1978 2wd Blazer
 

So I was looking at a 1978 2wd K5 Blazer about two weeks ago.

The PO bought it as a project, no motor or trans. He had a friend help with a motor swap that's supposed to be a 91 Camaro motor with new HEI, Edelbrock intake and carb. Has headers but no exhaust so I'm probably going swap for Ram Horn manifolds. No provision for a mechanical fuel pump. I'm leaning towards a factory EFI pump in the tank from a later model truck with a fuel pressure regulator in the engine bay. Was an AC truck that had all the engine bay AC parts removed. Supposed to have a rebuilt TH350. Someone covered it in flat black primer. New tires on 15" chrome smoothies. The plan is just clean it up and get it reliable....

Supposed to finalize the purchase on Thursday. I'll update with details and pictures.

Re: 1978 2wd Blazer
 

looking forward to the pics :)

Re: 1978 2wd Blazer
 

No joke, post em up when you can...

Re: 1978 2wd Blazer
 

Stole this picture off Google Maps

Re: 1978 2wd Blazer
 

Google capture again...

Re: 1978 2wd Blazer
 

Looks like a cool truck with lots of possibilities.

This is also why I hate google maps. Those are pretty close up pics ;).

Re: 1978 2wd Blazer
 

I should pick up the truck tomorrow. (well later today actually) If the motor is as new as I was told, there is no provision for a mechanical fuel pump. I need a better fuel system to replace the $20 parts store pump on the front frame rail. I am leaning towards a new Spectra Premium 31 gallon EFI tank and factory style in tank pump with an Aeromotive 13301 bypass fuel pressure regulator up on the firewall. I am in hopes that there is a fuel return like going back to the tank to facilitate the bypass regulator.

http://www.rockauto.com/info/22/GM14C_TOP_P04__ra_p.jpg http://www.rockauto.com/info/22/SP12..._P04__ra_p.jpg http://ecx.images-amazon.com/images/I/31M7R3SNP8L.jpg

Re: 1978 2wd Blazer
 

A few pics...

Re: 1978 2wd Blazer
 

the interior is a little messy...

Re: 1978 2wd Blazer
 

needs a good cleaning...

Re: 1978 2wd Blazer
 

Need to work on the wiring.... Anyone know what wire feeds power into the fuse panel from the battery?

Also, anyone know what years a can get a donor AC box for the firewall? 73-91? 77-80? Only 1978?

Re: 1978 2wd Blazer
 

Any airbox from 73-up will bolt up. I am sure there are a few differences, but they will all work. Looks like a good start.

Re: 1978 2wd Blazer
 

I can't shake the feeling that truck has been posted here before. Congrats. Is that an old round-eye Benz following the truck?

Re: 1978 2wd Blazer
 

That's my 1986 Mercedes-Benz 560SEL in Astral Silver over black leather... I'm selling the Benz to build the Blazer...

Re: 1978 2wd Blazer
 

Got the tank the other day and snapped a few pics. You can see the internal baffle for the fuel pump... The pump showed up before work but forgot to get a picture.

Re: 1978 2wd Blazer
 

Does anyone know if they make adapters to fit the connections on the fuel pump? This is from an 88 K5 and I would like to come up with something that uses the factory connection at the pump/tank and that I can rig up to the hard line. Need both the feed and return line. I don't want to run braided line. Either EFI rated rubber hose or the modern nylon type.

RockAuto sells another male connector for the feed line but I need the female end....
Fitting Attachment End 1 Male O-ring - M16-1.5
Fitting Attachment End 2 None
Fitting Size End 1 16 mm
Fitting Size End 2 3/8 In.
Fuel Line Connector Design Male O-Ring
Gasket Material Viton
Material Steel
Package Contents Steel Fuel Line Repair Kit - 3/8 In. X 18 In. W/16mm Fitting

Re: 1978 2wd Blazer
 

And finally the other end that will mate the Nylon line to the factory steel fuel and return...
Dorman part number 800-135 -- 3 pack of 3/8, 5/16 and 1/4

Re: 1978 2wd Blazer
 

Out with the old .. in with the new... well I didn't install the new tank yet. I'm going to see about getting it covered in Line-X. Black it out so you don't see it as much, added layer or protection and sound insulation.

Re: 1978 2wd Blazer
 

Nice! I'll be following along. I want a 2wd blazer so bad!

Re: 1978 2wd Blazer
 

Good info! Clean 'ol Blazer!

Re: 1978 2wd Blazer
 

SO they wanted $240 bucks to Line-X the thing....forget that... I talked to my powder coater. Was going to do a gloss black textured coating, but with the neck soldered in, they couldn't guarantee that it wouldn't be an issue when curing the powder coat in the oven... I'll either POR-15 the tank or just install as is...

Re: 1978 2wd Blazer
 

I could use some advice on a few electrical items.

1. The motor is out of a 91 Camaro and it has an electric oil pressure sensor next to the HEI. I believe the 78 was mechanical oil pressure. What are my options? (see question 2 first)

2. I am using an in tank electric fuel pump. Without an ECM to prime the pump, how do I set up a relay to the pump. I would like to incorporate the oil pressure sensor to control the fuel pump relay? Do I need two relays? One to prime and one to run?

Anyone recognize one of these part numbers for the oil pressure switch to operate the fuel pump relay?
OEM Part Number(s): 12353898, 1S6812, 2011345, 25036845, 25036938, 6000092, PS215

Re: 1978 2wd Blazer
 

Cool blazer. I think you are just needing one relay that stays hot with the ignition on. The tbi oil pressure switches duplicate the current coming from the relay in case of a relay failure the pump keeps going. I've never run an electric pump with a carb but assume it would work the same with a return style fuel pressure regulator.

Re: 1978 2wd Blazer
 

You can get a Painless harness for the fuel pump. it uses the oil pressure switch to control the relay. you need ignition voltage in the switch to the control side of the relay. the power side of the relay goes to the battery to the pump. if you want a prime you would need to add a push button from battery to the power side of the relay. I ran a holley blue pump for years and never had a prime. the only time I had an issue with it is from sitting all winter long. all I did was crank the enginr till it got oil pressure and then the pump would fill the carb. after that it was good to go. you still need to run a regulator in the system to knock the fuel pressure down to about 5 pounds.

Re: 1978 2wd Blazer
 

I have some Bosch relays so I'll just build a harness off keyed power. I was trying to over engineer it where it primes for 5 seconds and stops powering the pump till its running. Doesn't need it, but thought it would be cool.

I did find this.... http://www.revolutionelectronics.com/Fuel_Pump.html

I have the Aeromotive bypass regulator that I'm going to mount on the firewall. I have a 0-15 psi liquid filled gauge that will be mounted on the front of it. I'm upgrading fuel lines to late model GM style nylon line with a quick connect frame mounted fuel filter.


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