87 GN Turbo Question - n00b To The Board

[AdReNaLiNe]

Hey Everyone,

Well, some background on my situation here and I'm hoping that i can get some answers, so pleaes read on and post some insight if you can.

Basically, my experience is in the import scene, Toyota MR2's, Supras, Nissan 240's and basically any Turbo charged car that came from Japan. (Most of you are probably boo-ing me now ) My uncle who actually inspired me to go turbo has an 87 Grand National and the bottom end of his motor is going.

I have built many import engines and I am wondering a few things before i begin to tear down his motor and begin to build it again.

1. Can I take a regular 3.8L V6 regal short block and make it a turbo?
(Obviously i would have to change the internals (crank, pistons and
rings))

2. If i were to go this route, I would like to bore out the cylinders and go with Forged internals, which do you gents think is the best bang for your buck setup using the stock Turbo? Or should i just get OEM rods and pistons as he would be using the stock turbo.

3. From anyones prior experience, can you think of anything i may want to keep my eye out for before undergoing this? Problem areas these cars usually have that i should keep an eye out for.

Guys, I really appreciate the help and any input you can provide. I figure the Power goals that I would like to achieve with this thing would be around 400-450HP

 

[scottyb]

I can't really answer your questions, but curiosity has me here. What makes you think the "bottom end is going bad"?

 

[AdReNaLiNe]

He's getting a 'Knock' in the bottom end, had his heads done not too long ago, but never concerned himself with the bottom end of the motor. Has close to around 260,000km on the motor right now.

I don't want to sound conceded saying this, so do not take me the wrong way please. But do you know how you can listen to an engine and just know where the problem is, or where the funny sound is comming from?

Just been around enough engines in my day to know I guess you could say.

 

[scottyb]

I don't have personal experience, but I have read many posts about guys who thought they had a knock and it turned out to be something else such as loose converter bolt, etc. I'm just suggesting make sure before you tear it down.

 

[GNocide]

you can machine the reg block a turbo one but it will lack the high nickel metal


you want to use a 109 number block-
or an all aluminum ta block-( money)

i don't think you need a block at all

i would do the billet main caps if your crank is good

my 02

 

[TurboTnZ06]

The block should be fine. Bearings might not be fine.

Check the front balancer- it can make a rattling/knocklike noise if thebolt isn't tight and it cracked behind the seal just ever so slightly. Ask me how I know

Tight tolerances (this ain't no chebby 350 tolerances) and good oil pressure down low is needed for the insane amount of low end torque the 3.8 makes.

Stock rods, stock crank, forged pistons. Wiseco's 35 over are in mine with stock rods and a 10 under stock crank and I put down 595 rwhp and 695 rwtq...

 

[AdReNaLiNe]

You guys are awesome. I appreciate all your input. The reason i want to just start with a fresh block is because I want to build the motor while he still has his in the car. So i will start with the 109 block and work from there.

Turbo TN, your putting down some good numbers with your bottom end, so i think i will probably follow your route.

I will check the front Balancer when i get a chance. and be sure that isn't where the noise is comming from.

Any other insight anyone can give would be appreciated?

TurboTN, are you running stock injectors/fuel pump and ECU/Chip Settings?

 

[TurboTnZ06]

Click one of my cars to see the detail page

Garage

Since that page was made, I upgraded to Moser 28 spline axles, 60# motron injectors with stock ECU and custom Jay Carter chips, catch can for oil bypassing the pcv.

In the mail this week hopefully is a 3 inch Impala SS MAF with a TranslatorII from Full Throttle Speed so I can control the tune better.

ARP studs are in everything, the bellhousing, wheels, intake manifold, headers....