be enough to support the 16g at 1bar of boost? If I went a 18g/20g would I need to upgrade these again?


Apologies for the long drawn out post, I just wanted to clear up these things in one hit and plan ahead rather than running into issues later on and posting multiple different posts at varying times.

Any help/advice/opinions would be awesome.

Cheers

 

[clone]

Good to see more 93t power upgrades

Quick question, are you going to be using the Aeromotive Fuel Pump inside your cradle?

if so let me know how you go with the fitting.

 

[VIN18M]

Yeah, I was planning to, I think the 340 model is a straight fit by the looks of it, and when comparing it to the stock VR4 pump I'm currently running it looks exactly the same.

However KNGGSR told me that the Aeromotive 700hp is a straight fit as he's running one, but I'm not sure if it will be overkill for my application.

 

[clone]

yeah i was more lookin at the Aeromotive stealth series pumps.

 

[4piknup]

Either run a afm for run in with the gsr ecu, or get the haltech tuned for run in as it is.

It would be nicer to run in with smaller cams even stock ones.

Injectors are big enough for the 16g with 1bar.
try the turbo as it is and save the expense of a bigger turbo for later if you need it.

 

[caged]

Cams are too big. Someone should be able to hook you up with a haltech tune from an Evo for run in. Dont let it idle at all on fresh rings, after a 15min drive it will be sweet to idle. You don't need to break in cams like you would on a solid lifter v8, just do the normal engine run in.

 

[caged]

And man up and run a big Turbo lol.

 

[VIN18M]

When you say cams are too big, do you mean that the cams are too big for the turbo? Or just too big in general? Can't they be dialled in earlier to help with response when I get the car on the dyno for the tune?

I would run a lot bigger turbo but it's FWD...!!!!

 

[caged]

Way to big for the turbo and in general. You can dial out the overlap but you can't dial out the duration and lift. I think I was running about 8.something mm lift and a mild 272 when I was at around 420whp on my 93. You will kill off a lot of down low power and don't have a big turbo to use it up top. When I played turbo fwd Hondas I found a bigger turbo a lot more street friendly due to the slower power delivery at slow speeds, I've never done any fwd Mitsi stuff tho.

 

[VIN18M]

Hmm so the 20G might be a goer then?

 

[khubner1]

do a 20g front on a 16g 7cm rear should net some good results. after i finish the asthetics on my coupe i'm going to start building a forged setups

thinking of including mivec aswell might have to look into an e9 or full standalone ecu

 

[VIN18M]

Not sure there would be much point in going a hybrid style turbo with the smaller rear housing as the rear housing will still create a restriction.
Any idea when I could expect to see boost on this setup with a 20g? I suppose this would mean binning my Punishment Racing dump pipe?

 

[CYBORG-X]

the cam duration will be too long, you loose captive effort on valve overlap.
how many angle valve job is it?? also do you know your comp ratio??
id run a td05-16g7 with a ported and re-shaped manifold that should work very well, unless is a low comp engine, then you will need a larger front housing
in reguards to the oil cooler, ensure it has an oil thermostat oter wise you may get oil fatigue
running the motor in, try do it on the dyno, or drive it, motor will be run in, in less than 40 min.

 

[khubner1]

on a 1.8l your not going to see a restriction from using the 7cm exhaust housing unless you making giant power levels in excess of 250kw and if you do you can always upgrade to an 8cm one.

 

[GeoKez]

^^
I just put a td05 big 16g on my 4g93. I see 20psi @ 4000 and that is with a very mild cam. All the advice I have had is to drop the ex housing to get it 'best' combo. If op's is a street car, I doubt he would get it 'on song' as often as he would like with anything bigger.

My $0.02

 

[VIN18M]

The engine is still running standard gsr comp, probably ever so slightly higher now that the block has had 15 thou taken off due to it being decked but thats not enough to make much of a difference to the comp.
I'm not sure on the exact specs of the valves as the head came assembled and I haven't dismantled any of it.
Would the larger 16g be much different to running the td05 16g exhaust housing with 20g comp cover and wheel? Would be a lot easier to grab a kando 20g cover and cartridge and fit to my existing exhaust housing surely? Spool up would be quicker with more top end?

 

[khubner1]

i'm on a 16g big (7cm exhaust housing spool is quite progressive and doesn't run out of puff up top like the td04 did. only running the std 10pound boost.

if anything for myself i'd like to get a 6cm housing to use to bring the boost on alil quicker but finding one is proving troublesome they all sem to find the bin rather than the for sale pile. the 20g wheel and comp housing with a std evo 3 16g 7cm rear should flow more with characteristics similar to that of a 16g alot of people do this since the only other way to run a 20g is to go a td06 which is much larger

 

[VIN18M]

Ok I'm seriously considering either a Kando td05 20g or a td06 20g (internally gated).
I'm hoping the td05 20g will be sufficient as I wouldn't need to change intercooler piping with the outlet facing the correct way, not sure about the td06z
Anyone have any idea when I'd be likely to see full boost on my setup? (1bar) I know it's just a stab in the dark but any input would be great before I lay down the cash on one of these turbos.
All reviews I've read have been really good on the Kando Dynamic turbos, I was looking at GT pumps but they are a lot more expensive and might not provide the spool up I'm after anyway.

 

[EVOCPE]

Get a kinugawa TD06SL2 20G they look identicle to the oem td05 16g but with the comp and turbine housings machined to suit the bigget wheels
Im using 1 on my 63 with stock piping

 

[VIN18M]

What's the difference in exhaust housing sizes between the Td06 20g and the td05 16g?
I'm leaning more towards the td05 20g only due to the spool time on the 1.8l and with the same exhaust housing size as the 16g it might eliminate this a bit but still have enough puff for top end.
My head is spinning trying to work out a good street combo without having to swap these cams out.