AVANTI PRODUCTION NUMBERS

[Mike Hill]

Hi. Does anyone have accurate figures for the actual production numbers for the Avanti II RQA and RQB? Do the year production figures match with engine installations?

How many were produced with the 327? 350? 400?

327 supercharged - 2?

Manual trans cars? When did that option stop?

Just interested to know. No figures like that in any books I've read.

Cheers

Mike

[Gunslinger]

I don't believe that anyone knows for sure. Even sales records may not be accurate. Avanti Motors was known to skip serial numbers, title a car built in one year that was unsold as a different year when finally sold, even repaint a car a different color to sell it.

As far as factory supercharged 327 cars, we know for sure of one. Supposedly there were a red and white supercharged cars, but we also know the one we know of had been painted white at one time and repainted red, so is it being counted as two cars or simply one?

The use of the 350 engine began officially with the RQB series but that may not be absolute. It would take going through every production order and building a data base to answer many questions.

[mfg]

I believe that the 327 CI Chevy engines were phased out BEFORE RQB production began. As an example, the RQA Avanti ll which I owned several years ago came from the factory with a 350 CI Chevy engine. (RQA-0298)

[boogieman]

As much as we would all like to know these figures, the lack therein only adds to the mystery and mystique

of these cars. And the mystery only deepens with the passing of time. Special cars they are.

[plwindish]

It's my understanding that engine selection changed as the ever increasing pollution regulations changed.

65-68 - 327's

69-71 - 350's

72-76 - 400's- some early 400's were 2 bbl carbs and later ones were 4 bbl.

77-80 - 350's again

81 - on - 305's

Wasn't 74 the last year for 4 speeds?

305's on the Silver Anniversary models were also supercharged.

[Gunslinger]

From some documentation I have, the first 350 equipped Avanti II was RQA0315...a very late RQA model. The first 400 cubic inch engined Avanti was the first 1972 Avanti...RQB1801. That was with a 2-barrel carburetor. The first 400 cubic engine Avanti with a 4-barrel carb was RQB2050 (1974 model year). I have no information when Avanti Motors began installing the 305 but it was the 1978 model year or later.

[Guest dapy]

Couldn't the RQA, RQB and later cars be retrofitted with other compatible, available GM engines? The 1988 Anniversary model Sexton is selling lists a 350/385 GM supercharged engine. Presume that car is on a Monte Carlo chassis.

[Gunslinger]

Sure...a small block Chebbie is a small block Chebbie. You can swap any if you like. You can get 427 small blocks that use modern casting methods for the additional displacement. THAT would be an engine that could spin the car around the starter!

There's also been more than one LS-series engine installed in an Avanti engine bay. I considered doing that with my car but the cost-benefit wasn't there for me, though I still would have liked to.

[mfg]

From some documentation I have, the first 350 equipped Avanti II was RQA0315...a very late RQA model. The first 400 cubic inch engined Avanti was the first 1972 Avanti...RQB1801. That was with a 2-barrel carburetor. The first 400 cubic engine Avanti with a 4-barrel carb was RQB2050 (1974 model year). I have no information when Avanti Motors began installing the 305 but it was the 1978 model year or later.

Interesting mystery!....RQA 0298 was built in '69,...but not sold till '71. (and titled as a new '71!) (Original buyer cancelled order)

[Devildog]

Sure...a small block Chebbie is a small block Chebbie. You can swap any if you like. You can get 427 small blocks that use modern casting methods for the additional displacement. THAT would be an engine that could spin the car around the starter!

There's also been more than one LS-series engine installed in an Avanti engine bay. I considered doing that with my car but the cost-benefit wasn't there for me, though I still would have liked to.

You mentioned the L-S series and just to stimulate others thinking. I have been helping a friend install a LS-3 from a low mileage roll-over salvage Camero in his C-2 Corvette. We helped another friend find salvage LS for another project. After looking at several salvage option, we found the best option was a NEW engine package from GM.

It was $7500 for a NEW LS-3 with wiring harness, an 'open' computer module, and the electronic accelerator peddle. LS-3 is the aluminum block, so that is something consider if one is looking higher performance.

Joe

[drat]

My RQA0319 was one of the 1st 350s? Cool.

The engine code came back 1968 crate motor

[Gunslinger]

That the engine code comes back to 1968 shouldn't be a surprise. Avanti Motors purchased engines in bulk to get the best quantity discounts...simply a good business practice. It was something like a six month supply at a time. Since production was low, it would be very easy to see an engine purchased in 1968 not used until much later...into a different model year.

[plwindish]

The 400 2bbl engine is interesting in that the information I looked up for the GM 400's is that they had a higher nickel content block and also had 4 bolt mains while the quadrate 400's had a lower nickel content block and 2 bolt mains. If the earlier 400 was a stronger built motor, then why the 2 bbl instead of the quadrajet?

