Good evening, I'm a newly minted gearhead and figured out later in life how much I love working and tinkering with older cars. So much so that I purchased a 1965 Mustang project to start once I've completed my 1975 Corvette project.

I've had numerous thoughts of what I wanted to do with the engine .... crate engine, stroker kit, etc. I've decided to simply keep my 350 small bock and rebuild it. As previously stated, I'm a new gearhead and don't really know what I want or need. I was hoping you guys could give me some good ideas. Here are some things I'm considering: 1) It's a driver, not a garage queen. 2) I want reliability of driving to the mountains, store, beach, wherever. 3) I also want performance because I like to have fun! However the primary mission will be cruising with the wife. 4) I would like to get more horsepower out of it and would like a Sniper EFI. 5) Rebuild my current automatic transmission or ??

Some additonal information: I do have someone very familiar with C3 Corvettes to assist in the rebuild. He has built dozens of engines. Yes, I could simply ask him then I would be stuck with whatever he decided. Collectively I would like some different ideas and takeaways. That's why I posed this to the group.

Thanks!

 

Edelbrock has top end kits that are very friendly to newer mechanics. The cam/heads/intake are already paired and they list how much power it makes. It also comes with the correct sized pushrods for the combo and good instructions.

everyone is different, but im not the biggest fan of EFI. It’s a lot of work(electric fuel pump, O2 sensor, routing everything so it looks nice) for not much gain(maybe 10hp?). I prefer a fine tuned carburetor.

Stock TH400’s are pretty stout. But if you go with a more radical cam then a higher stall torque converter will really improve drivability.
I’d recommend a higher stall converter regardless of what engine build you do, really improves off the line acceleration.

 

I'd go with retro roller cam, for EFI 112-114 LSA and no more than 225 duration. For pump gas 9.0 - 9.5 compression. There are lots of good head choices, AFR, Brodix, etc around 180-195 CC. As far as transmissions, the TH400 is a good transmission but I would consider converting to a 200r4 or 700r4 if it was me, that overdrive is nice for cruising. I went 700r4 and 3.70 gears, it makes a big difference.

 

If you go roller cam you’ll need a roller block. Then you’ll want some Vortec style heads. You’ll want pump gas so stay under 9:1 compression. Roller cams are more aggressive and are smooth as silk.
Flat tappet stock style motor is good, go flat top pistons. Vortec heads and a mild cam no bigger than .468 or so lift. If you are not afraid to learn I’d go with a fuel injection system of your choice. You will have a learning curve and parts may be mail order only when ever they wear out.
easiet would be ZZ4 or similar and carb it.

 

Thanks. Great advice. Definitely not afraid of learning something new. Been flying helicopters and private jets for years .. so I'm always learning! I'm kinda retired now so have a little more time on my hands.

 

Thanks. Great information. I was leaning towards the 700r4. I figured may as well upgrade the transmission if I'm going through all the trouble of rebuilding the engine.

 

I'm reading this thread. And all I've read so far is not great information.
no you do NOT need a different block to go roller cam. Lots of retro roller cam kits out there.
No, you should not think your compression should need to be that low on pump gas.
right around 10-1 to 10.5-1 has always been the magic number for a performance street engine on premium pump fuel. Wouldn't go past 10.5 -1 myself however.
with EFI and a good cam and ignition system you can easily double the H.P. of a 75 L48 with the right heads and flat top pistons. Your original block, just assuming you have a L48 Automatic. Will easily take 400 H.P.
Don't get hung up on the 4 bolt main block being the only go to. These old 2 bolt main blocks may not be the drag racers choice. But a 400 horse street engine with a automatic behind it it should be a happy combination for many years.
More information on what you actually have now would be helpful as you can see I have been making some assumptions here.
New block and crank for a fun weekend toy? Not really necessary. New pistons and heads, nice cam. Might be a more affordable option.
And compression makes power! 9-1 sounds a bit off if you want some cam.

