Another C3 Import Question!...
- Thread starter GCorvette
- Start date
Mr. Cricket
Committee Member
ZR1?
Emc
Supporting vendor
Yes the LS7 was a factory engine that could be purchased separately then installed by the dealer.Thank you, so is this correct as to what was available with an automatic box?
1971
350 - 270hp SB
454 - 360hp BB LS-5
454 - 425hp BB LS-6
1972
350 - 200hp SB
454 - 270hp BB LS-5
454 - 425hp BB LS-6
Chuffer
CCCUK Member
GC Corvette , Don`t forget what Roscobb said about pre 1972 cars being rated gross BHP and not net BHP . That is why early cars appear a lot more powerful . OK , later cars suffered from increasing smog emissions strangulation that knocked back BHP but it is the different methods of test bed measurements used that really makes the difference .
GCorvette
CCCUK Member
As I always declare and you can see, I'm not at all mechanically minded sadly. My brother builds race cars and engines so he got all those genes.
The next problem is sadly I can only drive an automatic now thanks to a dodgy surgeon.
After much deliberation, I have narrowed down my wish list to an original 71/72 or possibly a modified 73 C3.
Having only been able to drive mid 70's C3 previously, I have no grounds to say if I want a Big or Small Block from the earlier years.
What I do want though is something that will put the tail out on acceleration in an auto if I want to do that and that isn't hiding that rumble but I'm not looking for a modified 450+bhp output C3 either.
Having grown up around race cars, the gutteral rumble of a C3 with side pipes at Spa in the 70's is cut into my audio memory files.
My budget later in the year is £20-30k ideally, so I like to think I will end up with what I want which is a ready to go nice example (not a show car) the only other criteria is it must be a specific colour though.
I'm willing to wait for the right car to come to EMC or find one State side to import with help to check it over before purchase.
So do I go Big or Small Block in a 71 or 72 or modified 73?
What say you all?
Mr. Cricket
Committee Member
'71 SB 270 BHP and not much to go wrong. Has the super reliable Rochester Q-Jet carb. Stick some Glass Packs & Resonators on it so it sounds like a big block.
Letank
CCCUK Member
I am also on the lookout for a nice 69-72 myself. If I find one then I will be looking to sell my 73. It already has some tasteful modifications and would be a good base if you wanted to make further mods to unlock even more bhp. Alternatively it wouldn’t take much to return to standard either.As I always declare and you can see, I'm not at all mechanically minded sadly. My brother builds race cars and engines so he got all those genes.
The next problem is sadly I can only drive an automatic now thanks to a dodgy surgeon.
After much deliberation, I have narrowed down my wish list to an original 71/72 or possibly a modified 73 C3.
Having only been able to drive mid 70's C3 previously, I have no grounds to say if I want a Big or Small Block from the earlier years.
What I do want though is something that will put the tail out on acceleration in an auto if I want to do that and that isn't hiding that rumble but I'm not looking for a modified 450+bhp output C3 either.
Having grown up around race cars, the gutteral rumble of a C3 with side pipes at Spa in the 70's is cut into my audio memory files.
My budget later in the year is £20-30k ideally, so I like to think I will end up with what I want which is a ready to go nice example (not a show car) the only other criteria is it must be a specific colour though.
I'm willing to wait for the right car to come to EMC or find one State side to import with help to check it over before purchase.
So do I go Big or Small Block in a 71 or 72 or modified 73?
What say you all?
Roscobbc
Moderator
Handbrakes are only for pussy's with insufficient power to get the back around using the gas pedal only..........
Roscobbc
Moderator
Ironically in economy terms a big block powered car can be as good as (or 'bad' as) a hot small block powered car. Something that sticks in my mind is reading a mid 60's Hot Rod road test years ago on a manual C2 coupe with a factory rated 370hp 327 snall block (probably still got is somewhere). Bearing in mind the mpg figures were shown in USA gallons rather than Imperial youwould need to add a couple of mpg to the figures - which were...........11-12 mpg on average. So fairly close to a lower tune big block. The small block car would have a low ratio rearend to keep things spinning and prevent low-end bogging (not needed on big block). 50 odd years later much of the aftermarket tuning gear like stroker rotating assemblies, cylinder heads, cams and induction is far better optimised than in the past. Careful selection of components can give the best of both worlds (performance and relative economy) and run rings around all those 'early' HiPo engine options.
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CaptainK
CCCUK Member
I knew about the change from gross power to net power measurements, but I didn't realise that there was no change from a 1971 gross 330hp engine to 1972 255hp net engine. Seems like an awful lot of HP lost in those ancillaries etc.
I wonder what my 1968 "gross 300hp" engine would be in net? I know when I had it rolling roaded a while back it was doing 245hp.
Roscobbc
Moderator
Manuacturers quoted output figures were very speculative in the 60's - (no, read that in many cases as outright lies!) - who would buy a sports car like a Corvette if the manufacturer quoted a power figure of, say 170hp or 180 hp? - no one! - well, the realality was that people did buy them in the mid 70's! - Emission laws with low compressions, very soft camshafts, smog pumps and ultra lean carbs gave us HP figures that total many current family cars easily achieve with a third of the engine capacity. Didn't stop people buying Vettes did it? - the cross section of the buying public was different and like the of wearing of clothing like platform boots, flared trousers and brown and orange clothing 'performance' cars became unpopular.
CaptainK
CCCUK Member
Yeah, I read a lot about that - changing the quoted power output to fit the legislation at the time, and to help with insurance cover and other such things. The details elude me now, but there was the 430hp (?) quoted 427 engine that on paper looked less powerful than the "top" 435hp (?) quoted 427 engine, but in reality it made around 550hp or something? (Note: All from my poor memory, could be wrong, I want to say L88 as well).
I suspect my 300hp (gross quoted) 327 probably was a bit "off" that value originally, but for actual 245hp (net) rolling roaded a couple of years back, it seems fast enough ish for me (though granted I do have an inkling to put more power into it to at least get it over 300hp).