new owner and need some guidance on build

F

fearsno1

New Member
Joined
Nov 24, 2015
I am a new member and I own a performance shop,but mainly deal with late model mustangs, but I have a long time customer of mine that just recently bought a 87 GN, car is in fairly good shape, the trans is being rebuilt as I type this as it was slipping 1-2, motor is all stock with what he was told had 100K miles, compression on it is 145-150 psi across all cylinders, it is a bit cold natured and will stall a few times before warming up, i am pretty sure it has a ton of vacuum leaks, as all the hoses are in drastic need of replacement, but my main question to you guys is really what to do and not to do, I have never dealt with one of these before but have always liked them. Owner does want to replace the turbo and do a front bumper exit exhaust, doesn't really want to build the motor yet. He says he wants a low 11 to high 10 second car. Maybe his expectations are way off but like I said, I am just learning and don't know yet, so any advice on the direction to go would be awesome.
what are the stock motors good for in HP?
 
Front bumper exit exhaust?

Tell him to sell the car & to deface something more generic.
 
What did be drive before this?

Keep it simple.

List what mods the car has and people here can guide you from there.

D
 
~JM~ said:
Front bumper exit exhaust?

Tell him to sell the car & to deface something more generic.
Click to expand...
seriously man? the car will still be true to it's roots, its not like i am doing a LSX swap! chill out! He just wants a street beast and nothing says that like a 4" front fender exit exhaust.
 
EVIL said:
What did be drive before this?

Keep it simple.

List what mods the car has and people here can guide you from there.

D
Click to expand...
he currently drives a 2011 Ford F-150 Harley Davidson with a lengthy mod list, but it makes 590RWHP and 700+ on nitrous.
the car is bone stock right now and simple is not his forte', he has always wanted to own a badass GN and that is what i am tasked at doing for him. i am just looking for some guidance to point me in the right direction and get started. Thanks
 
fearsno1 said:
seriously man? the car will still be true to it's roots, its not like i am doing a LSX swap! chill out! He just wants a street beast and nothing says that like a 4" front fender exit exhaust.
Click to expand...

You originally wrote: "front BUMPER exit exhaust".

Bad ass GN & stock 100+K mile engine doesn't usually go together well. Minimum requirement would be to change out the timing chain & probably the valve springs. Start searching & reading. These cars were meant to be stealthy & quick with a full length, quiet exhaust system.
 
You can go 12s pretty easy, 11s if you tune well and play it safe. Anything more and you have to throw alot of good parts, money and time at it. It is a heavy car with a small engine. That engine has to be given alot of turbo boost and octane/fuel to make the power output needed. And that power transmits to everything in the drivetrain. You will find the weaknesses the quicker you go. If it knocks, you can lose a headgasket best case. The trans is next. Then suspension to put the power to the ground, plenty of pitfalls there. The good news is there are plenty of people going quick and safe though it is not simple.
 
Where are you located. My best advice to any new owner,preformance shop or not would be to find someone near you that works on grand nationals and seriously talk with them. From what i have learned high tens are available on mostly stock gn,s but ive only read about it being done by long time turbo car guys with perfect tunes. From what im told i have a ten second car,i dont really know havnt been to the track yet. What i do know is it a long long way from stock,and alot of trips to the bank. Also took a couple years to complete as it was done in steps not all at once.
 
~JM~ said:
You originally wrote: "front BUMPER exit exhaust".

Bad ass GN & stock 100+K mile engine doesn't usually go together well. Minimum requirement would be to change out the timing chain & probably the valve springs. Start searching & reading. These cars were meant to be stealthy & quick with a full length, quiet exhaust system.
Click to expand...

