Dare I say it...Another 72 K5 build! The Bubba build - getting back into it

[bp71k5]

Either fuel pump option will require a return line. I modified my stock sending unit to add a return port and used an inline pump, or you can add a TEE from summit racing to the fuel filler hose to return the fuel. Other option is a fuel cell.

 

[gotblazers]

those rockers and doors are ****ing cherry. Why would you ever replace those. Also im pretty sure im the only one to finish reading the entire first post ive been practicing, it was quite a marathon .

 

[Z71paramedic]

Freakin TPI...

Well, turns out the damn thing is a 305. Now I'm again back-stepping and trying to figure out what all I'm gonna do. Still waiting on parts I've already ordered also...

As for the tuned port, I really want to run a TPI setup, so that will happen. I'm not sure yet if I'll cut down the factory harness I have or just buy one. I'm going to play around with it and see what I find. As for the intake itself...I was reading in the book I have (Chevy TPI swappers guide) and saw something about 87-up units had a different bolt angle on the center holes to the head. Just trying to confirm if that is true so I can figure out if my existing heads (in the truck now) will work with this setup. I know I need a different knock sensor and different injectors and had planned on replacing them anyways. I also know that I need to buy a VSS because it's a speed density system and then get a chip burned. Aside from these things and the fuel pump/lines will I run into any other issues using the existing 350 + .030 block/pistons and possibly heads that I have? Also, I know my block is an older style with 2 piece rear main. Is there a big enough advantage to the newer style that I should be looking for a new bottom end? Thanks again for the help guys.

 

[Greg72]

4X4HIGH would know all that kind of info.....

Asking him is better than any book I've ever seen, he's like RainMan when it comes to engine knowledge.

 

[Z71paramedic]

4X4HIGH would know all that kind of info.....

Asking him is better than any book I've ever seen, he's like RainMan when it comes to engine knowledge.

Thanks Greg, I'll do that. I'm just trying to get everything laid out before I tear a running/driving truck apart. I'd like it to be off the road as short a time as possible. I know I'll find more stuff once I get into it, but to have most of the big stuff ready should help.

 

[fatdog]

Yes the 87 and up heads have a wider pattern on the center intake manifold bolts. If your TPi unit is speed density and hasn't been converted from a MAF unit it should have the wider bolt pattern. I have heard you can drill the manifold to fit, but I've never done it or talked to anyone who has. Your options are to run a newer style head on the 72 block, drill your manifold, or if you want to run the pre-86 heads without drilling the manifold, you can run an 85 or 86 TPI manifold. I just happen to have an 85 manifold if you want it. Just pay the shipping.

I just did a TPI swap on my 72, and I used an inline pump from summit. I mounted it on the inside frame rail near the tank and spliced into the existing fuel line. it cost me $80 and it is working great so far.

I used MegaSquirt for the electronics without a VSS and without a knock sensor and built my own wiring harness. I also eliminated the EGR stuff because I don't have any emissions to deal with. It really wasn't a difficult swap, I took the winter to do it. I could have done it in less time, but I didn't need to. It and starts and runs great and is completely tunable using a laptop. I wanted to keep it as simple as possible so that's why I went the way I did.

 

[Z71paramedic]

Yes the 87 and up heads have a wider pattern on the center intake manifold bolts. If your TPi unit is speed density and hasn't been converted from a MAF unit it should have the wider bolt pattern.

It is speed density, and everything harness-wise seems original. It's out of a 91 T/A

Your options are to run a newer style head on the 72 block, drill your manifold, or if you want to run the pre-86 heads without drilling the manifold, you can run an 85 or 86 TPI manifold.

Yeah, I'm pricing newer heads now. Rebuilt 193's are going to cost me @$350 Not too interested in re-drilling, just in case I fubar it all up...

I just happen to have an 85 manifold if you want it. Just pay the shipping.

Interesting.... Do you know if I'll run into any problems with my runners/plenum with an older baseplate? In that book I have it said to try to keep everything from the same setup. I'm not opposed to it, just want to make sure it will not cause me more headaches.

I just did a TPI swap on my 72, and I used an inline pump from summit. I mounted it on the inside frame rail near the tank and spliced into the existing fuel line. it cost me $80 and it is working great so far.

Pretty much the route I was planning. I don't think I feel like removing my sending unit and drilling it making metal shavings around something as sensitive as a fuel pump. Plus the brazing of something that has been submerged in gas doesn't sound like the best plan.

