Turbo on a OEM engine

[UnhuZ]

Hi,

i may be facing an engine refresh, because my front HG is leaking.

As with everything i do, i like to be prepared to the possible scenarios:

1 - only HG leaking = new HG (ex. cometic), valve job and all rubbers and bits
2 - piston rings damaged = new pistons, etc

So i can plan my options, my question to all of you FI experts is:

What OEM components start to go as the whp increases? (my FI plan is to NOT to go over 500whp... ever)

From what i read here, the first thing to go are the OEM pistons and/or pistons rings.

Couple more questions:

1 - can i assume that if the only mod i do to the internals is to replace the OEM cast pistons to SOS ones,
keeping the OEM compression, then the engine will safely sustain more whp than with OEM pistons?

2 - What is the safe limit for the OEM Titanium rods?

My goal is to repair my HG problem, but if i need to mess with the block, then do it in a way that makes my
engine safer to sustain my goal of 400 up to 500whp.

Thanks,
Nuno

 

[doc_tai]

If ur car has 3.2 motor u have to install new sleeve before u can install forged pistons, 3.2 motor already has metal Hg from factory I would just stick with that, just use arp head stud. Look like u will need SOS stage 2 motor build

 

[UnhuZ]

Hi,

If ur car has 3.2 motor u have to install new sleeve before u can install forged pistons, 3.2 motor already has metal Hg from factory I would just stick with that, just use arp head stud. Look like u will need SOS stage 2 motor build

my car is an NA1, ence 3.0 and 5sp...

i will only mess with the short block if i have a problem with pistons and/or rings....

if i have to get new pistons/rings... i can still have the same bore or do i MUST have to
bore out to the next piston size ?!

Thanks,
Nuno

 

[doc_tai]

U have get next size bigger and bore out. Pistons, Hg, arp head stud is all u need for 500 whp

 

[UnhuZ]

Hi,

U have get next size bigger and bore out. Pistons, Hg, arp head stud is all u need for 500 whp

and can i buy new ones with OEM compression ratio (SOS sells them) and be safe up to 500whp?

Nuno

 

[RYU]

Install timeserts for your head stud bolts. Common issue for our local owners.

 

[UnhuZ]

Hi,

Install timeserts for your head stud bolts. Common issue for our local owners.

never heard of timeserts.... and it's common issue ?! can you ellaborate on that please?

EDIT: Just googled it.... don't i need this only if i have a thread problem ?! or should i use them together with
the ARP bolts to PREVENT a problem ?(due to FI pressure)

Nuno

 

[NA1MT]

Sorry to go off topic, but if your car is a 97' like your signature states, that would make it an NA2 with 3.2L and 6 speed. Unless of coarse, those specs are different in Portugal from USA.

 

[UnhuZ]

^ In US you use build year....in Europe we use first license year.... my car is from March 1997 and was built sometime late 1994 or early 1995.

 

[kookoo4nsx]

Depending what your budget is will depend on what rwhp you can achieve. A turbo kit alone is 8-15k. Then if you go over 400rwhp you will need a clutch in short order, plan on 2500-3k. As your goals rise closer to 500rwhp, your costs rise to double over a standart turbo kit as parts such as pistons and labor are quite expensive.(stage 2) 400rwhp on a stock 3.0 with metal head gaskets can be quite reliable. If your real goals are in ther 475-500rwhp range then plan on it from beginning and open your check book. The biggest factor in reliability starts with your install, but ends with a GREAT tuner.

400rwhp, fun and reliable great for budget constricted.
500rwhp super fast and can blow away 99% of street cars you are likely to encounter. 25k would be my guesstimate. Whatever route you go, have fun!