When I had the 400 in my 76 rebuilt, I wanted to keep it original so I had the motor redone and warmed up. From what I put into the whole process, I could have gone with an LS for not much more money.

Regarding trans swaps, the 200R4 required no drive shaft mods from the THM 400, just a rear trans mount.

[Gunslinger]

It may be different casting numbers for the difference in nickel content or even the differences between two different foundries in how they did things and still be within specs. Chevy used a common small block casting number for about ten years back then for most small blocks. The differences between number of main bearing bolts was how they were machined for the end use. Even in Corvettes they were mostly all the same casing number but machining after casting made the difference. It didn't matter whether it was intended for a base engine L48 or the optional L82...L48's were drilled for 2-bolt mains and L82's were drilled for 4-bolt mains. The castings were identical.

I'm thinking for 400 engines may have had different casting specs due to their not having cooling passages but steam vents due to the the very thin cylinder walls. Maybe the extra nickel was required for the desired longevity. Just a guess on my part. A small block Chevy expert can have more knowledge on that.

I'm very ambivalent on the 400 engine. Many engine builders think the right 400 block makes for a real torque-monster. Other engine builders won't touch them. Maybe it's like Studebaker with R3/R4 engine castings...good candidate blocks have to be specially selected from production runs to handle the buildup and torque.

[warren55]

Interesting info on the 400 motor. I had zero experience with a 400 before I got RQB1992. I had not heard a lot of good things about it, so I expected the worst after looking at the HP ratings and hearing of the overheating problems. I must say I've been pleasantly surprised by this motor. From what was posted above, it was apparently a 2bbl. motor when it left the factory, but someone has installed a standard GM 4bbl. manifold on it and it has a Holley Quadrajet replacement carburetor on it.

It has a surprising amount of power, and will easily set you back in the seat when you kick in the secondaries! I had figured I would drop a crate 350 in it at some point, but I'm in no hurry to do so!

I'm not out to race anybody, but I'm no stranger to quick cars. My other toy is an SL500.

[plwindish]

According to the engine builder that did my 400, its very easy to get HP and torque out of the motor. He asked what I wanted out of the motor and I said 325 - 350 HP and he replied, "That's all?"

After the tear down and cleaning, new pistons, a hydraulic roller cam, line boring the crank, block decking, and headwork to open up the air passages, a new aluminum intake and a Performer carb got dyno-ed at 365 HP and 460 lbs torque before going back in the car. The car can definitely put you back in the seat when putting your foot into it.

[mfg]

Interesting info on the 400 motor. I had zero experience with a 400 before I got RQB1992. I had not heard a lot of good things about it, so I expected the worst after looking at the HP ratings and hearing of the overheating problems. I must say I've been pleasantly surprised by this motor. From what was posted above, it was apparently a 2bbl. motor when it left the factory, but someone has installed a standard GM 4bbl. manifold on it and it has a Holley Quadrajet replacement carburetor on it.

It has a surprising amount of power, and will easily set you back in the seat when you kick in the secondaries! I had figured I would drop a crate 350 in it at some point, but I'm in no hurry to do so!

I'm not out to race anybody, but I'm no stranger to quick cars. My other toy is an SL500.

I agree with you on the 400's power. When my '73 Avanti was registered and running well I believe it would 'run away' from the average R2 Studebaker Avanti!

[Gunslinger]

That's easy to understand as over one hundred extra cubic inches makes for significantly more torque down low. In the mid- and upper-rpm ranges, the supercharger boost of the R2 would more than make up the difference in top end. I think the only question might be how long a lead did the Chebbie powered '73 have before all it saw was the R2's tail lights.

[plwindish]

1/8 mile, I'd think the 400 would take the R 2. 1/4 mile would give enough time for the top end supercharger boost to be kicking in, the R 2 would be coming into its best power range while the 400 would be on the down hill side of its power, as they aren't a good high rpm motor.

[Skip Lackie]

It's my understanding that engine selection changed as the ever increasing pollution regulations changed.

65-68 - 327's

69-71 - 350's

72-76 - 400's- some early 400's were 2 bbl carbs and later ones were 4 bbl.

77-80 - 350's again

81 - on - 305's

Wasn't 74 the last year for 4 speeds?

305's on the Silver Anniversary models were also supercharged.

In answer to the question, yes, the 1974 model year was the last for 4-speeds until the Blake years. My understanding is that effective for cars built on or after 1 January 1975, the EPA required the loan of one car with each available engine/trans combination for emissions testing. (Detroit model years may begin in the fall, but most emissions and safety regs become effective on January 1.) Avanti Motors didn't want to provide the EPA with more than one car, so they dropped the 4-speed from the catalog. They did build several 4-speed cars late in 1974, either for orders or stock. I own one of them, apparently the next-to-last built.