 

Thanks for replying. I have an L48 with automatic transmission; however I believe the cam was previsously swapped. Not sure (yet) if anything else was replaced. I found an old pamplet in a stack of papers that came with the car for a performance cam. The engine also has a sticker indicating 225hp rather than the 165 I believed it came with. I would be extremely happy coaxing 400HP from this engine. Just looking for the right path to get there. After seeing your post I did some research and it seems 10.5-1 would be the max I could run. Assuming a decent cam was already installed... adding new pistons and heads would be an extremely affordable option to get extra HP.

 

Less than 9:1 C.R and Flat top pistons, is pretty much a smog 170 horse engine. No thanks.
Vortec heads limit your Intake choices due to different bolt pattern.

In most cases a safe threshold of under 11:1 CR will run on premium fuels w/o issues.

clcarell, go to YouTube and check out a tour of the Blueprint Engines Facility. Fascinating and educational video of what is available.
Perhaps a 355 C.I. around 400 horse will suit our needs. Every one of the engines is put on a dyno with print-out of horse.
Maybe they would be willing to sell and shp you one w/o an Intake & carb due to C3 hood clearance issues. I am sure they have heard of this challenge before.

 

Hey OP - Just food for thought, as they say....

I have a '69 vert, and I was originally planning to build out a 383 with a spare block I had laying around. So after taking it to the machine shop, and purchasing the Eagle stroker rotating assembly (using cast crank and hypereutectic pistons), Scorpion roller lifters, flat tappet cam (280H), pushrods, intake, heads, carb, etc etc, I was into the motor over $4K, and still had to assemble, which is no problem, and I intend to build that motor some day. But I decided to return all that stuff and go for a Blueprint Engines 396 'base' dressed long block, as I wanted to focus on other aspects of the restoration of my '69 - I've got an aggressive timeframe to get this Vette back on the road.

That motor is dynoed at over 500 HP/TQ, and cost me just over $7K all in, but it's got a forged rotating assembly installed in a new cast iron block made in the USA. That may seem like a lot, but I don't think I could not have built a motor for that myself., and it's got a warranty Some may argue that you don't really need forged rotating assemble, but to me, that was just the cherry on top. Original numbers-matching engine going into a crate to be stored away for prosperity.

BPE also offers a 383 that uses a seasoned block, cast crank, and hyper pistons for a much lower price point as well, but last time I checked they were sold out on that one. They also have a 383 long block using a new block casting, and it's at a pretty good price point too. I don't work for BPE or advertise on their behalf, but for me, going this route made better sense. Doesn't mean that would work for you, but I thought I would throw in my .02.

Gorgeous C3, BTW. Have fun with the project!

 

Thanks for the reply. I've been back-and-forth whether to keep a number's matching engine in it ... or install a Blue Crate. That's been my dilema. I've looked at the Blue Crate options and know they will give me the reliability and performance I want. Just kills me to remove the original engine. I think I can get over it (lol) but it pains me. The prices of these engines don't scare me ... I own a Cessna 414 and installed two new engines a couple years ago. So I've been desensitized a little.

 

Yeah, I understand. I thought about that too before I removed the original motor from my '69, but my justification was that I'd rather have something go wrong on a new non-original motor than to have my original numbers matching motor have some catastrophic failure that could potentially render the block useless. A rare occurrence, but something I considered.

Plus, we're talking 500+ HP - I wouldn't want to do those kind of upgrades to the original motor. I won't be winning any NCRS events with the crate motor in there (I'm also changing the exterior color), but that's not my priority anyway.

 

You wanted ideas that you hadn't thought of:

LS swap with a manual conversion.

For the price of a Sniper EFI, you can find a running 5.3 L from a truck. Much of the rest you'd have to do anyway (or want to ), like a new exhaust, and a fuel pump solution to support EFI. Then you can rebuild the stock engine at your leisure, for fun, or just leave it in the corner of your garage.

As for the manual, I own one of each, and can say with a straight face that my 4-speed car is about a million times more fun than the automatic. Which is why the auto is getting swapped.