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Re: Waking up a Grand National

Posted: Tue May 12, 2015 10:55 am
by jwscab
my brother used it on plastic panels for the back of his malibu wagon and it appears to work very well. it's essentially paint with a lot more solvent than pigment so it bonds really well.

the trim paint is also awesome stuff.

Installing custom air intake

Posted: Fri Jul 08, 2016 11:00 am
by Coelacanth
This summer, I wanted to complete my project of building and installing my own custom air intake. There were 3 reasons for building my own, certainly there are already retail kits available...I'm upgrading the stock 3" MAF sensor with a 3.5" LS1 MAF sensor, and I'll be replacing the stock air-box with cylinder filter with a long 4" K & N cone filter. The aftermarket intake kits I've seen are almost all either 3" (which requires a half-inch reducer right after the bigger LS1 MAF sensor) or 4" (requires removal of MAF sensor entirely). I wanted to keep the pipe 3.5" from the LS1 MAF all the way up to the turbo inlet, which seems less restrictive to me. That was the first reason for fabricating my own. The second reason was cost; after all was said & done & bought, my intake probably cost about half of what a retail kit costs. Lastly, there's something to be said about doing it all yourself. It was a lot of work, test-fitting, measuring, cutting & filing, etc. but well worth it. 8)

Anyway, last fall I'd pretty much finished assembling the intake, but couldn't install it because you need a new MAF translator and computer chip to let the ECM work with the increased airflow from the larger MAF sensor...with the USD-to-CAD exchange rate not too favorable for Canadians these days, those parts ended up costing just shy of $400 CAD. I picked up some valve-cover breathers and an EGR block-off plate, might as well do some engine bay cleanup & dress-up while I'm at it.

Here's the assembled intake:
CustomIntake.JPG
Compared to the stock intake:
CustomIntake_Comparison.JPG
This mod usually requires relocating a charcoal canister, it's located right about where the cone filter would go. I decided to relocate mine beneath where the new intake tube will go. There's a V-bracket down there where the stock air-box bolts down onto; once removed, I figured I could stick the charcoal canister in that location. It took a bit of work to make it sit flush down there because the steel line/rubber hose going to the canister, and the plastic fender shield on the driver's side both obstruct it. I got out the tubing cutter and removed a section of the steel line and reattached the hose with a clamp. I then cut out a notch in the plastic shield with a Dremel and some filing. After that, the charcoal canister sat down real nice and polite-like, using one of the existing V-bracket mounting bolts to hold it down.

Area where the V-bracket bolted down:
AirFilterBox_MountingBracketHoles.JPG
After cutting the steel line, and showing approximately where I notched the fender shield:
CanisterLine_Cut.JPG
Charcoal canister relocated, nice and snug:
CharcoalCanister_Relocated.JPG

Custom air intake installed

Posted: Fri Jul 08, 2016 11:32 am
by Coelacanth
Before picture of the engine bay. Note the charcoal canister at the bottom right, with the red connector plug and 2 hoses running to it, and the stock intake/air-box assembly, a rather restrictive design with all the pipe bends and accordion-like intake tube up to the turbo.
EngineBay_Before.JPG
Picture after installing the custom intake and AXiS Interface (new MAF translator). The new translator and computer chip (ECM is located beneath the passenger side kick-panel) are calibrated for the stock injectors (for now) and allow the car to run properly on modern unleaded gas. Back in the 80's, gas had lead in it; modern gas doesn't work so well with old, early OBD computer-controlled cars. The new chip also removes the 124 km/h engine limiter. The AXiS interface allows spark advance and fuel adjustments at low & high load.
CustomIntake_AxisTranslator_Installed.JPG

Re: Waking up a Grand National

Posted: Fri Jul 08, 2016 11:39 am
by uniquenamehere
Awesome... love these cars!

Re: Waking up a Grand National

Posted: Sat Jul 09, 2016 9:20 pm
by Coelacanth
Got rid of the EGR today. Since the new chip isn't programmed for EGR, it just clutters up the engine bay.

Removing the EGR block: 2 nuts :o 1 connector and disconnect hose from T fitting on firewall:
EGR_Removal1.JPG
EGR solenoid & block removed:
EGR_Removal2.JPG
EGR_Removal3.JPG
EGR surface on manifold all cleaned up:
EGR_Removal4.JPG

Re: Waking up a Grand National

Posted: Sat Jul 09, 2016 9:23 pm
by Coelacanth
Some pics of the EGR block-off plate installed (a dab of black RTV compound will do ya) and the dress-up breather; simply ran a hose from the check valve on the left of where the solenoid was, to the T fitting on the firewall:
EGR_BlockOffPlate1.JPG
EGR_BlockOffPlate2.JPG

Re: Waking up a Grand National

Posted: Fri Jun 01, 2018 8:32 pm
by Coelacanth
Here's an update on my work on the GN this season...I haven't even driven it yet!