I used MegaSquirt for the electronics without a VSS and without a knock sensor and built my own wiring harness. I also eliminated the EGR stuff because I don't have any emissions to deal with. It really wasn't a difficult swap, I took the winter to do it. I could have done it in less time, but I didn't need to. It and starts and runs great and is completely tunable using a laptop. I wanted to keep it as simple as possible so that's why I went the way I did.

I wasn't certain if I needed the VSS or not. I wasn't opposed to it, just didn't know if it could regulate itself without it... Also wasn't sure on knock sensor. As for the EGR I don't need one (no emissions here either) but I was just curious if it made any difference to longevity of parts or runability? If I don't need it I won't be running it. I don't want any more crap on there than necessary. When you made your harness did you cut down a factory harness from a car or just buy new connectors and run only what you needed? Also, what type of O2 sensor are you running? I plan to cut down the one I have. No sense in spending $300-$400 more on something I can make. My time is free (relatively).

Thanks again for the help guys

 

[fatdog]

I'm not sure how this quick reply will tun out, I can't do a post preview, maybe because of my OS...so here goes, I hope you understand it.

It is speed density, and everything harness-wise seems original. It's out of a 91 T/A



Yeah, I'm pricing newer heads now. Rebuilt 193's are going to cost me @$350 Not too interested in re-drilling, just in case I fubar it all up...

I guess it all depends on what you want in the end and what you have to begin with. I think $350 is a fair price for a rebuilt set of SB heads. I've heard the 193's are good torque heads and good to around 5000 RPM. That would work well with the TPI because it's good to about 5200 RPM. Combined with a cam that has has...oh say 1200-5200 RPM range this would make a great truck engine, which it just so happens that's what you need. BUT...you knew this was coming...how good is your current 350's bottom end? Are you planning an overhaul of that also? If it is good with acceptable compression, I wouldn't hesitate to put the heads on it. However, if it's tired and already using a bit of oil, new heads could make that situation worse.

Interesting.... Do you know if I'll run into any problems with my runners/plenum with an older baseplate? In that book I have it said to try to keep everything from the same setup. I'm not opposed to it, just want to make sure it will not cause me more headaches.

I can't remember all th differences between the base plates, but I know the 85 has provisions for a cold start injector, so your runners may not work on it. Honestly, when I was researching my setup, I found out most people were converting the MAF units to MAP units, so I think I'd stick with your complete 91 setup and just swap heads.

In my case, I had a 98 vortec 350 lying around that needed an overhaul, so I just used it, because I had it. However to make the TPI work with the vortec heads, I had to buy a custom baseplate from SD at a price of $400 The only way I could justify that was I paid nothing for the vortec longblock, and I got it completely rebuilt with new pistons for $1200.

Pretty much the route I was planning. I don't think I feel like removing my sending unit and drilling it making metal shavings around something as sensitive as a fuel pump. Plus the brazing of something that has been submerged in gas doesn't sound like the best plan.

I also ran a return line down the drivers side frame rail and spliced into the filler spout hose. I used 5/16th brake line available from the local NAPA store. I primed the pump before starting the engine using compressed air in the gas tank filler spout.

I wasn't certain if I needed the VSS or not. I wasn't opposed to it, just didn't know if it could regulate itself without it... Also wasn't sure on knock sensor. As for the EGR I don't need one (no emissions here either) but I was just curious if it made any difference to longevity of parts or runability? If I don't need it I won't be running it. I don't want any more crap on there than necessary. When you made your harness did you cut down a factory harness from a car or just buy new connectors and run only what you needed? Also, what type of O2 sensor are you running? I plan to cut down the one I have. No sense in spending $300-$400 more on something I can make. My time is free (relatively).

I've heard you can run GM electronics without a VSS, but I've also heard they don't run all that great without it. I don't know for sure because I haven't tried it.

EGR and longevity...i'm really not familiar enough, but it doesn't seem like re-introducing exhaust gases into the induction air would do any good whatsoever. Maybe only for an emissions test, but even then you'd have a hard time convincing me it actually helps the environment. A well tuned engine is what really helps with emissions, I think. If I have a choice, I'll take fresh air for intake air thanks.

Like you, I didn't want any more crap on there than necessary either...and just as important, I wanted full control when it came to tune-ability. I didn't want to implement the ability to burn chips, and I didn't want to have to shell out a couple hundred bucks every time I needed a new chip because the "one I just had burned wasn't quite right." Hence the reason for running MegaSquirt.

For the wiring part I used a labeled wiring bundle that cost me $40. I also used a relay board to make the wiring easier, and I wired it ...one wire at at a time...pretty soon, I ran out of wires and everything was wired.

