383 Vortec/TBI Build Thread

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skysurfer

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Search Summit for Walbro GCA710-2. It's the kit I installed in this thread.
 

Daveo91Burb

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Search Summit for Walbro GCA710-2. It's the kit I installed in this thread.

Thanks! I should have remembered to check your thread - I've seen it a few times and will definitely be accessing it when I tackle this job.

Do you guys think this Amazon listing is legit? It looks just like the pic on the Summit page, but don't want to take any chances. I guess I could just return it if there's any doubt. It's just so much easier/quicker/cheaper to order from Amazon......

https://smile.amazon.com/Walbro-GCA...id=1487297161&sr=8-1&keywords=Walbro+GCA710-2
 

skysurfer

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Well, Amazon is one of the places Walbro lists as a source of fake pumps. How would you know a real from a copy? I read some threads on other forums where guys thought they received a genuine pump only to find out after install it was noisy and died soon after the install. I didn't see that 710-2 kit on Walbro's site but I think calling them would get you what you're looking for.
 

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Yeah, I think you're right. I'll call them next week and get the scoop.
 

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Daveo91Burb

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Search Summit for Walbro GCA710-2. It's the kit I installed in this thread.



How did you determine GCA710-2 was the correct pump to use? I googled specs for it and came back with a pressure of 43 psi - seems way too high for TBI??? Did you do anything with the chip or computer? The way I understand it is if pressure is changed much from 13 psi-ish stock, need a new chip with modified pressure parameter.


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skysurfer

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The original receipt for mine is missing so I googled Walbro 190 and the only kit that matched all the same bits was the 710-2. I know the kit I installed was for Mustangs and so is the 710-2 so I took an educated guess that it's the same kit.

I'm thinking the 43 psi refers to the rating Walbro gives for a pump's continuous max output (100% duty cycle) which is then throttled back by whatever regulator you have. In my case, it's the Aeromotive afpr which came with two different springs for use above or below 18 psi. There wasn't any need for me to change the ecm's prom since I'm still in the 12-14 psi range and haven't changed engine displacement.
 

Daveo91Burb

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Thanks. Yeah, I'm pretty sure I'm going to have to go with some kind of regulator other than the one on the TBI now. Dang - those Aeromotive ones are not cheap. Although I am thinking about seeing if I can go through the process that this guy did:

TBI Mods/

In other news, I called Walbro yesterday and they agreed to match the Amazon price! They emailed me a code today to use when I place the phone order. But tonight I replied back and asked if they had any other suggestions regarding pumps with OEM pressure and higher than OEM flow rate. (Gave them my basic build specs). We'll see if they come back with anything.
 

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Well, Amazon is one of the places Walbro lists as a source of fake pumps. How would you know a real from a copy?
Just want to say that I've bought several things over the years from Amazon and their vendors, including a Holley carb and GM distributor for as much as 25% less than prices at Summit and Jeg's. And the good thing is if you don't get exactly what was advertised, you can return it on Amazon's dime and get full credit. Sometimes they will even tell you to keep the item, depending on its price or what their vendor wants to do. That happened to me with a Derale fan clutch, that turned out to be some private label part that didn't look anything like a Derale fan clutch. Got a full refund and kept the part.

And here's my favorite Amazon story: In December I paid $5 for 2-day expedited shipping to get a $45 bottle of perfume for my wife. When it arrived a day late, I asked the Amazon seller for for a $5 refund. But they end up crediting me the full $50! And that's not all. When I opened the box, I noticed that they had sent me the larger $80 bottle!

Apparently, the Amazon vendors are scared to death of bad reviews or upset customers.
 

MikeB

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On another note, I have used the CompCams Magnum rockers on several engines over the years. I suggest you try to find a thin-wall socket to use for valve adjustment, because the clearance between the cast rocker body and the nut is tight. Or you can use a name brand 1/4" drive socket (not HF junk), which has thinner walls than a 3/8" drive socket.

Another solution is to use Comp's poly-locks for pivot ball rockers, NOT the ones for use with roller fulcrum rockers. And be sure to check valve train geometry. If you're not familiar with the procedure, then google it.
 

Daveo91Burb

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On another note, I have used the CompCams Magnum rockers on several engines over the years. I suggest you try to find a thin-wall socket to use for valve adjustment, because the clearance between the cast rocker body and the nut is tight. Or you can use a name brand 1/4" drive socket (not HF junk), which has thinner walls than a 3/8" drive socket.

Another solution is to use Comp's poly-locks for pivot ball rockers, NOT the ones for use with roller fulcrum rockers. And be sure to check valve train geometry. If you're not familiar with the procedure, then google it.

