Questions regarding my 1978 Avanti

[Mike Hill]

Thanks Bob

Great comments and advice. The SBC 350 is now out of the car. It's amazing what you notice when there isn't a big cast lump filling the hole....hoses and fittings that need attention. The list gets bigger!

The heads apparently are low compression. My mechanic (40+ years on V8/building race motors...he races an ex USA Samurai 240Z) thinks 8.5:1 which would be fine for our regular gas. He is looking at some more performance based 327 heads which he thinks would give 9.8:1. He is also looking at cam options too.

He has also carried out a leak down check and #5 needs some attention too.

The front springs have had spacers put in them. Is that legal in the USA? Over here the car won't pass fitness checks with them. Are the springs the same as the original Avanti? I ask that, as there maybe some in the Studebaker Club parts shed :-)

Cheers

Mike

[Gunslinger]

The springs are the same as the Studebaker Avanti.

Spacers...are you talking about the small, twist-in spacers between the coils? If so...no they're not stock. Someone added them to make up for sagging could springs. My '70 had them installed when I purchased it...new coil springs are the proper way to fix the problem. If the spacers you're talking about are the ones that the coils sit in on the control arm, they're stock. They were installed in a/c equipped cars.

You should look into the cost of a crate engine compared to rebuilding your original. By the time you include the machine and labor costs of a proper rebuild...especially with higher performance parts, you could well exceed the cost of a crate engine already built to the performance level you're looking for. You can buy a "turn-key" crate engine with intake, carburetor and all the bells and whistles that only needs to be installed, or a crate engine that you can pick your own intake, carb and other accessories.

[Avanti83]

Mike

As Bruce and I said earlier a crate engine is not a bad idea if you need to rebuild your current engine.

If you just want to change the cam be sure the builder matches the compression ratio and the cam. 8.5 with the correct cam can make a pretty good setup. If you want higher compression the 9.8 should work depending on the quality of pump premium in your area, then you'll want a different cam. Be sure he also knows the "Quench" for an SBC. IIRC they really like about 35 thousands and if you change heads "or keep yours actually" it's an important number for both performance and ability to not ping. There are usually enough head gasket choices to get it close.

For reference http://www.camaros.net/forums/showthread.php?t=124935

As far as springs, you have the answer from Bruce. Just for info - Your SBC engine/trans set up is 100-200 pounds lighter than the original Studebaker combo.

I'm glad you pulled the engine, a lot of good things can happen when you can clearly see what needs help.

Good luck, Bob

[plwindish]

Mike, as the artists say, you now have a blank canvass to work with. Clean up all the years of accumulated grease and grime in the engine bay so it'll be ready for whatever you put back in, be the original or a crate. Your budget will determine that. As I said earlier in a post, I had the 400 in my '76 rebuilt to keep it original. It was most likely more expensive to stay original when I had the machine/engine builders tear everything completely down, clean and build it back the right way. Today's crate motors are very reasonable and the cheaper way to go if you're not hung up on keeping it original. When I see what one can get a new crate LS complete with computer, wiring and etc for, I'm thinking I should have gone that route. Today's fuel injection take all the carb related issues away! I now have over 18,000 miles on my car since the rebuild and there have been some "bugs" that have gotten worked out, such as the builders hooking the power supply for the electric choke to the coil for its power. Now I'm on the 3rd coil and hopefully, rid of backfiring that occurred at the Colorado Springs last year 1100 miles from home. I'm not anticipating doing any more engine swaps with this car, so it will stay with the 400 it was born with. If I had it to do again, I'd really think about about doing the LS.

[GlennW]

Are folks sure there were years with no gelcoat? Molding without gelcoat is brutal on the molds and the porosity one often gets on the surface of the finished part is such a pain in the butt to prep & prime over that any monetary savings on skipping the gelcoat at molding would surely be eaten up later with increased material & labor in the paint dept and decreased mold life.

[Mike Hill]

Thanks Guys.

It certainly has been a blank canvas. Mega grime and gunge has been removed from the engine bay. My mechanic has uncovered a few engine issues. I think it's called "a voyage of discovery". The sbc has needed a new set of pistons as three of the originals had crown damage. He thought it looked like a manufacturing fault. The bores are good with std pistons only required. I have also needed to replace heads and cam. Maybe going down the crate motor route might have been a better option, but I'd already done some work so it's no turning back.

I've used the cast heads off a new crate motor...owner wants alloy. This will keep the CR respectable as the new pistons were higher CR ones. Also keeps my budget down.

