Jegs Crate or LS engine swap.

[Vegetta]

Im about to sink $7500 into my 71 Blazer engine. Should I go with a Jeg's Crate turn key or do an LS swap. Anybody with the ins and outs of both would be very helpful. I'm leaning towards the 454 Jegs motor simple because its plug and play. Thanks Mickey

[LockDoc]

Originally Posted by Vegetta

Im about to sink $7500 into my 71 Blazer engine. Should I go with a Jeg's Crate turn key or do an LS swap. Anybody with the ins and outs of both would be very helpful. I'm leaning towards the 454 Jegs motor simple because its plug and play. Thanks Mickey

I have installed both. They both have their pros and cons. The crate engines have the straight forward installation and old school charm, while the LS engines have the ease of starting, minimum maintenance requirements, and high mileage possibilities.

The cons for the LS engines are wiring requirements, speedometer conversion problems, fuel delivery requirements, and on the road repairs.

Cons for the crate engines are continued maintenance (somewhat dependent on what distributor is used) harder starting, generally less fuel mileage, and initial break in requirements.(depending on valve train)

On the road repairs used to be a plus for the crate style engines but anymore none of the auto parts stores keep repair parts on hand, everything has to be ordered. So that advantage has kind of gone down the drain.

I really like the 350 crate and NV4500 combo I installed in my '72 Dually. It gets decent gas mileage, will cruise down the interstate at 75 or 80, and pulls my 20' trailer like a champ. I also like the LS1/4l60e setup I installed in the '67 Panel Truck. It will cruise at any speed you want to cruise at, gets 24 mpg, you can stand outside the truck and start it in any weather, and it runs as smooth as glass....

Conclusion is it kind of depends on what you will use the truck for.

This is just my opinion and will differ greatly from person to person.

LockDoc

[JLubben]

LockDoc, What did you use for FI and trans control on the LS1 swap? I'm curious.

[MoFormula]

I took the crate path in SBC 350. Only thing I would do different is to go EFI instead of carburetor. I think that is a great blend of both worlds.

[Vegetta]

Originally Posted by MoFormula

I took the crate path in SBC 350. Only thing I would do different is to go EFI instead of carburetor. I think that is a great blend of both worlds.

Why EFI and not Carb? Thanks

[GR8-68]

Exactly what I am doing, a sbc 350 with the Holley sniper efi system

[jessemthompson]

The answers you'll get in here will vary with opinion,I went the LS route. I drive my truck every day so I wanted easy starting, good dependability, good mileage and low maintenance. The LS provides that. To top it off it has great power too. The wiring is not difficult. There are companies who sell wiring harnesses or you can have the factory harness modified.

[MoFormula]

Originally Posted by Vegetta

Why EFI and not Carb? Thanks

Easier starting, better performance, better gas mileage.

[LockDoc]

Originally Posted by JLubben

LockDoc, What did you use for FI and trans control on the LS1 swap? I'm curious.

The LS1/4l60e is out of a '99 Camaro with stock injection and it has a 2001 wire loom and ECM/PCM. All functions of the engine and trans are controlled by the computer. It also controls the electric fans and cruise control. The A/C will be stand alone. There is a great forum on here for the LS swaps:

http://67-72chevytrucks.com/vboard/f...prune=-1&f=206

Check it out.....

LockDoc

[weq92f]

I am biased.

You can turn that Jegs 454 into something that approximates the positives listed for the LS swap. That is, with FI.

Go the old school crate BBC and match it with a bolt on FI system ( Not a salvage yard Hodge podge but a bolt on carberator replacement FI system ).

This way you can have both old school "charm" and ease of operation due to having an ECU control the FI. Back that up with some modern 4LXX tranny or manual and you've got a great drive train that will be very reliable and easy to operate!

-klb

[leftybass209]

I like both, but here's the real world breakdown:

The cost of the LS exceeds the sbc. Headers, radiator, wiring, gauges, transmission, fuel tank, etc. It adds up. A stock LS gets (I'll average) 7-8mpg more than a mild sbc. So in gas, it'd take you possibly years just to break even on the cost of the swap depending on how much you drive it. If you go used, an LS will average 325-350k before things start needing replaced or rebuilt, and your engine may already have 90-150k on it. Sure, some can go 450-500 but that's more luck and not an expected average, as a sbc can go 250k+.... obviously not expected. The more HP/TQ either engine is built for, the less longevity it'll get if you're using that power.

EFI is great on a sbc too, but again, cost vs. Return. You aren't squeezing an extra 5mpg out of EFI over a well tuned carb. At over 1200 bucks on the cheap side, that's a big investment if the expectation is mpg. They will obviously start easier than a carb year-around, but a well tuned carb'd sbc only driven in warm weather doesn't and shouldn't have starting issues to begin with.

Again, no negatives or bias towards either. The only time an LS swap makes sense for those who are budgeted is if you don't have ANY engine parts already.

[TXBoudy]

Trick question! I simply can't imagine either choice will make you sad. I wanted an LS truck but my donor had a pretty decent 400 so I'm staying with it but adding the Holley Sniper EFI.

[davepl]

I put an LS3 eRod 430hp in my '69 Camaro. Didn't even option up to the 480hp. Costs more and is more work than a classic smallblock swap, but in the end, totally worth it.

With that engine, a TKO-600, and a Currie 9-inch helical locker, it cranks, starts, idles and drives like a new 2010 Corvette... at least as far as the engine and drivetrain is concerned.

If originality is not a primary concern, I'm now a strong advocate for the LS engine.

[bs46488]

I have 2 projects... My C10 with a mild built 454 and a Nova with an LS swap. If I only had to choose one.....I'd go with the 454.

With the budget and choices you mentioned, I would go with the crate engine and an EFI system (like Fitech or Holley Terminator, etc)

[Z10]

I'm running a 350ZZ4 with FIRST TPI fuel injection with a 700r4 and 3:73rear. The truck returns around 17mpg at 75mph. It's not a daily driver, but over the past 3 years I have put around 11k mile on it without issue.

As far a longevity, the SBC utilizing fuel injection will run longer that a carb version because you don't get raw fuel washing the cylinders during start up like a carb engine will. I ran a 95 GMC with a factory 350 SBC TBI set up over 260k miles and it ran just as well as when new. I did maintain it well and ran synthetic oil from day one. I also had several friends with pickups and suburbans that ran well past 350k miles from the same engine set up. So, I don't think longevity is a real issue with a SBC when using FI. Plus many of these trucks never see a lot of milage anyway.

Here's a pic of my set up.

[Vegetta]

Thanks for all the replies. The crate option seems the best for the $ I have available. The motor in it know is a Jasper 350. It runs great but I cant get the main seals to stop leaking. That's why I'm wanting a brand new motor and not a rebuilt one. The truck looks to good to have a puddle of oil left everywhere I go.

[NaturalSnapple]

If it doesn't have to be a new engine you can get a 6.0L LQ4/LQ9 for a bit over $1,000 with the harness. You're getting the improvements that the LS series engines have but with an iron block.