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Vigo
Vigo UberDork
11/25/13 11:45 a.m.
it helps if you seat the torque converter properly

Those few words can condense long hours of suffering into one short sentence. I finally conquered that issue with sheer experience by working at a trans shop for 2 years, but that's not a viable solution for everyone.

MadScientistMatt
MadScientistMatt UltraDork
12/29/13 4:00 p.m.

No pictures with this update - though I can get some posted soon. It's close to ready to crank up and see if it starts. I mostly need to finish a bit of wiring and make a new brake line for the rear brakes - the original ran too close to the passenger side exhaust. I tried to gently re-bend it, and instead, the line cracked. Was hoping to avoid opening things up and bleeding the brakes - I can be lazy like that...

MadScientistMatt
MadScientistMatt UltraDork
1/19/14 3:57 p.m.

Last Friday, I tried to get it started - nothing. Some probing revealed the starer (a junkard part) was getting 12V. I didn't have much to lose, so I tried taking the starter apart and greasing it, and got it turning. Wouldn't start, but Ben at the shop suggested I try some starting fluid. It fired right up and stayed running for about a minute. There's still some things I need to fix - there's a coolant leak, one brake line broken when I tried to bend it out of the way of the exhaust, and a lot of tuning. But it looks like it's pretty close to being back on the road.

MadScientistMatt
MadScientistMatt UltraDork
1/22/14 3:35 p.m.

Coolant leak should be fixed: Instead of trying to solder a fitting into the radiator heater hose connection for the steam line, I capped the fitting and drilled and tapped the top of the water pump to add a 1/8" NPT aluminum hose barb for the steam line.

Ordered a bracket kit today from Street & Performance to attach the TH350 kickdown cable to the throttle body.

MadScientistMatt
MadScientistMatt UltraDork
2/8/14 2:09 p.m.

The bracket was ridiculously overpriced - $50 including shipping gets you a flat 2" piece of sheet metal with two holes in it, one of which makes no sense whatsoever. Would have fabbed my own if I'd known what I was getting. The kickdown cable wasn't long enough to reach; I'm trying to adapt something that I think was meant for a 700R4.

Other stuff that I need to get some pictures of:

  1. The exhaust was pretty easy to set up - Camaro manifolds exit straight down and more or less lined up with the stock pipes, so I just needed a set of 2 bolt flanges, 90 degree bends, and a couple feet of piping. Someday I'd like to come back and put a crossover pipe in there.

  2. Ended up attaching the MS3-Pro ECU to the A/C evaporator box with riv-nuts. Sounds a bit crazy but it ought to work. It's pretty lightweight and designed to go under the hood, but there wasn't any other good spot on the firewall.

  3. Radiator hoses from a 2005 Silverado are almost a direct fit. I did have to trim an inch off both ends of the lower one.

  4. Bent a new brake line to snake around the exhaust better. After getting nowhere with a Mity-Vac, kcbhiw suggested I just open the bleeders at the back one at a time and gravity bleed the system. Got all the air out with a lot less work.

The truck starts and runs, and I've moved it a couple feet under its own power yesterday. Another project was blocking it in, but on Monday I'll run it around the parking lot and see if there's anything else I need to correct before it goes on the dyno.

AngryCorvair
AngryCorvair PowerDork
2/10/14 2:41 p.m.

In reply to MadScientistMatt:

cool!

MadScientistMatt
MadScientistMatt UltraDork
2/10/14 3:54 p.m.

Got it out of the shop... leaving a trail of Dextron. Retightened the compression fittings I'd used to splice the trans cooler lines together, and that seems to have fixed it. I drove it up and down the road a little to make sure things were working OK.

So far so good. Looks like all I have left to do is get it tuned, connect the kickdown cable, and some tidying up. Even without tuning, it seems to run a bit better than the carbed 350... although the carbed 350 might have been "without tuning", too.

crankwalk
crankwalk HalfDork
2/10/14 4:42 p.m.

That looks amazing.

calteg
calteg Reader
2/10/14 4:46 p.m.

Getting a project on the road is always an amazing feeling!

DILYSI Dave
DILYSI Dave MegaDork
2/11/14 10:11 a.m.

Metallic light blue, white top, 3" drop on 15x8 Corvette Rally's and white letter tires.

4cylndrfury
4cylndrfury MegaDork
2/11/14 10:36 a.m.

Video or ban

MadScientistMatt
MadScientistMatt UltraDork
2/12/14 9:04 a.m.
DILYSI Dave wrote: Metallic light blue, white top, 3" drop on 15x8 Corvette Rally's and white letter tires.

That would look great, but getting the body straight enough would be a PITA - might be better to start with different sheet metal on the current chassis if this one falls apart.

The suspension could use some work, though; it sits a bit cockeyed up front. I wonder if I could find some used drop spindles somewhere?

tuna55
tuna55 PowerDork
2/12/14 9:12 a.m.
MadScientistMatt wrote:
DILYSI Dave wrote: Metallic light blue, white top, 3" drop on 15x8 Corvette Rally's and white letter tires.
That would look great, but getting the body straight enough would be a PITA - might be better to start with different sheet metal on the current chassis if this one falls apart. The suspension could use some work, though; it sits a bit cockeyed up front. I wonder if I could find some used drop spindles somewhere?

Aww, the bodywork is "easy" and "fun", see my build thread!