Please keep this in mind, any FI project will turn into more than you think... work and expense. Mine was not inexpensive eventho, I had most of the hardware part lying around waiting to be used. However, the cost has already been forgotten now that I'm enjoying the benefits. I'm not done by any means, I also did the 700R4 241 swap and I'm still dealing with drive line angle vibrations, cross members issues, gearing issues, rather to stay 12 bolt or go 14 bolt and .....but everytime I solve a problem I'm that much closer to having the K5 I want and i'm

I'd be honored to help you or any other member of this forum out if i can.

I'm in the process of switching my operating system to Linux...so as soon as I get it all figured out I'll post some pics.

Thanks again for the help guys

 

[fatdog]

Also, what type of O2 sensor are you running? I plan to cut down the one I have. No sense in spending $300-$400 more on something I can make. My time is free (relatively).

Oops forgot to answer this question. If you're running headers it probably should be a heated sensor anyway. I chose to run one made by Innovate Motorsports. It's the LC-1 and it's a wide-band sensor. I run it with an AFR gauge for tuning purposes.

 

[fatdog]

Damn...I don't think there's anything wrong with my OS or browser, it's me. I just can't get the quote buttons figured out I guess.

 

[Z71paramedic]

Damn...I don't think there's anything wrong with my OS or browser, it's me. I just can't get the quote buttons figured out I guess.

Don't feel bad, it took me a few tries to figure out the whole multi-quote thing.

Thanks for the input. As for the bottom end of mine it runs super strong. The only reason I was initially thinking of rebuilding the whole thing is that it was going to be out, and as Greg would say....Might as well. Then I found out machining was going to cost me a TON out here (freakin Hawaii, I can't wait to get back to the mainland BTW) so I decided I could just do a rear main/oil pan gasket, cam & lifters and then whatever I decided with the top end. Then I stumbled into this TPI setup. It burns/leaks some oil but I think the burning is just valve seats. I had my valve covers off a while back and it wasn't too perty under there But like I said it runs strong... I'm not looking to have 500hp or anything. Mid 300's with good to awesome torque would suit me fine. In fact EFI with the power level I have now would be fine. I'll keep you guys updated as I figure out which route I'll be taking. Then 4-6 weeks later when my parts show up I'll be happy...

 

[Z71paramedic]

Holy crap, I actually started...

Well, I guess I'm committed now...

So I actually started this last weekend but didn't finish with paint until today so that's why I didn't make a post (didn't want to make one with no pictures)

The PO was a POS! When installing the body lift he didn't feel like buying bumper brackets to raise the bumpers up soooo apparently it was a good idea to cut the front frame horns off and move them up and weld them in place *poorly*

So I took off the front bumper and grille to start there, it seemed as good a place as any. Passenger side wasn't a big deal. Just a lot of ugly welds to grind off. Then I started looking at the drivers side. I knew the frame was a little bent on that side from a wreck who knows when. I didn't realize it was as F*d as much as it was/is. First of all it was cut and moved as well. But then it was missing a fair amount of material that the PO just cut off because it was bent. After removing the ugly old welds and doing a lot of heating and beating I got it to where I'm ok with it. Then measured and measured and measured util I got it clamped where it needed to be and tacked it in place. I ended up using some of the angle iron I cut off to bridge the gaps on top and bottom and welded the Sh*t out of them. Then filled in the smaller gap on the side with my welder's helpers from eastwood. They worked awesome btw. After a heck of a lot of grinding later I called it a day. I got off work too late every day to really do anything during the week so today I finally got the chance to Por15 the frame from the spring hangers up and my new parts from DIY4x that showed up a few days ago. I'm very pleased with the passenger side but the drivers side leaves a bit to be desired. I'm sure it's strong enough but it's ugly...

Anybody have a donor frame that they want to cut the front off of??? I'll pay you and handle shipping obviously. Let me know

Now tomorrow I get to do the rear bumper... It shouldn't be that bad though because instead of cutting the frame he just welded long plates from the bumper along the frame. I'm hoping I can sawzall most of it off then just grind it smooth and repaint. I'm sure it won't go nearly that smoothly though. We'll see

 

[Greg72]

Mahalo!!

Hey....before you get too much further, tell me something: Are you planning to remove the bodylift as part of your process??

If not, I have some bad news for you. The lower part of the bumper is going to hit those frame horns and prevent you from bolting it up correctly.

I learned that one the hard way too back when I had a 2" body lift. You can cut two notches out of the bottom of the bumper to let the frame horns poke through, but that ends up looking pretty bad (I tried it).

