A few odd questions for a 1976 454 block going into a 1979 G30 Motorhome

[MuddiGGEr25]

I thought I already had a thread on here but if i do it wont come up on the search feature so here goes a new thread, and im sorry if i already started one:

https://www.facebook.com/media/set/?set=a.10207385731494293.1073741837.1016864859&type=1&l=322de1973d

First off that is a link to the album of my pics of my progress on this build and more will be added as I go until the engine is installed and we have made our Trucks Gone Wild trip in june, the album should remain up and public for many years so it can help others along the way.

Just a quick summary of the project:

1981 Fleetwood Tioga on a 1979 ChevyVan G30 Chassis with a 400 (6.6L) V8, TH400, and 4.10 14FF Rear Axle
83XXX miles currently on the rig
All of the following was done on or around Sept 2013 at approximately 80XXX miles
The Engine, Transmission and Carb were all overhauled, yes i have receipts
All 6 tires and the spare were replaced
Torque Converter was replaced
All Brake lines and Fuel lines were replaced and bled
All brakes were inspected and replaced and bled as necissary
Entire Exhaust system from manifolds back was replaced done as true dual with no H or X pipe
400W of solar panels installed and solar controller and 1500W grid-tie inverter installed
All interior lights replaced with LED


Now about 200 miles ago the PO got an oil change at some quick lube place, and wasnt watching the oil pressure guage and ran it dry, and drove it 50ish miles the next morning to a gas station before it seized up completely.

I am keeping everything except the 400 because I was able to trade the Generator for a 1976 454 almost complete was put into a 1986 mudding truck with only 70K on it before being pulled obviously no paperwork to prove this but only hearsay.

I did get the 400 removed today, not the most pleasant experience using only hand wrenches then having the cherry picker break a caster but anyways its out lol, I will put it in storage until this fall when I have time to tear down the bottom end and find out how bad the damage really is.

I did pickup a Thumpr Cam for the 454 on thursday however I am on a layoff and money is not on my side at the moment to do a breakin with new lifters and risk messing up. so the ThumpR cam has been delegated to go in the 400 when I have time and money to play.

I will be pulling the heads off the 454 after the T-Storms pass, probably late monday or early tuesday, I will be taking the heads, water pump, timing cover, intake, and valve covers to the parts washer at the shop i am laid off from because my boss is nice enough to let me still use the equipment.

I will add pics of all that before and after to the album so y'all can know which heads and pistons etc i have to work with.

I will  be using all NEW gaskets from the heads up from fel-pro and black RTV for the misc edges on the intake.

I am not sure how to set the base timing, I know I was "told" he changed the cam but i always tune the carb to max vaccuum then go lean 1/4 turn then advance the base timing until the vacuum doesnt increase anymore then back it off 1 in-hg and it always works for me, just wondering if this is actually accurate.

I am wanting to install a secondary Alternator on the block in the SMOG/AIR pump location, just wondering if this is feasible with some basic angle iron and a longer belt? I am fully aware that I can get a 150A 1 wire alternator on eBay for like $239 but I do not have that kind of cash around before june, and I have a brand new Reman 78A alternator that tested to putout 91A at highway RPM.  The reason behind this is this: I want to use the 2nd alternator to solely run the rear power requirements, i.e. the 400+Ah battery bank, the 12V lighting and fans, and the 12V-110V inverter while driving during the summer. I have a 8,000BTU High Efficiency Window style A/C unit that only uses 810W Maximum while the compressor is running and fan on HI, that is 1/2 of what the rooftop unit needs to cool the RV down, thats 800W AC so 900W DC current at 12-14V which comes out to around 75A 12V current, which the alternator can provide while travelling down the interstate, as well as the 20A-25A that the solar can put out anytime between 11Am and 5PM. So power requirements are not in question, I just need to know about running a 2nd alternator in that spot. As well as God forbid that the oem alternator would fail in the middle of the night or in the middle of no where, I could just have a switch wired to a relay that would route the 2nd alternator into the primary circuit


I also received a brand new TCi dual pattern flywheel for the 454 as a well as a OEM PS steering pump however the pump is not for a hydroboost system and i have read on a couple forums that if I T into the pump return line with a proper size brassT that it will still function just fine, can anyone chime in on this?

