Hey guys, just need some input. My grandpa has a 77 with an l48. Just wondering which you guys would think is more cost-efficient and will provide more power reliably, an edelbrock top end kit or a chevy crate 350. The top end kits are about half the price, but I'm not sure I want to take a risk whereas a crate motor is pretty much good out of the box

 

Yep just pick the power level and cost you can afford and go GM crate engine safest bet. Step up to one with a minimum hydraulic roller cam.

 

https://www.ebay.com/itm/GM-OEM-NEW-...kAAOSw1UdcvxpQ

 

I dont trust anyone to do anything right now a days. The generation that is coming up cant wipe their own *** with out screwing that up cause they could care less so I build my own engines and do all the maintenance myself. I'm still learning front end alignments cause the jerks cant find a 68 corvette in their preprogrammed computers

. If you dont have the time or "want" to do it your self, then get the crate from a reputable source like summit and make sure it has a warranty of some sort. I would go with a roller cam as well if its in your price range. Its well worth the cost upgrade. You can use any of the " off the shelf " oils with those unlike the flat tappet cams. Saying that I still have a solid mechanical flat tappet in my motor but I use a mobil1 oil designed for the flat tappets

 

Agreed - crate if you're considering it. If you install a top end kit you may ultimately end up facing a rebuild, depending on age, mileage and condition of the rings, etc. so the investment may end up just as major.

 

Joe said it - "Crate if you are considering it". Jackson linked it. You can't build one as powerful and reliable yourself for less. You actually need some other reason do do it any differently.

 

I have to agree with those guys.
Thats not exactly a performance package but it is a great price for a reliable engine. It cost over $4k in parts to build mine from the mains up. If they back up that warranty you really cant go wrong. If you want more than a couple hundred horse you should contact them and see if they offer up a motor with 10:1 pistons, aluminum heads, and a roller cam in the .470 lift range.

If you get that motor its a great place to start except for the lower compression pistons. you could get the compression up with a 58cc chamber or smaller aluminum head.

 

heres a 350 hp motor that would be fun from those guys
https://www.ebay.com/itm/OEM-NEW-GM-...cAAOSwyNtdARIh

Its still cheaper than my build. It would be agreat start and in the future you could just throw a bigger roller cam, good aluminum heads in it and a nice intake and bump up the HP with little effort. Again smaller chambers could get you to the 10:1 compression and still run good on pump gas, maybe higher octane but the aluminum head should negate that

heres all there motors

https://www.ebay.com/sch/m.html?_ssn...ngine&_sacat=0

 

Nice find Jackson!!

 

The Edelbrock kit won't work on the L48, because of the dished pistons. You'd have to go with heads that have a really small combustion chamber, like the L98 aluminum heads off've the early 4th Gen Corvettes ('87-91). I did this with my L48, but there's a lot to that swap, that you should look into. It is a bolt on, but you've got to make sure the heads are good, have no cracks and have a set of good valve springs installed.

 

I have no smoking gun, but ...

For a LONG time I've studied the above crate GM OEM NEW CRATE Engine 350 (Older GM pn 12530283) Chevrolet 5.7 L31R (Newest GM pn 12681431).
That crate is NOT marketed as hi-po or listed in Chevy Performance Parts (f.k.a. GMPP) catalogs ... because ...
... it's marketed as a replacement motor aka old GOODWRENCH ... and NO, it's Not a reman / rebuild ... it's ALL BRAND NEW.

Not certain why & No smoking gun, but it seems GM commands a premium price point for similar motors marketed as "PERFORMANCE" ...
... while similar NEW replacement aka GOODWRENCH motors sell for far less sans a "performance" label.

For many months, I've suggested above crate here on CF to those considering a crate. The above seller Radley is a bona fide GM dealership ...
... and its price for this crate are Hundreds $ LESS than summit, jegs, sd, speedway etc ...
... Look at Radley's deal ... price includes free ship & a spend-anywhere $100 Visa card ... and they accept offers.
... And, who knows? .... Maybe your local GM dealer might meet or beat Radley's deal?

In numerous threads I've suggested the L31 crate and told how a clever fellow who buys it and then spends less than another $1K ...
... can have a local machine shop finish the fuel pump pad, then easily DIY swap cam, springs & retainers ... add Vortec intake manifold ...
... and make a solid 375 - 400+ crank horsepower ... reliable & dependable. All New good horsepower for under $3K ... even less!

FWIW ... above L31 replacement crate motor is rated at 255 hp in a GM truck with restrictive OE Single Exhaust & with restrictive OE Catalytic Convertor.
I've suggested this motor (as is, no mods) will perform as well as, or perhaps outperform any OE L48 from the low-compression C3 era (1971-up).
Note: when compared with low-compression OE L48, above OE L31 has far superior heads, larger steel roller cam profile and more compression.

 

Solid options others have listed above, but one option is to check around your area for a local engine builder and price it out that way. Tell them what you want out of the motor and let them come up with a price. The only problem with crate motors is dealing with any warranty issues. If a problem occurs, you have to pull your motor and ship it back to them. If you have an issue with a local built motor, you can go right to the source. I had a 454 built locally and it has performed flawlessly, but I did have questions on setting up a few things and bent there ear for advice a couple of times. Was also nice to hear it run on the dyno. They also came in way under my budget that was looking at.
Good luck.

 

Warranty
GM crate motors
Any nearby GM dealership

 

That's a great lead! That L31 is also a roller lifter motor too, with the one piece rear seal crank. For $2K? That's a smoking deal!