Thanks for the input! I've never used the Comp cams rockers, but I've used the PRW ones that are very similar if not identical and had similar problems. Mine even had the poly-locks and I still had some issues. I think I used a 3/8 socket but I had to grind the outer diameter down a bit for it to fit. Can you even get a 1/4 drive socket in that size? Isn't it like 5/8"? I might try that if so.
 

MikeB

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Yes. Here are a couple of examples:

https://store.snapon.com/Deep-inche...et-Deep-5-8-6-pt-Blue-Point-reg--P646492.aspx

https://www.amazon.com/Stanley-J4720A-4-Inch-Socket-8-Inch/dp/B00BNGQNAG

Just ordered these for myself.

BLPLS1458 Socket, Deep, 5/8", 6 pt. (Blue-Point®) 5.35 USD
BLPLS1412 Socket, Deep, 1/2", 6 pt. (Blue-Point®) 5.35 USD
BLPLS14916 Socket, Deep, 9/16", 6 pt. (Blue-Point®) 5.35 USD

Blue-Point is Snap-on's "budget" line made in Taiwan, which to me has always meant much better quality that China.

Shipping was free, but for some bizarre reason they charge sales tax, which was approx 80 cents higher that what TX sales tax should have been. Thought it was a good deal anyway.
 
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Daveo91Burb

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Yes. Here are a couple of examples:

https://store.snapon.com/Deep-inche...et-Deep-5-8-6-pt-Blue-Point-reg--P646492.aspx

https://www.amazon.com/Stanley-J4720A-4-Inch-Socket-8-Inch/dp/B00BNGQNAG

Just ordered these for myself.

BLPLS1458 Socket, Deep, 5/8", 6 pt. (Blue-Point®) 5.35 USD
BLPLS1412 Socket, Deep, 1/2", 6 pt. (Blue-Point®) 5.35 USD
BLPLS14916 Socket, Deep, 9/16", 6 pt. (Blue-Point®) 5.35 USD

Blue-Point is Snap-on's "budget" line made in Taiwan, which to me has always meant much better quality that China.

Shipping was free, but for some bizarre reason they charge sales tax, which was approx 80 cents higher that what TX sales tax should have been. Thought it was a good deal anyway.

Thanks. I've got the Stanley one in my cart on Amazon now! Interesting, the picture of the Stanley shows "Proto Professional" on the side, I think Proto was one of the top names in American tools some time ago? I didn't know Stanley bought them, at least I'm assuming that's what happened. We'll see where it's made, probably China, I'm sure.....
 

Daveo91Burb

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In the process of buying a Walbro GCA710-2 fuel pump now, direct from Walbro's distributor. They price matched Amazon and regular shipping was still free so win win. (It will probably take longer than Amazon, but I'm in no hurry) I've also purchased a fuel pressure gauge and fuel line adapter so I can install it right at the TBI inlet location from R.V. Morse machine. I'll post pics when they get here.

Two questions:

1. Has anyone here ever done this mod to the stock regulator? I'm thinking of trying it since the JET and other adjustable regulators are not cheap. https://www.thirdgen.org/tbi-afpr/

2. For fuel pump install I'm thinking of cutting an access panel above the tank (it's a suburban and there's carpet back there) instead of dropping the tank. Any pitfalls to this method I should know? Is the pump in the exact center of the tank? I have an idea of how I will reinstall the cut-out panel to make it removable.
 

MikeB

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I think Proto was one of the top names in American tools some time ago? I didn't know Stanley bought them, at least I'm assuming that's what happened. We'll see where it's made, probably China, I'm sure.....
I have a few Proto tools that are 40+ years old. No doubt made in the USA back then.

Read on a auto mechanics forum that the Blue Point tools are very nice. Also, a guy I used to do part time work for has been buying Blue Point and even Tekton and GearWrench. He's got a gazillion Snap-On and MAC tools from 30+ years as a mechanic, but says the prices are killing him.

Personally, I've never had any problems with Craftsman tools, but I'm just a hobbyist. I do like Snap-On's semi-deep well sockets, but see where SK Tool and others also sell them.

Just want to add that the Taiwanese tools are light years better than the Harbor Freight low Chinese bidder tools. Maybe they're getting better, but back in the 1990s their sockets were total junk, and could round off a bolt head in nothing flat. Still remember using a friend's 1-5/16" socket that was closer to to 1-11/32". Not good when trying to break loose suspension bolts that had been torqued to over 100 lb/ft.
 
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