Ultimately, I think the best solution is to cut the frame back with a nice square cut, then fabricate a competely new mounting scheme to hold the bumper at the correct height. I can post a pic of how I did it on mine if you don't mind someone else's photos in your build thread.

Sorry for the bad news, but I couldn't let you spend an entire day on the rear bumper without at least warning you about some potential setbacks.

Good Luck.

 

[sponsoredbydad]

Well that just goes to show ya, It doesn't matter how cool it looks chances are somebody before you has hacked it together. Guess I just got lucky and my PO was a lazy s.o.b. Great fore thought Greg that's the kind of info that makes this site so bitchen.

 

[Z71paramedic]

Good call Greg Actually that is in the works, my plan is to get the frame right and then remove the body lift and replace it with new body mounts. Then to recover for the lost height add more suspension. That will be a DIY4x shackle flip on my current 4" springs and zero rate in the rear and new 6" springs in front with a zero rate and possibly longer shackles (plus a shim to correct caster). I have all the stuff for the rear but still need to bite the bullet on the front springs and whatnot. I'm also going to build new bumpers, but that's down the road a touch. It may come after getting it running and driving again. Now it's off to cut the rear bumper off...

I actually just got back from a quick drive to the North Shore... Another fantastic craigslist find behind me. I got a Never used GM hood for $150. Not even worth tinkering with my current hood for that price! Hopefully I can sell my old one and make some $$$ back

And one more to show that I've actually started!

 

[Z71paramedic]

Don't get too excited, I haven't made any real progress...

So I haven't really done anything on the truck in a bit since I'm still part-searching and all that good sh**. I'm still trying to figure out what all is going to be the end result with the engine, so nothing happening there. I never cut the back bumper yet because I haven't got enough parts to complete any "section" of the truck and at this point I could still drive it if I put the grille and bumper back on. I keep getting my a$$ handed to me on shipping (approximately 1/3 of the money I've spent so far has been shipping). So that's putting me behind even more. And on top of everything else I've had three separate occasions where someone quotes me a good price on something I want/need and when I tell them I'll take it they stop communicating with me...

So I suppose in the mean time whilst waiting for stuff to show up *decisions included* I'll ask a few more questions:

I got a quote from Alcan for $570 just for front springs not including shipping. Normally I would've just laughed and gone a different direction, but for rough country ez rides + shipping and the cost of the zero rate + shipping I was going to run I'm pretty damn close to that mark. Are the Alcan's worth the extra coin?

Next: When I pull the windshield, how might one go about removing the chrome without damage? And I guess while on that subject, what's the best way to remove the weather stripping without harming the windshield?

How does the dash mat come off? I know there are clips under it, but I don't want to try to force something that's almost 40 years old...

I think that's all I've got right now. Maybe I'll actually start doing some of this stuff soon, we'll see

 

[Z71paramedic]

Dammit

I knew I'd forget something, my master cylinder leaks like crazy so obviously that's on the to do list. Should I go stock 3/4 ton, or a newer setup, or...??? Any suggestions
FYI it actually stops pretty darn good now, but obviously with more power, I could probably use more stopping. Let me know

 

[Greg72]

If you're buying a new window gasket, just cut the old rubber one back to the edge of the trim, then carefully pry it out. You'll ruin the rubber seal (cheap) but save the chrome trim (expensive).

Alcan makes good springs...but the end result of a custom spring is only as good as the information you provide to them. Accurate weights of everything will be important (sprung vs. unsprung)...and if you plan to add a winch, or heavy bumpers you need to tell them. If you plan to tow a load, you need to plan for that also.

Dash mat is attached with a series of molded-in studs across the front edge, with about 10 sheetmetal nuts holding it in place. There is probably a photo in the early part of my build thread that will show you the dash with the pad removed. You should be able to spot the holes where the bolts were.

 

[Z71paramedic]

Thanks on all three of those Greg, I'll take a gander (heh, gander) through your build and see if I can't find the pics you're talking about.

I really need to figure out which front springs I'm going to run and just buy the damn things. I can't get the body lift out without more suspension lift, I can't (or don't think it's a good idea to) start sheet metal repair without the body sitting where it's supposed to... and I don't feel like taking it apart the rest of the way until I pull the trigger on some of this. GRRR

 

[Greg72]

Here's the pic I was thinking of:

If you look carefully at those slots you can see what look like little "speed clips" where the dashpad studs came through. They are spaced something like 8 - 10" apart.

There's one on each end, one centered above the gauge cluster, one directly above the ignition switch, one above the cig lighter, and one centered near the glovebox latch.


EDIT: Check that....the speed clips are for the underside dash screws. The studs come through from higher up, and really aren't visible in this photo.