i realized i put "front bumper", but in the market that i am used to (late model mustangs) the front bumper extends around to the front fender and that is where i normally run the exhaust out of. Sorry for the confusion. i will put the timing chain and valve springs on the list. i realize that "most" of them are quiet with full length exhaust but one thing i have learned is that a car is determined by a status qou, but yet what each individual owner wants, so just becuase the "typical" GN is built from a "cookie cutter" type build sheet, that doesn't mean they all have to be that way. I build cars that are "custom" and represent what the owner wants and sometimes that is cars that have been done over and over again and sometimes they are one off builds that have never been done before or isn't typical. Thanks for the advice and yes i will read up and see what i find, last three days has filled my life with GN EVERYTHING! LOL
 
I think a fender exhaust would be bad ass. Maybe a little loud and menacing but cool it's just a fender. Let me explain, I am no professional: With that being said, 10's is obtainable but how you get there is what matters. Beating a 100k mile engine? I would pull it, inspect bearings and replace every seal on it...especially the rear main.

Might as well do some work on the stock heads while you're changing those 30 year old steel head gaskets too, and pop in a roller cam because that stock can is probably half worn. Injectors, computer chip, bigger turbo and intercooler is on the list..and ALKY! Stock motor going tens is high boost, you'll need the ALKY unless you're running race gas. Post some pics!!
 
Add in a new fuel system, headers repaired, ic cleaned & Dutt necked, [at the minimum]. The radiator is most likely junk. Ft and rear suspension, body mounts, all need to be replaced.
The car will need gauges, data recording equipment.
While you are having the trans built, have someone that knows wtf they are doing. A 10 sec 200 is not an AAMCO trans job.:smuggrin:

As Gene asked, where's your shop located?
 
It's going to nickel n dime you if its stock. Everyone here is cheap, but really plan on a bigger budget, at least $20-30k to get it right just in drivetrain updates if I was doing the work on my own car. Bowl port the iron heads at a minimum and put in a billet hyd roller cam 210-210 ish will suffice. Get a used TE45a turbo, a used 3200+ lockup stall converter, Turbo tweak chip, fuel pump, hot wire fuel pump, adjustable fuel pressure regulator, 60# injectors, MAF translator, 4 inch slot style maf and intake, alky injection. Heads, cam, turbo and converter is probably the best bang for the buck to do all at the same time to get them to work together on the street and strip, whatever the goal is.
 
He may have meant fender well dump as well.
I would like to see a photo when completed.
 
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The only thing I would add to the other suggestions listed above is a bigger CAC and piping. Gotta cool that air and get the volume up to the throttle body without a flow loss at high boost and rpm's. A visual monitor of the parameters is a MUST if you want peak performance without the chernobel effect. I've been a mechanic for only 43 years, mostly heavy trucks, and am still new to the turbo Buick system. I have seen many people waste many $$$$ on "performance parts" and upgrades that either don't work, not compatable , or are installed by a butcher, then come to me crying the blues about "all the money they spent and it still don't run right". The best advice I can give is when you start this project make sure they have the budget to buy only quality parts, build everything to hold up to the power and performance of your end goal, and only do this as a package deal, ie trans/converter, eng rebuild with quality forged pistons, cam, balance, upgrade cac, turbo, throttle body, injectors, reg, fuel pump, fuel lines, exhaust, cooling system, check and rebuild the suspension (don't want wobble at 120 mph) good tires, and make sure the brakes get premium pads and the flex hoses are new, use dot 4 fluid. There are many perf parts and upgrades available and the guys on this site will let you know which ones will get you to your goal. Good luck on the build.
 
As above, the 2004rbuild isn't for just any local th350/400 guy/shop. If your guy doesn't have a track record of successful 2004r builds you might be better to go get it. The servo, vb and governor at specific to the turbo regal. If you have it at a shop that thinks "they are all the same" run don't walk away from them.

Plenty of cars deep in the 11s through full exhaust but hey a fender dump might be just what your customer needs .

Tires to hook it, plenty of boost(high octane fuel or alcohol injection) and a well tuned combo your customer will be clicking off some high 10s regularly.

Oh, and welcome to the site.
 
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Where are you located ?? Some big time help could be right around the corner , and maybe an E85 build !!
 
i am located in Lafayette La. and E85 is def on my list of mods too. as i run E85 in my 1100+ HP GT500
 
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