OK - I am hoping I can get some help today - taking the 6 hours time difference into account - before I order the wrong parts this afternoon !!

Had a look at the new C3 and thre is good and bad.

1. Chassis is rust free - but cracked around the coil spring holder on the drivers side, and the bottom wishbone mount on the other side - no hassle here - just a welding job I think.

2. Steering and suspension rubbers / mounts are all shot - new ones should cure it all.

3. Now the problems.........

4. How do I tell a 48 from an 82 ??

5. It has a new Holley - the only markings I can see are P80 - what is this ???

6. Manifold is an Edelbrock torker - is this good or bad for this engine ??

7. Headers turn out to be "shorties" finish at the first flange - so the thermocouple and flapper valve are still there.

8. These shorties are connected through 2 1/2 pipes to the centre box - 2-1-2 style .
So is that centre box a cat ????

9. There is an elecrtic fan between the rad and factory metal fan - is that an extra or factory - cos if its an extra - its very well done. ??
An thinking of twin electric fans anyway.

10. Looks like the heads and lower half are untouched - bolts still oil encrusted etc, so possibly no cam change.

Anyone tell me of a good cam taking the holley and torker into account ??

11. Any thoughts or anyone done the L98 ally heads change - how good an upgrade is it ??

Need all help today , asap .
Thanks to all.
Hugo.

 

I'm not sure, but I don't think Corvette were produced in '48. I'll take it you mean '78. This site might help you diferentiate between the '78's and '82's. Idaho Page

I'm not sure but I don't think I'd weld the lower control arm....get new one's. At least that's what I would do.

What size engine do you have? 350? 427-424-502??


An electric fan was not factory on any C3. Normally when an electric fan is installed the engine fan is removed.

 

I think he means L-48 or L-82.

 

 

Hi, Yeah, I think he means L-48 or L-82 and not to start anything,,,,,,,,,,,,but electric fans were factory, my late great '80 ( L-82) has one! Peace,,,,,,,,,,,,,,,Craig

 

Correct.
SEE http://forums.corvetteforum.com/showthread.php?t=898700
Evidently he has a 78 350 auto- EDIT now it's 81 350 auto.

6 That's a single plane intake for 2500 rpm+. Since you want more low rpm power & more gas mileage, then you probably want to change to dual plane intake like Edelbrock Performer 2101 or EPS.

7 & 8 Exhaust- SEE what many refer to as my Exhaust topic.
http://www.corvettefaq.com/c3/ganeyexhaust.htm

9 The el. fan was factory on some later A/C cars. No need for more.

11 Sounds fine for you.

10 Not necessarily, intake needs to be pulled for cam, not heads.
Evidently you need to do intake first as this could fix you up, then report back. Cam- sounds like you would like HE 260H or XE256.

 

Well - just got the vin sorted out and it now seems that the car is actually a 1981 and is actually 322 from the last C3 made !!!!!!!!!!!- hence the electric seat etc.
Still need to know more before the end of the day - can anyone give me the phone number of a specialised 350 engine builder so I can chat over my problems ??
Cheers,
Hugo

 

I think he means L48 or L82. The easiset tipoffs are the L82 has a dual snorkel air cleaner, an aluminum manifold, and black ribbed valve covers. The L82 alos has a 2.5" exhaust vs. 2.25", though that me be hard to notice. The L82 typically also sports hood emblems denoting it. The L82 will also have an A.I.R pump, whihc usually gets removed, whereas the L48, unless a CA model did not have an A.I.R pump.

 

Not true. 1980 L-82 Corvettes had an electric auxiliary fan in addition to the steel one. Possibly the same for 81 and 82.

 

Not trying to burst your bubble, but they made C3's in '82 also. So if by your cars sequence number it is 322 from the endof a run, it is most likely the end of the '81 model year run.



All cars should have had the A.I.R. system regardless of which engine was installed. And in 1980 California cars did not recieve either the L-82 or the L-48. Instead they recieved the LG4 305 CI engine sporting only Auto's.

 

I hate to disagree on the A.I.R, but I did some extensive research on this as my '78 is all orignal but curiously had no A.I.R and none of the fittings for it. Strangely all of the component numbers matched, so I either had a very rare car or a normal car. I set out to understnd this. Normal L48s did not have the A.I.R system. The L48 used the CCS sytems which is completly different. This has been confirmed in a number of places. Here is some text I saved regading this:

1966 CA-delivered Corvettes, except for the L-72, used the A.I.R. (RPO K-19) system

1967 CA-delivered Corvettes, used the A.I.R. (RPO K-19) system.

1968 & 1969, ALL Corvettes used the A.I.R. system regardless of engine, transmission, or where delivered.

1970, Chevrolet went to the CCS (Controlled Combustion System) for emissions control on most Corvettes, except the LT-1s.

1971, Corvettes continued to use CCS (except LT-1s and LS-6s).

1972, A.I.R. system returned for most Corvettes except engines except L48s with the "CKW" and "CKX" code.

1973 - 1975, all Corvettes used A.I.R, except for the 1974 L48 with automatic and Federal emissions which used CCS.

1976, all Corvettes returned to CCS, except California-certified cars which used A.I.R.

1977, all Corvettes used CCS, except California and "High Altitude" delivered cars which used A.I.R.

1978 & 1979 all Corvettes used CCS, except California cars, "high altitude" and all L-82s which used A.I.R. L-82s were not available in California or "high altitude" areas during these years.

1980 - 1987, all Corvettes used A.I.R.

1988 - on, A.I.R. was used on most, if not all Corvettes, although many C4s use an electric air pump.