Ages ago I asked about headers and "block huggers' seemed to be the answer, or Dorman std repacements. I'm looking at a set of block Huggers with the central two pipes going behind the other two. Is this the right type?

Cheers

Mike

Edited July 23, 2014 by Mike Hill

[Avanti83]

In a 78 engine needing to replace the pistons is call a gift. This now gives you the opportunity to actually put together a set of components that will bring the SBC back to life as before the emissions parts these years used.

You can now match the cam to the CR and get the performance that will make the car much more fun to drive. I would have recommended Aluminum heads as they cool better, allow a bit higher compression and flow better but as you have a set of cast irons ones just go with them and do a good valve job and, maybe match the ports if you are so inclined. That's what I've done on my 74 383. Head work will make a difference but I wouldn't spend a lot on the mods.

Instead of going all out on headers, remember the OEM Ram Horn style flow very well for a stock setup and fit what you have for a exhaust system.

If you are going with your stock exhaust system use the 2" and get it on the road. If you are replacing everything then go 2 1/2".

I just can't get excited about adding headers as there will be little to no gain in performance and there will be a bit of cost upside. Secondly, cast iron holds the heat better than header and takes it away from the engine compartment through the exhaust. I say this as the owner of two pretty stout SBC's and the header trip is just not high on my needs list. Also, wrap the pipes to help keep the engine bay heat down.

I'm not down on headers, I have them on my 54K SBC powered but I'd just like to spend on better improvements.

My 74 2 1/2" exhaust system.

Bob

Edited July 23, 2014 by Avanti83

[Gunslinger]

If you decide to go with headers, this should answer your question on block hugger types...

[Avanti83]

Bruce, if you can would you post a shot of the drivers side. Those are exactly what I would design to clear as they closely follow the OEM path.

Nice, Bob

[Gunslinger]

Here ya go...

These photos are several years old...different valve covers now as well as a different master cylinder and brake booster but you can still see the header installation.

[Avanti83]

Certainly an excellent fit in an SBC powered Avanti, Ceramic coated?

Secondly, custom head pipes or do the OEM fit?

Bob

Edited July 24, 2014 by Avanti83

[Gunslinger]

They're Sanderson ceramic coated. The speed shop that installed them also fabricated the exhaust system rather than source a prefabricated kit so I really couldn't say whether stock pipes would bolt up. I had 2 1/2" pipes run all the way back with Magnaflow mufflers.

[Mike Hill]

Thanks guys (Bob and Bruce)

The headers I'm looking at are the same with the central piping going behind the two outer pipes. I was impressed by the underbody shot of your car and exhaust system Bob. Thanks Bruce for your sharp pics of the headers. The valve covers looked impressive too. Did you have that Avanti logo etched on?

In regard to the motor specs, I'm hoping that my "post" smog SBC will provide a "pre" smog performance. I haven't intended for it to be built into a pavement shaking rocketship, but rather a punchy strong street motor. I don't want to scare my good lady too much (...or myself :-)

Appreciate all the excellent advice. I'm going to copy your trunk lighting idea.

Hope you're enjoying summer

Cheers

Mike

[Avanti83]

Mike

Pre-smog SBC's aren't Hemi's nor BBC's power wise but unless you have driven them you won't know how nice an engine they are. They rev quickly and there is just a effortless feel to what they do. That was totally lost when the emissions era hit.

Your's should recreate that and you and the wife should be happy with it. Good choice.

Best, Bob

[Gunslinger]

The valve covers looked impressive too. Did you have that Avanti logo etched on?

Hope you're enjoying summer

Cheers

Mike

The speed shop that installed the engine did those valve covers...they bead blasted the logo onto the covers. I eventually decided I wanted something different and had these valve covers laser-engraved and like them much better...

The photo isn't from the best angle but are far better than the bead blasted earlier valve covers.

If you do that SBC right, you'll have all the performance out of it you can reasonably hope for. Mine does more than I need...I'm not 25 anymore.

[Mike Hill]

Hi Guys

It's been a while since my last post in late July. The SBC is just about to head back into the repainted engine bay. The replacement parts to the SBC have all added up to a fair sum...the crate motor may have been a better route as people said, but some replacemnts were a late discovery.

I have painted the block Chevy orange. Were the front pulleys black? What were the original valve covers? I have a set of ribbed ones.

I have to re glass the body under the battery. Did they have any form of drain holes or a custom fitting tray? Mine had nothing just a hole where the battery acid had eaten through.