I got a pretty nice tax refund this year so I'm putting about a grand into the engine and several frame braces and body bushings to stiffen the ride.

I just got finished a pretty big upgrade, replacing the stock 28# injectors with 60# injectors and a matching TurboTweak chip. Had to flip a DIP switch in the AXiS interface to recognize the new chip. While I was at it, I put in new spark plugs and an MSD 8.5mm wire set.

I'm waiting for my big parts order to arrive, which will include a bigger and much less-restrictive one-piece 3" downpipe, 3 sets of frame braces and a body bushing set, a plenum power plate which is supposed to even the airflow into the intake--it's not to increase power, per se, but with the more even airflow distribution to all the cylinders, it reduces or eliminates detonation and lets you run higher boost. I also have a manual boost controller to install, so I can get the stock turbo to run 19 or 20 pounds of boost (stock is about 14-ish). That should make things a tad more interesting. 8)

EngineBay_AfterInjectorSwap1.JPG
EngineBay_AfterInjectorSwap2.JPG
EngineBay_AfterInjectorSwap3.JPG

Re: Waking up a Grand National

Posted: Fri Jun 01, 2018 9:20 pm
by romulus22
Always loved the sinister look of a Grand National. Also the capabilities they had in their day. Would love to have one but in today's prices I don't think that's happening. Look forward to seeing this car some more.

Re: Waking up a Grand National

Posted: Fri Jun 01, 2018 10:00 pm
by Lowgear
As someone who now owns a G-body car myself, I can appreciate what you're doing all the more. Keep it up! Too bad I'm about as slow working on mine as I am with my R/C projects. :? :lol:

Re: Waking up a Grand National

Posted: Sat Jun 02, 2018 1:30 pm
by Coelacanth
romulus22 wrote: Fri Jun 01, 2018 9:20 pm Always loved the sinister look of a Grand National. Also the capabilities they had in their day. Would love to have one but in today's prices I don't think that's happening. Look forward to seeing this car some more.
Buy yourself any Turbo Regal from '86 to '87...they had the same powertrain. In some cases, the Turbo Regals were even quicker, as they were hardtops instead of the heavier T-roofs. You can buy very nice examples for somewhere in the 20 grand range. With 2 or 3 grand in upgrades you'll probably be in the 12's; with a few more grand, you'll probably be in the 11's. You won't find too many cars with that kind of performance for that cheap. :)

Re: Waking up a Grand National

Posted: Sat Jun 02, 2018 4:41 pm
by jwscab
It's just a hop skip and jump to add an lsx based motor into a g-body. For the cost/performance/availability I wouldn't even try hunting down a turbo Buick.

Re: Waking up a Grand National

Posted: Fri Jun 08, 2018 11:31 pm
by romulus22
jwscab wrote: Sat Jun 02, 2018 4:41 pm It's just a hop skip and jump to add an lsx based motor into a g-body. For the cost/performance/availability I wouldn't even try hunting down a turbo Buick.
I couldn't do that to a real GN or T-type. A regular clapped out g-body that's a great idea though. For me a GN would be just a nice car to own and keep cleen and go on casual drives in the country with.

Re: Waking up a Grand National

Posted: Sat Jun 09, 2018 9:07 am
by jwscab
Yeah as long as the motor and car is complete enough. There aren't that many that are left that aren't restored or well cared
for. I was saying it's not worth hunting down the 3.8 to put in a car. Just use an ls motor in a g body.

Re: Waking up a Grand National

Posted: Sat Jun 09, 2018 12:28 pm
by GoMachV
We treat our metrics a little different around these parts.

Re: Waking up a Grand National

Posted: Mon Jun 11, 2018 11:45 am
by Coelacanth
romulus22 wrote: Fri Jun 08, 2018 11:31 pm
jwscab wrote: Sat Jun 02, 2018 4:41 pm It's just a hop skip and jump to add an lsx based motor into a g-body. For the cost/performance/availability I wouldn't even try hunting down a turbo Buick.
I couldn't do that to a real GN or T-type. A regular clapped out g-body that's a great idea though. For me a GN would be just a nice car to own and keep cleen and go on casual drives in the country with.
If you want a GN for casual drives...you want the wrong car. :twisted: