its engine selection time

[Guyz55]

Ok so I have upgraded my entire brake system on my 55 3100 ....its time ti select a motor ...I am trying to decide on 1 of 3 ...one is a GM 350 that makes 290 HP and it is just about turn key with EFI and an HEI distributor ...Price 3700$$...2nd consideration ...a blue print long block ...base price 2700$ efi $795 , intake 180$, hei distributor,90$ and harmonic balancer 55$....3rd consideration is an ATK 2800$ ....with everything ( intake, harmonic balancer and water pump) except EFI which is $795 .

All 3 are 350's ....1 is brand new ..the GM 350/290 HP ....the atk and the Blueprint are remanufactured.....I was told by summit that both the ATK and the Blueprint are great motors with great warrantys ...the atk makes 325 hp and the blueprint makes 310 ....these 2 are the ones I am considering most strongly because they have the HP im looking for .....

so I am looking for insights, advice, input , any information that would aid in my search for a 350 that makes between 300 and 350Hp....and if you have any knowledge of the motors I have listed ,please let me know what you think ....

[mongocanfly]

I'd probably lean towards atk 1st and then the crate..

[Guyz55]

Originally Posted by mongocanfly

I'd probably lean towards atk 1st and then the crate..

any reason why

[mongocanfly]

Atk is well known and from what I gather reputable...turn key crate is hard to beat as well

[1project2many]

The GM 290/350 really isn't a great truck engine. The torque curve actually drops at cruise rpm and it's very noticeable. The engine begins to pull as rpm passes 3000 but in reality it always seems to feel like it's lacking when you're on the highway.




The ATK engine looks like it will have a much stronger torque curve and will feel better on the highway. It uses old style heads with 12 bolt intake and side bolt valve covers which looks like a classic SBC.



The blue print engine is an interesting combination. It appears to use small port GM heads from the early '90s with large valves. I'd be interested to see what kind of flow change those valves made. It's another flat tappet engine with a 12 bolt valve cover.


Is there a reason you're looking at flat tappet cam engines with older design heads? Hydraulic roller cams can make more power with the same lift and duration and they are more likely to survive as engine oil continues to get cleaner. There is a 350 hp ATK engine with a roller cam and L31 heads that has the potential to make power should you choose to change. Granted it's only a longblock but Summit's only looking for $2600 which means you can complete it for less than the 290 hp GM engine.

[Dan in Pasadena]

Guy,
Ok, let me ask since someone will:

Any reason why you're not considering an LS? You should be able to get into a nice 5.3 or 6.0 which will make more power, better mpg AND be more reliable than a carbureted engine. Just asking, no criticism intended.

[mongocanfly]

I thought the same thing dan..

[dsraven]

yup, me too. ls engine. easy start, runs smooth, reliable at any altitude, economical on fuel, ecm runs rad fans, trans shift points, electric speedo's etc right out of the chute. adapter mounts all over the web to convert from a small block if you have those mounts already. should be able to find an oil pan, exhaust manifolds etc that will work with just about anything. they are like the new small block was to the market way back when. lots of r&d going into that right now compared to the sbc. sorta like when the sbc came on the scene.
not saying don't do what you planned to do before. it is your project not mine. just saying that is what I would do. i am using the 4.2 inline 6 for my project but it was also set up by myself for an ls engine before that came about. I just wanted to be different and I got the donor cheap cheap.
if you plan on going ls, buy an insurance write off from copart or whatever. get a running driving unit with the engine trans combo you want. use what you need, sell the rest.
check out pirate 4x4 article on the whole ls lineage and differences over years of manufacture.

[bobinbc]

The OP asked about 350 sbc crate engines so I would look at this one if you're looking for HP vs $ Blueprint 373hp 350 https://www.summitracing.com/int/par...make/chevrolet Adapters are available to put perimeter bolt valve covers on these heads and you get a hydraulic roller cam
Hard to know for sure without knowing the rest of your combo: rearend gears, torque converter, transmission, intended usage, exhaust, etc.
I have a 383 sbc in my off-topic driver with a small cam and it makes tons of torque and only maybe 370 HP but it's a blast to drive on the street. For a street car that cruises on the highway in overdive, forget peak HP numbers, look for the fattest TQ curve from1800-2000 rpm on up.

[Guyz55]

All thank you

I am just a bit leary about the reviews ive seen on blueprint and atk ...yes they come with warrantys but who wants to deal with that ..

My thread should have been ...where should I buy an engine ...or who is the most reputable engine dealer ....I would definitely consider an Ls style motor however as you all know it all boils down to $$$$$$...im looking to do motor and trans ( 700r4) for around 5K....can that be done using an ls engine ????

[yossarian19]

5K for an LS swap is easy, though you aren't going to buy a fully dressed crate motor at that price.
You'd be buying an under 100K mile engine & transmission with all the accessories, a new wiring harness & whatever else you needed for your install.
I bet you come in well under 5K, and under 100,000 miles is still "new" for an LS motor, but I understand some folks want to open the crate themselves.

I put one in my '57 and while I've had complaints about my install (hey, gotta learn somehow) I love the engine. Had zero issues with it or with the EFI, plenty of power for an I-beam front end & it starts and runs perfectly every time. 4.8 liter LS.

[dsraven]

if you wanna go ls look around for a complete running wreck. that way you get everything you need. sell the leftovers. you may have to change the oil pan for road clearance if you buy a truck engine (cheaper usually) or some exhaust manifolds to fit between the frame rails but, unless you have an existing engine set up in the frame that you want to keep, it would work out to be money spent to buy the right stuff either way-sbc or ls. a few years back the ls stuff was a little more but now there are so many guys doing it, and so many vehicles with ls engine, there are more choices for used parts or specialty items at better pricing. a friend of mine would go to insurance auctions etc and buy a wreck. pull the driveline and sell it for swaps complete with the ecm. then sell what he could in the first week or 2 and the left overs went for scrap.he quit because there wasn't enough margin in it anymore. stuff got to be too cheap in the ls swap market.
just some thoughts. if you are gonna do a swap you must have some skills so why not try the "buy a wreck" idea and see where it takes you. worst case you sell it for a slight profit or take a minimal loss but learned a lot on the process. you could do the same for the sbc chevy if you wanted to go that route. unless you want a brand new engine with a brand new engine price tag.
up to you, it's your truck. they make injection for a sbc chevy too. I definately advise efi if you are driving it all the time.

[dsraven]

if buying a ls wreck look around for a camaro, they have oil pans and exhaust that will fit for ground clearance and between the rails. also a lower intake manifold. a complete car would yield an engine/trans/ecm/wiring harness/fuel system combo that works together, diff with disc brakes, master cyl to match brakes, steering column/pedals etc etc. dunno where your build process is at but just a thought. same goes for the sbc theory. sell the rest.

[dsraven]

hey guyz, post a couple pics so we can see where you are with your build. it is hard to connect the dots from thread to thread. howe far along are you and what have you got done? what direction are you going with it, daily driver, trailer queen, somewhere in between?

[_Ogre]

you can't beat a gm performance crate motor and definitely go with efi

[my56chevytruck]

I'm a BBC person so my engine preference is obvious, BUT, has there been any thought to the tranny or rear end gearing? I know plenty of SBC crate engine people that are running just fine in part to the gearing in the differential. So if a SBC is your choice keep in mind the tranny and differential you are using. Torq is necessary obviously, what's your driving plans??

[bobinbc]

Have you talked to any local engine builders? There should be a shop close to you that does reputable work, that way you could get an engine built to exactly suit your particular combo and driving style. Also they would be close if you had any problems or questions. I would go that way before ordering a "crate" engine.

Sorry to not give a clear choice among the ones you asked about but they simply don't give enough detail about those engines to make an informed choice.

Also the ls guys seem to be comparing apples to oranges, new sbc engine to used, salvage yard ls engine. There is no doubt that a ls will cost a lot more if you want a new or rebuilt one once you add in all the essential items you need to make it run, special gas tank, special headers, fuel pump and plumbing, computer, wiring harness, air intake plumbing, engine mounts, new sensors, different radiator, special brackets and pulleys to make it fit your chassis, Camaro or custom oil pan, etc.

They are a great engine for sure. Junkyard ls engine and trans for $5000 could be done I'm sure but not new...

[1project2many]

There is no doubt that a ls will cost a lot more if you want a new or rebuilt one once you add in all the essential items you need to make it run

Our experience is that the later generation of engine is substantially more expensive. We replaced the 6 liter in our shop truck two winters ago at 160k miles because a lifter failed. LS lifter failure is not uncommon. Resulting damage included destroyed cam, bent valve and pushrod, and ruined block. Cost for the new-from-GM longblock was $3286 from the dealer. By the time we installed it we were at $4576 for parts. We used a minimum of "extra" parts.

We also had a six liter fail in one of our buses at 138k miles because a lifter failed. Took out the cam, a pushrod, a valve, and the block. Total cost for longblock and parts was $4590.

[dsraven]

some of the ls engines have a fuel saving mode that cuts out cylinders by engine load required. there is a screen in the oil fitting under the pressure sensor. it gets plugged. easy to replace, just remove the sensor and pick the screen out. replace and so on. this canm have a bearing on the amount of oil getting to the lifters I believe. maybe an issue but fixable.

[OutlawDrifter]

Before selecting a platform. You need to decide what you want/expect from an engine. Do you want something with good street manners that can drive across the country reliably? Or do you want something that is a bit more wild, lopes hard, and is not very streetable?

A common tendency is to over-cam an engine for that "sound". Then after a month of poor street manners, you end up with something you don't care to drive...but it sounds cool!

I have built both LS and Gen 1 SBC engines. Here is my take. If you're looking for a low-buck, great driving street bruiser. The Gen 1 would be my pick, here is why. Torque is what moves you, and a Gen 1, pound for pound, will generally make more low end torque. Now, it comes with some drawbacks. It won't be as fuel efficient (depending on how you deliver fuel/air), and it will probably leak at some point (just the nature of the beast).

LS engines are efficient, seal up well, and unless you are buying salvage or used, still come with a bigger sticker price. When I built the engine in my Z28, I used a 55k mile LQ9 long block. It now makes 425hp to the rear wheels. It's not fun to drive in stop and go traffic though, it doesn't get hot, but it has too much clutch, and it's low speed manners are not desirable. Take it out on the road and tach it out to 7k and grab another gear and it just pulls like a freight train.

Don't get me wrong. I like both platforms. I have an LQ4 6.0L/4L80E combo sitting on the shop floor to go in my '49 GMC right now...but I'm still considering building a Gen 1 with some kind of multiport injection instead.

From the pricing you have above, it looks like you're considering the FiTech setup for fuel injection. I've heard a lot of good things. You can buy a 4-bolt main L31 Vortec 350, new, for less than $2200 shipped. Put the RamJet/HT383/395 marine cam in it, your FiTech setup, and you'll have all the power you ever wanted. If you go with a Gen 1, do yourself a favor and stick with a roller cam.

Or, find a 5.3l takeout with decent mileage, new oil pump, timing chain, and a BTR Stage 1 or 2 truck cam, and you've got yourself a runner.

SBC Gen 1 is great for low end and mid range power (unless purposely built for the high rpm stuff, not difficult either). LS platform is designed by the factory to have the power curves higher in the rev range. The L96 6.0L in my 2500HD likes to pull hills at 4k when loaded, doesn't hurt it one bit.

Lots of rambling in my post...clear as mud?

[whitedog76]

Why not just go with a Goodwrench 350? For $1600 you can have an ALL NEW longblock. For under $2000 you can have a nicely equipped one. Not to mention lots of money left over.

If you find that you want a little more power, you can swap in a larger bumpstick. If that's not enough, get some Aluminum heads. You would probably still be money ahead over the Bue Print or other crate motors.

[Guyz55]

OK so you guys are all great ...extremely knowledgeable and as always all of your input is greatly appreciated . what I am finding is it extremely difficult to pull the trigger on the following expenditures ..Motor ...at this point undecided ????L31 or 350SBC.....Tranny 700r4.....Fuel delivery ...Holley sniper efi ( definitely) , rear end ???? don't know ....how do I find out what the gear ratio is in the current rear end? and what would be optimal ratios ....3:56.....or 3;73's how do I find out if its posi or not ???? I am sure you were all in this position at one time or another in your builds .....I want my truck to be as best as possible and your all input will help get me there and is appreciated ....thank you

[mongocanfly]

The easiest way to determine what you have in the rear would be to pull the cover off and take a look..easy enough to see if its posi or not and you can count r&p teeth ...the other way to know ..jack up one rear wheel , put truck in neutral and see I you can turn driveshaft..if it spins then you don't have posi..a posi should lock in this situation..if it spins you can count the rotations of the driveshaft and the wheel to check ratio..just say one rotation of wheel results in 3 3/4 turns of the driveshaft would be around 3.73.....3 1/2 turns would be close to 3.56..and so forth
If your lucky you might find a tag or number on rear..

[Desert1957]

Originally Posted by Guyz55

Ok so I have upgraded my entire brake system on my 55 3100 ....its time ti select a motor ...I am trying to decide on 1 of 3 ...one is a GM 350 that makes 290 HP and it is just about turn key with EFI and an HEI distributor ...Price 3700$$...2nd consideration ...a blue print long block ...base price 2700$ efi $795 , intake 180$, hei distributor,90$ and harmonic balancer 55$....3rd consideration is an ATK 2800$ ....with everything ( intake, harmonic balancer and water pump) except EFI which is $795 .

All 3 are 350's ....1 is brand new ..the GM 350/290 HP ....the atk and the Blueprint are remanufactured.....I was told by summit that both the ATK and the Blueprint are great motors with great warrantys ...the atk makes 325 hp and the blueprint makes 310 ....these 2 are the ones I am considering most strongly because they have the HP im looking for .....

so I am looking for insights, advice, input , any information that would aid in my search for a 350 that makes between 300 and 350Hp....and if you have any knowledge of the motors I have listed ,please let me know what you think ....

I've personally had two of the GM 290 horse crate engines, Both were easy to install. Started right up, ran smooth , had good power.

Its hard to beet the price too. I waited for a sale on JEGS, plus a "Black Friday" discount. Had them shipped to my work address (free to Commercial address)

I would have NO problem going this route on a build.

[solidaxel]

Originally Posted by Desert1957

I've personally had to of the GM 290 horse crate engines, Both were easy to install. Started right up, ran smooth , had good power.

Its hard to beet the price too. I waited for a sale on JEGS, plus a "Black Friday" discount. Had them shipped to my work address (free to Commercial address)

I would have NO problem going this route on a build.

Excellent choice!!