Another question I have is can i use the rebuilt quadrajet from the 400 on the 454? they both work but the 400 has less than 4000 miles on it and I was wondering if it might get slightly better mpg due to it running leaner because of it being jetted for the 400 not the 454? I understand running leaner would require any or all of the following: higher octane fuel, less total timing or less aggressive timing curve, more cooling capacity due to increased internal temperatures. Just wondering if this makes sense or not because of towing the suburban ~6,000lbs when loaded.




I am tired right now So I am sure i am forgetting some part of this project, but this is the jist so I can start getting some feedback before next week. I am on a timeframe to get this installed before the end of april because the landlord is down my throat about a non-running vehicle in the trailer park.

Our maiden voyage will be to Trucks Gone Wild in June 2016 2300 miles round trip and maybe some idling for keeping the AC running, idk yet.


Thanks in advance

[Stewart G Griffin]

1) Not trying to attack, but the post is confusing as heck.

2) As far as the carb:
It might work.  Smaller jets, if the jets really are smaller than most 454 carbs, (have we confirmed this?)  do not necessarily mean more mpg.

Who "rebuilt" this carb?

In sum, i would stop messing with used parts unless you know how and can rebuild them properly.  If you cannot afford new parts, then you can't afford the truck.  Simple as that.  Not trying to attack either.

[fitz]

The Thumper cam you got for the 454 won't fit the 400.

[MuddiGGEr25]

1) Not trying to attack, but the post is confusing as heck.

I apologize, just let me know whats confusing so i can try to explain it better, I have adhd and aspergers so i do my best to make sure things come out the way i mean them too.

2) As far as the carb:
It might work.  Smaller jets, if the jets really are smaller than most 454 carbs, (have we confirmed this?)  do not necessarily mean more mpg.

Thats what I was trying to get a consensus, and yes I have paperwork, i.e. receipts and part numbers from the 2013 rebuild of everything at 80XXX miles, which was only 39XX miles ago, and just under 3 years with occasional use.

Who "rebuilt" this carb?

In sum, i would stop messing with used parts unless you know how and can rebuild them properly.  If you cannot afford new parts, then you can't afford the truck.  Simple as that.  Not trying to attack either.

as i just said, i have paperwork on all parts and labor done by the shop in california, and I can quite honestly say that after working in 2 major diesel/farm equipment shops, and 1 automotive and 1 transmission shops here in town, we have a much higher failure rate for NIB parts from NAPA and O'reilly VS our used stock on the back shelves.
 And im my personal experience used authentic GM parts take much more abuse and last much longer when maintained identically to NIB chinese crap. just my experience.

I am messing with used parts because I have a bad back, damaged tissue in both knees and adhd, anxiety, and asbergers, and working full time is a chore at best, especially if customers are involved, but i try my best, i am laid off due to work shortage right now but that should change in the next few weeks, but I am in a time crunch because of the rules in my lease I only have xx days I can have a non operational vehicle in my driveway and its been raining nonstop for about 4 days and going to continue for another 2 before i have a decent day again.

The Thumper cam you got for the 454 won't fit the 400.

Yeah I just realized what I said last night, i was tired as heck so yeah, dont know what i was thinking when i wrote that, must have been thinking of the pontiac 400 big block or something lol

[MuddiGGEr25]

Well rain finally stopped, got the headgasket set and exhaust manifold bolts coming tomorrow at 8am, temps are 50,53,54,56 for highs the next 4 days, and tomorrow is supposed to be sustained 25-30mph -.-  I will be pulling the intake and hopefully the heads today once it reaches 50 lol its only 36F right now .   I will get lots of pics of casting numbers and as I go and add them to that album when i come inside.

[MuddiGGEr25]

ok i lied, i decided im not pulling the heads because it appears to have fresh intake and head gaskets, and i dont feel like risking screwing something up when i go to torque the head bolts or the rockers so im leaving well enough alone, it looks immaculate down into the valley where i can see the new cam, and through the "peekhole" i can see a new steel upper timing gear and the chain appears to be a double roller so i will leave that alone too.

Going to stop by my old workplace and ask if i can run the valve covers, intake, and engine mounts through the parts washer real quick. they are grimy as all heck.

My intention is to get the flywheel on it tomorrow and get the block mounted to the trans and to the RV frame, probably going to attach the exhaust manifolds before sliding it in. then attach the intake, carb and accesories once its already in. i figure it will be lighter and taking up a little less actual space so maneuvering it should be easier i think.