 

[UnhuZ]

^ my budget is tight...and this whole thing has to go in several steps....

i'm facing 2 scenarios:

1 - No need to touch the short block

This is only possible if i can be sure that the piston rings are still doing their thing (130Km miles on them though).
If so, i need:

- HG: Cometic or other metallic ones
- all rubbers, all gaskets and all little things to fresh block and both heads
- new crack pulley: OEM or ATI (steep price difference, and more noticeable on NA)
- new LMAs
- new valves: don't HAVE TO, but can use newer lighter ones to minimize valve train HP loss
- new valve springs: 130K on my OEM ones, may better replace them to refresh them also (lighter aftermarket ones)
- new head studs: ARP

Then, when the time (and money) comes, throw in a Turbo kit, but limit the output to 400whp MAX

2 - Have to touch the short block

This allows me to refresh and reinforce the bottom so it can sustain more power...up to 500whp MAX

if so, i need:

- all refered on "1"
- new pistons: SOS ones with OEM compression rate
- new rod and crank bearings
- upgrade oil pump to billet gears
- optional new main caps from SOS
- new rod bolts: ARP

Then, when the time (and money) comes, throw in a Turbo kit, but limit the output to 500whp MAX



On both points i HAVE to upgrade my Clutch and open up my transmission and check what's needed,
as it's grinding on some gears, probably because some of my clutch springs have gone south...

So.... this thread is more like if i need to follow #2 above, and what is the minimum i need to run the
engine safely at 500whp.

I know the Dyno tuning is extremely important and i really don't know anyone in Portugal i would trust
to do it....so when the time comes to go Turbo, that will be the hardest thing to solve.

The assembly will be all mine... slow and carefull... i'm pretty sure that i can do it myself

Thanks,
Nuno

 

[Nero Tenebre]

If you can afford it you should change your clutch at the same time the engine is out to save on the usual clutch labor.

 

[NA1MT]

With new main caps , I believe you need to have your block line honed. You are getting into mucho dinero.

Actually, just purchase an SOS Stage 1 assembly and be done with it. It would be perfect for your desired power goals.

 

[Nero Tenebre]

Yeah you might consider selling the car... But then you could just end up in the same boat again. These cars are aging and reaching wear limits. I bet there are many more out there in this situation that don't even know it. How did you discover it anyways?

 

[doc_tai]

If u can't find a tuner that can tune ur car, don't turbo it or u will be broke pretty soon. I know a lot tuner in us doesn't might to travel out of state.

 

[UnhuZ]

Hi,

If you can afford it you should change your clutch at the same time the engine is out to save on the usual clutch labor.

that's the idea... tranny and clutch at the same time as the engine, then Turbo Kit later.

With new main caps , I believe you need to have your block line honed. You are getting into mucho dinero.

what exactly is that or what does it involve?!

Actually, just purchase an SOS Stage 1 assembly and be done with it. It would be perfect for your desired power goals.

i can agree with you, but the shipping cost of an NSX engine back and forth over the atlantic kills it... this is why i want to do it locally.

Yeah you might consider selling the car... But then you could just end up in the same boat again. These cars are aging and reaching wear limits. I bet there are many more out there in this situation that don't even know it. How did you discover it anyways?

Selling the car ?!?! don't you think that is a bit overkill ?! :biggrin::biggrin:

i discover it after endless coolant leaks... i just wrote this post in NSXCB... go read it... it's so crazy that i think i only believe it because i lived it :wink:

If u can't find a tuner that can tune ur car, don't turbo it or u will be broke pretty soon. I know a lot tuner in us doesn't might to travel out of state.

I already talked with Cody that found a solution:
1 - I install everything and he give me a base map to get to the dyno
2 - At the dyno with my laptop and Internet, i send him the result of a pull and he replys with a new map, i upload and do another pull...etc...etc..

But this is something that i will think at the time...for now, i need to bring my engine back to top shape, using parts that will allow me
to run a Turbo Kit safer than 100% OEM engine.

Nuno

 

[E-Nough Logic]

Hi,


that's the idea... tranny and clutch at the same time as the engine, then Turbo Kit later.


what exactly is that or what does it involve?!


i can agree with you, but the shipping cost of an NSX engine back and forth over the atlantic kills it... this is why i want to do it locally.


Selling the car ?!?! don't you think that is a bit overkill ?! :biggrin::biggrin:

i discover it after endless coolant leaks... i just wrote this post in NSXCB... go read it... it's so crazy that i think i only believe it because i lived it :wink:



I already talked with Cody that found a solution:
1 - I install everything and he give me a base map to get to the dyno
2 - At the dyno with my laptop and Internet, i send him the result of a pull and he replys with a new map, i upload and do another pull...etc...etc..