Also, drop spindles are very available. These guys have some, made in USA, too.

http://gmcpauls.com/Suspension.htm

But if it sits cockeyed now, the drop spindles will not fix that. Likely you have a broken spring. I have seen that a few times.

MadScientistMatt
MadScientistMatt UltraDork
2/12/14 12:41 p.m.

That is my guess too, although the spring doesn't LOOK broken. Could be that it had one or two loops break off completely. The drop spindles are more of a "If I'm doing suspension work already..." sort of thing.

MadScientistMatt
MadScientistMatt UltraDork
2/24/14 2:15 p.m.

We'll be dyno tuning it soon - Russ Patrick, our ace tuner, will probably be handling this part, but I might take this one myself depending on our schedule. Can't wait to see what it makes.

MadScientistMatt
MadScientistMatt UltraDork
2/28/14 3:57 p.m.

Found the transmission starts to slip if held at high load for a long period of time on the dyno. Guess that TH350's towing days are over - or maybe it just needs an aux cooler?

MadScientistMatt
MadScientistMatt UltraDork
3/7/14 3:20 p.m.

Had a front U-joint bearing decide to leave just before I got to work yesterday. Got the U-joint fixed and also welded in an extra set of exhaust hangers on each side as the failed U-joints had rattled off the nuts holding the pipes on.

MadScientistMatt
MadScientistMatt UltraDork
4/9/14 1:10 p.m.

Big thanks to GRM for selecting this one for the "Hot Builds" feature!

Had to patch an odd leak - I'm wondering if some 5/8" heater hose I got was actually 5.5/8" as it slid very loosely onto the heater core, and no amount of tightening the hose clamp would make it seal. Currently fixed by using a 5/8" to 1/2" adapter - but it took a lot of liquid dish soap to get the 1/2" hose to slide over the core fitting.

Remaining swap related things on my to-do list:

  • Get the speedometer working correctly.
  • Attach the kickdown linkage to the throttle body.
  • Yes, I'm going to put in a rear mounted gas tank, preferably something I can score at a junkyard instead of paying $200 for a new tank. Yeah, I'm feeling cheap.

I'm also pondering whether an add-on transmission cooler will make the TH350 hold up properly for dyno tuning. My guess is that holding it at constant RPM at 70% (or more) throttle is building up too much heat.

tuna55
tuna55 PowerDork
4/9/14 3:21 p.m.
MadScientistMatt wrote: Big thanks to GRM for selecting this one for the "Hot Builds" feature! Had to patch an odd leak - I'm wondering if some 5/8" heater hose I got was actually 5.5/8" as it slid very loosely onto the heater core, and no amount of tightening the hose clamp would make it seal. Currently fixed by using a 5/8" to 1/2" adapter - but it took a lot of liquid dish soap to get the 1/2" hose to slide over the core fitting. Remaining swap related things on my to-do list: - Get the speedometer working correctly. - Attach the kickdown linkage to the throttle body. - Yes, I'm going to put in a rear mounted gas tank, preferably something I can score at a junkyard instead of paying $200 for a new tank. Yeah, I'm feeling cheap. I'm also pondering whether an add-on transmission cooler will make the TH350 hold up properly for dyno tuning. My guess is that holding it at constant RPM at 70% (or more) throttle is building up too much heat.

My new gas tank for under the bed was around $100. Most JYs these days poke big holes in the tanks, so you're out of luck there.

MadScientistMatt
MadScientistMatt UltraDork
4/9/14 3:30 p.m.
tuna55 wrote: My new gas tank for under the bed was around $100. Most JYs these days poke big holes in the tanks, so you're out of luck there.

Hadn't realized that as I hadn't started looking - but you're right, it appears that's the case around here too. Thanks for the heads up.

MadScientistMatt
MadScientistMatt UltraDork
4/9/14 3:48 p.m.

That's a Blazer tank, right? Where did you find one for $100?

tuna55
tuna55 PowerDork
4/9/14 4:10 p.m.
MadScientistMatt wrote: That's a Blazer tank, right? Where did you find one for $100?

Blazer tanks hang too low for my tastes, and I wanted something that I could use exhaust tubing for my fuel filler, so I used a Jeep tank. Search JP1A, it's for a 73-76 CJ, but all of the CJs fit to some degree, mine just has a bigger filler opening. I bought mine on ebay here Tank and it was $85. I then bought and modified Blazer straps for the bottom (had to cut a few inches out of the middle and weld the pieces together) as well as the Jeep straps (which go along the side) to mount it in place. It sounds weird, but it worked great and looks factory. Here are some pictures.

There are lots more around page 46 of my build thread

http://grassrootsmotorsports.com/forum/build-projects-and-project-cars/build-thread-for-the-72-gmc-finally-thanks-john/59103/page50/

tuna55
tuna55 PowerDork
4/9/14 4:12 p.m.

Only one caveat to the jeep tanbk, the sender will be wrong. It can be fixed, though. There are ways. You can retrofit a blazer sender onto the jeep supply tube.

Here is a picture of the side straps.

MadScientistMatt
MadScientistMatt UltraDork
4/10/14 9:58 a.m.

Thanks! That also seems to be a better price than what I've found on Blazer tanks.

MadScientistMatt
MadScientistMatt UltraDork
4/11/14 1:11 p.m.

Also, do you have any more info on putting the Blazer sender in the Jeep tank?

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