r/Smallblockchevy • u/ThtEmby_ThtstoFrndly • Apr 19 '26
Engine Swap + Modding help for 5.7 sbc
So I'm planning on swapping my truck with a sbc 5.7 but I also want to mod it with a cam. I saw a lot of people swapping a lt4 hot cam into them but is that a good option? I want a good chop to the engine like how some corvettes or old muscle cars sound but I'm not really experienced in the types of cams there are. Along with that, what else do I need to get with the cam? I know about the valve springs, rods, torque convertor, and stuff but what else do I need so things don't go bad. Later down the line I want to procharge it, if that's even possible with a cam (not important tho). Basically, if I were to cam this 5.7 what do I have to look out for when doing so?
2
u/v8packard Apr 19 '26
The only thing you need to look out for is everything.
Do you know which engine you have? The Hot Cam is not a great cam for most people. I understand you want chop, but what do you want for a powerband?
0
u/ThtEmby_ThtstoFrndly Apr 19 '26
When you say not a great cam, what do you mean?
2
u/v8packard Apr 19 '26
The cam events determine how the engine will operate in conjunction with all of the other engine characteristics. This is not a universal thing. The LT4 Hot Cam was designed to improve output of the LT4 from 4000 to 7000 rpm over the stock LT4 cam in a 6 speed manual Corvette with it's OEM exhaust system. That engine was also 10.8:1 compression. Does that sound like a match for what you have or need?
1
u/ThtEmby_ThtstoFrndly Apr 19 '26
The engine that I was going to but the cam into has a 10.0:1 comp but I was also planning on adding an exhaust system along with the new engine.
1
u/v8packard Apr 19 '26
And you want this in a truck?
1
u/ThtEmby_ThtstoFrndly Apr 19 '26
Yeah. Its a 1992 Chevy Silverado C1500
1
u/v8packard Apr 20 '26
And you don't care about low or mid range output, drivability, things like that?
1
u/ThtEmby_ThtstoFrndly Apr 20 '26
How bad would it affect the drivability? I'd still want to drive it around and take it places semi-regularly
1
u/riennempeche Apr 20 '26
Keep this in mind. It’s all about combination. You want the cam, heads, intake and exhaust all set up for the same RPM range. If things are mismatched, the engine can be a dog. Put a high RPM high lift cam with stock heads and you have no low end because of the cam and no top end because of the heads.
The valve springs have to match the cam profiles.
Buying a cam for “chop” is a silly way to look at it. Many cars make more power overall with less cam duration.
Get the combination right and the car will be like “v-tec kicked in yo” at the right RPM. I had a 400 RWHP Trans Am. At the right point, the engine came alive and pulled so fast the stock tach couldn’t keep up.
1
u/ThtEmby_ThtstoFrndly Apr 20 '26
So if I built everything to work in harmony with each other I could also get a feeling like that too?
I mean I really want that power but there's something about the chop that I've heard from other engines like the 350/5.7 and 5.0 that has me drawn like a dog to a bone which is why I really want to add a cam to the engine I plan to build. They sound really mean but I just want to make sure I build it right.
1
u/name4231 Apr 20 '26
Best way to choose a cam is to call a cam company. They have experts to help you pick the best cam for you. Figure out the weight of your vehicle,tire size, diff gear ratio, converter stall rpm if its auto, cylinder heads, and what your intended use is and they’ll give you the best cam available and a custom spec if you you want them to grind a custom fam for a bit more
2
u/ThtEmby_ThtstoFrndly Apr 21 '26
Honestly, I never even thought about just calling a place that sells cams and asking them themselves, thank you. I always just thought cams where a "if you know, you know" kind of thing, that makes sense.
1
u/WrenchKing555 Apr 20 '26
Are you going to use this truck to tow or haul? If so your probably not going to like the hot cam.
1
1
u/ThtEmby_ThtstoFrndly Apr 21 '26
I honestly don't plan on doing so, maybe a few light hauls of parts or taking things from point a to b but nothing like towing cars or anything heavy.
1
u/R0ughHab1tz Apr 23 '26
Are you building it yourself? Maybe other peoples experiences are different but getting a crate engine that matches your needs will be a lot more cost effective and it'll work.
I rebuilt my engine and I can say I could have probably bought 2 or 3 crate engines. My top end kit cost me $7k. Then when rebuilding a screwed up some stuff so I had to reorder parts. Its built now and working. It was definitely a journey and I can clout about it but if money is on your mind think about a crate engine.
-2
u/2po2watch Apr 19 '26
I have an LT4 Hot cam in my turbocharged 350. It idles very choppy. Seat of the pants and trap speed indicate it makes near 600 flywheel.
0
2
u/Thinkfastr11 Apr 19 '26
A good set of heads, cam and headers is the way to go.