But this is something that i will think at the time...for now, i need to bring my engine back to top shape, using parts that will allow me
to run a Turbo Kit safer than 100% OEM engine.

Nuno

Any time you use different clamping pressures or new mains all together the center line of the crankshaft can change. So in order to fix this the block needs to be align honed which a machinist bores out a new centerline for the crank. If you use the stock bolts this isn't necessary. I wouldn't run these unless you were running a stroker motor. My preference is to avoid this almost always. Changes to the centerline affect a few things most importantly is the oil pump clearances. The oil pump may need shimming/shaving depending on how far the centerline moved.

 

[EAC]

Took mine out for a drive last weekend. Stock motor @ 10 psi. I'm probably sitting around 500 whp.

Ran the shit out of it. Fun Fun!

 

[UnhuZ]

Hi,

Any time you use different clamping pressures or new mains all together the center line of the crankshaft can change. So in order to fix this the block needs to be align honed which a machinist bores out a new centerline for the crank. If you use the stock bolts this isn't necessary. I wouldn't run these unless you were running a stroker motor. My preference is to avoid this almost always. Changes to the centerline affect a few things most importantly is the oil pump clearances. The oil pump may need shimming/shaving depending on how far the centerline moved.

i think i understood what you say, but then a new question comes to mind: with machinist boring out a new centerline for the crank,
the holes will be bigger (as in wider) which makes the whole OEM color code for main caps obsolete and high precision measures need
to be made to determine which new bearings to us, right??

That is really something i don't want to go into... and if i read SOS description correctly, the problem with OEM mains cracking comes
with high whp numbers... 400 to 500whp is well below that, right?

Nuno

- - - Updated - - -

Hi,

Took mine out for a drive last weekend. Stock motor @ 10 psi. I'm probably sitting around 500 whp.
Ran the shit out of it. Fun Fun!

isn't that high on an OEM motor ?! You sure must had a wonderboy do the mapping ... that's higher than anything i read here with
OEM motor.

Nuno

 

[NA1MT]

I would just ask Chris @ SOS what the shipping would be, I know he has shipped motors overseas before.....might not be that bad. And to eliminate the tuning issue, I would seriously consider a CT or SOS supercharger setup and not worry about the tuning. You can always add a high boost kit down the road if you wanted to do so. That route would save you around $2500 initially as you wouldnt need to buy an AEM or pay for tuning.

 

[Mac Attack]

Nuno, I would skip the new main caps for the reasons hybrdthry posted. Also, I plan on chamfering the edges of my OEM main caps to reduce the stress risers on them and hopefully reduce their chance of cracking. Those edges are SHARP and can be chamfered without loosing any structural integrity. Also, lay the main caps on their side on a known precision flat surface to see if they wobble a bit and are warped. I think I recall this happening to another person on Prime. Mine were fine, but it's a quick easy check.

Also, skip the rod bolts for the same reason. I've NEVER heard of them being a problem, and for 500WHP you should be fine.

Sorry to hear about the HG, but have fun with the engine build!

 

[Blacknot]

Took mine out for a drive last weekend. Stock motor @ 10 psi. I'm probably sitting around 500 whp.

Ran the shit out of it. Fun Fun!

I agree with a proper tune 500whp is safe. I wouldn't go past that.

 

[mrbozo1]

I agree with a proper tune 500whp is safe. I wouldn't go past that.

Neither would I ..................... OOPS I already did LOL

 

[NetViper]

And to eliminate the tuning issue, I would seriously consider a CT or SOS supercharger setup and not worry about the tuning. .

SOS sc uses the aem and needs tuning.

- - - Updated - - -

Took mine out for a drive last weekend. Stock motor @ 10 psi. I'm probably sitting around 500 whp.

Ran the shit out of it. Fun Fun!

I don't know anything about a gt37r, but a precision 6262 did about 420rwhp at 8.5 psi on a stock 3.0 with comptech headers.

 

[NA1MT]

my bad....thought SOS system had two options....like CT.