 

Guys - 81s only had the L-81. L-48 vs L-82 is non-relevant.

Good details on AIR in the thread, gliot1 is spot on with the L-48 vs L-82 bit, although 79 L-48s had dual snorkel air intakes as well.

 

Fifth Digit Code: 8=350CI 195hp (L48), 4=350ci 225hp (L-82)

 

everything you said sounds like it adds up to an '81 L-81 car. listen to what ganey says, he is very knowledgable about these cars.
the manifold and carburator are obviously aftermarket. the fact that you have headers complete with the butterfly valve indicates that you either have the very crappy stock exhaust or a really well done aftermarket exaust. because you said it still does the 2-1-2, i'll assume it's the former.
if the exhaust is factory, you could not possibly have a worse combination for performance. the stock exhaust is beyond lousy and woefully incapable of flowing like what a holley and single plane mainfold would require.
one thing you need to tell us is about your distributor. take a look at it and tell us if there is a vacuum advance canister on it. it should be a kind of silver cone shaped thing mounted on the base of the distributor and pointing toward the A/C compressor (if you still have one). if you have an '81 with a holley but you don't have that type of distributor, your screwed.
what we need to give you the best is your VIN. you can leave out the last 4 or 5 numbers for your own privacy if you like. just put in 'xxxx' instead of the numbers.
also, there should be two codes stamped into the block pad on the right side of the engine just in front of the head. if it's that old and unmolested, you'll probably need to dump a bunch of degreaser and scrub it with a brush to see it. one code will have the same last few numbers as your VIN. if it doesn't, it's not the original engine.
finally, if you have a way to post a picture of the engine, that would really provide us with some clues.
i understand you want to get some power and all but the first things i would do, if i were you, would be identify what you actually have. if your not restricted by smog laws, take the factory exhaust down to the nearest body of water and make a new artifical reef. then, replace that single plane manifold with a good dual plane and you'll be well on your way to having good street power.

 

o.k. just read the thread Ganey linked to. now i'm really interested to see your VIN.
electric fans are definately a plus (sorry Ganey). the reduction of rotational mass and parasitic loss is well worth the money. almost like a free 10hp. but please, do NOT buy engine parts from ecklers/MAM/etc, etc. go to jegs or summit. you'll save yourself half the pricing.
again, sorry Ganey, but there was definately something wrong with some of the engines between '72 and '90. more specifically, the cams used by GM in the late '70s through the early '80s were notorious for wiping out lobes, and doing so in relatively short order. before my overhaul 2 or 3 years ago, most people were amazed i still had the factory cam in my car at 100k miles. when i did pull the cam at 140k miles, there were at least 4 lobes in various stages of disintegration.
lastly, maybe i missed another thread but how about some more details about what you know of this car. do i understand this right? the car came from japan and now resides in jolly ole england with you?

 

Thanks for the help everyone.
My eyes are square from reading things up on the net - and all seems to agree about the exhaust etc - luckily I can see the sea from my window - its about 600 feet away !! One reef coming up !!
Anyway - numbers....Vinis.

161AY876(G)XB5108677 - its either a 6 or a G,

Block stamps,

V0814ZDD, and
1B54-(1) (7) -08677 - its either a badly done 4 or 1 or 7.

Vacuum advance is there and working well.

All emission stuff is gone - engine is as bare as a babies bum !!
Curiously, the choke plate is missing from the top of the Holley and it starts up and idles from cold too well - so indicating as rich as hell - the exhaust and the back of the car ( black soot ) confirm this - as did the phone call from visa to ask if my card had been stolen ( this is true ) cos I bought 3 tanks of gas in 5 hours to get home !!!!!!!

Now you know why I need the help - this Vette is increasing the UK's National Debt - in gas.

 

My 81 vin is this 1G1AY8768BSXXXXX (XXXXX being the sequence number) so in yours:
The second digid in yours is a G not 6 for GM
The ninth digit is probably a 6 not a G and I think that is just a random check digit
The eleventh digit is probably a S for St. Louis (assembly plant).

Or somewhere close to that. It looks like that is the original engine the ZDD it the 195 hp with the XXXXX matching on the block. Hope someone else chimes in that knows more about the vin, I'm not really sure but should be close.
Hope this helps.

YBnormal...drive a vette

 

Just been to the tyre shop - they gave me the choice of 255 -7-15, or 255-60-15.

Any comments or observations about which might be better..........?

Have noticed with the 255-70-15 BFG's on there at the moment - there is a little ( one eigth ) scuff line caused by the rear spring catching on occasions - but it may have been from turning while jacked up.
Out of interest - prices here seem reasonable - the 255-60-15 Avons are £64 fitted and balanced - about $112 ?? - seems OK.
C ya,
Hugo.
PS, Why have Ecklers dropped so much of the engine and mechanical stuff - not even a HD oil pump anymore ....!!

 

clutchdust

Thanks & you bring up a very good point to check dist.

Electric fans are fine. I don't type & was tring to keep it short. I fix things fast & it was more a matter of prioritys w/ all the issues here.
A few:
In a cold climate one might get by w/ just the factory el. fan, etc.
http://performanceunlimited.com/docu...ancompare.html

So the engine may be fine, cam not specified, would not expect a stock cam w/ a Torker intake. So just changing to a dual plane intake could solve a lot of issues he has w/ it.
Then he has to find out which carb he has, etc.-
hensen1954
do a topic on that.

Anyway the engines are fine. If a sto*k cam will get it home for a cam change that works for me.

 

You might want to check the nos. carefully- 225 70 15 & 255 60 15 were factory & correct dia. Many like the BFG & Dunlop.