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Hello everyone, I just joined the C3 community after getting my 1974 coupe. It needs some work, mainly to the body, but it runs pretty good! I plan on changing out most if not all of the fluids since the guy who had it before me couldn't tell me when they had been changed besides the oil (he only owned it for a year before he sold it to me). Would you guys have any other advice on things I should do or check on shortly after getting a new C3?
One other question I hope to get answered.. The previous owner said that the guy he bought the car from told him the engine was a rebuilt 400. I tried to have him elaborate on that but that's all he knew. I don't know much about engines myself so I was wondering if any of you could identify from the photos what kind of engine it is. I tend to think it's just the original 350 that's been rebuilt but I can't say for sure. There is part of an engine number under the timing belt on the right side but it's unreadable.
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
2022 C3 of the Year Finalist - Unmodified
2020 C3 of the Year Finalist - Unmodified
You're going to be getting a lot of great advice from guys sharper than me but I can tell you this much.
The 400 never came in any Corvette IF that's what it is.
Looks wise it's identical to a 350......
The numbers on the stamp pad look pretty faint so you may want to use some acetone or turpentine applied to a rag and rub lightly to reveal the numbers. Using something abrasive is not a good idea.
It’s only a matter of time until a helpful soul rips your heart out since you posted a picture of a C3 with (gasp) rubber fuel line in the engine compartment. That along with the timing belt comment can sometimes be a death sentence lol.
Someone here will know exactly what engine you have. To my eye it looks to have been made by General Motors and its orange.
Should I be concerned with the rubber fuel line? I don't know a lot about cars to include the C3 so any advice is appreciated. I can handle the criticism so that's not too much of a concern for me lol.
Thanks for the advice Jebby. The casting number for the block is 3951509. When I did a search for that it did come up as a 400 year 70-80 with two main bolts. Anyway to find any more information on it that you know of?
unfortunately you stamp pad has been partially removed by a prior decking. The last two digits are the "suffix" and used to determine what the engine was born as (SBC engines all interchange for the most part so just about any displacement and hp can be made)
Check the casting code on the back of the block near the bellhouse, on the drivers side. That will tell what bore it originally came with and further deduce what displacement might be in there
Last edited by Dynra Rockets; Aug 17, 2020 at 01:47 PM.
OP the consensus here is any rubber fuel line in the engine room is a recipe for fiery disaster. Yours looks pretty fresh/robust so I’m guessing that pretty 74 won’t self immolate anytime soon. Maybe put it on the medium priority honey dew list.
Oh and that piece of excrement that came after you with a knife while you were on the job got off light imo.
OP as you know, block rear casting number 3951509 is indeed a small block chevy 400 ci.
Also at rear block (But on passenger side) is a date code
Because of the narrow stamp pad, it's most likely from middle or later in 400 production cycle.
because your stamp pad's characters are all but obfuscated, my best hunch is it's Truck block.
Thanks for the advice Jebby. The casting number for the block is 3951509. When I did a search for that it did come up as a 400 year 70-80 with two main bolts. Anyway to find any more information on it that you know of?
Not really anymore info you need.....it has obviously been rebuilt.....so anymore info is irrelevant....
Now you know you have a 400.....they are great engine....I have one in my own....
Engine Identification