Cheers

Mike

[Gunslinger]

I can't say what the pulley colors should be but they were likely black. I don't believe there was any attempt by GM to color match pulleys but one never knows.

The ribbed valve covers may have been original...my '70 originally came with them. They're usually referred to as Corvette "LT-1" or "L-82" valve covers but it's not uncommon to see them on other Chebbies of the era. They're a very nice looking design and are available as reproductions on Corvette supplier websites. If you find polished versions rather than as cast they make for a mighty sharp appearance.

There was no custom fitting tray under the battery...a surprising oversight in the Studebaker design. Maybe it was simply another cost saving measure by a cash-strapped Studebaker. You can buy a support from Nostalgic Motors that provides more solid battery installation.

[boogieman]

On my '79 the pulleys are black. The finned aluminum valve covers are left natural with

no paint or polishing. They do polish out nicely if you decide to go that route.

Or polish and paint.

Looks good with a polished intake, too.

[warren55]

I bought a plastic battery tray through Amazon and modified it (cut off one end) to fit in the available area. It's working just fine. Here's a thread I started with a picture here:

http://www.aoai.org/forums/index.php?showtopic=2556&hl=%2Bbattery+%2Btray

Edited December 5, 2014 by warren55

[Mike Hill]

Thanks for the replies and picture/photo links. I'll go the custom tray route and clamps following the repair to the fibreglass base area for the battery.

What decals were present in the engine bay?

FAN SHROUD - I've seen some with a large 'caution' sign on the fan shroud (I remember having one of those on my '64 Studebaker Wagon)

AIR CLEANER - Anything?

ANYWHERE ELSE

Thanks guys

Appreciate all the help

Cheers

Mike

[Gunslinger]

The warning sticker for the fan was for other Studebakers but wasn't put on Avantis...but I think it's a worthwhile addition even if not "correct".

The air cleaner probably had an Avanti decal that has a curved upper edge to fit. It also probably came with whatever GM information, tune and emissions decals pertinent to that year and model engine. Most of those are available from vendors like Studebaker International. Items like the GM info and emissions stickers can be found from Corvette and other GM reproduction suppliers.

Since all Avanti IIs were custom cars I wouldn't worry too much about what's correct...put on what you feel is necessary and suits you.

[plwindish]

The valve covers on the 400 motor of my 76 were orange like the rest of the motor with black pulleys and the black air cleaner. I wish it had come with the finned valve covers, but I think that was more of a 350 and 305 thing.

Decal-wise, the is a square warning decal on the driver side inner fender apron and a decal or two on the side of the GM air cleaner. I have the car in the paint shop right now, so I don't remember the wording on the decal that had a black background with yellow lettering. I've also sold the air cleaner so I'm not much help on that item either.

[Mike Hill]

Thanks guys.

Summer holidays are a distant memory so I can now head out to the garage. I have now reglassed and strengthened the battery tray area (made a new one) and adapted a metal tray with clamps to fit the space and accommodate the battery.

The next step in proceedings is to sort out the front springs. Is retensioning an option? I'm not knowledgeable on this. Replacement is an expensive option as they're no lightweights to ship from USA. Are there any other vehicle springs that wouuld replace them? What are the original specs?

Appreciate any help.

Cheers

Mike

[warren55]

I have heard that the Moog CC655 is a direct fit, and it's a variable rate spring. Fits the rear of a 1986-88 Buick LeSabre, among other GM cars.

[popeyesteve]

I am weighing the advantages of de-smogging my 1982 RQB3482 (stock 305/200R4, no inspection requirement in Oklahoma). The previous owner already got rid of the crossover, y-pipe and catalytic converter and installed true dual exhaust. Everything else is still installed, including the electronic Quadrajet, AIR system and computer controlled HEI distributor. I would like to do this in stages, starting with the AIR system to remove the cast iron exhaust manifolds with their air injection fittings to finish off the exhaust system. Has anyone used the Hedman Tight Tube Blockhugger headers (part number 69506) on your Avanti II? They look like a nice compact and efficient piece that would work well with a 305 and maybe later with a 350 or 383. But I would be reluctant to fork out the price of them just to be the first to try them if they would interfere with the steering column or something...and then have a dead car until finding and buying something else. The Sanderson units on "Gunslinger Bruce's" Avanti look pretty good, but these Hedman units look like they may take up even less room (making access to spark plugs, oil filter, starter, etc. a little easier?).

Steve