steve40th

This thread is digressing.
My 396LT1, 500hp motor, was around 12000 bucks, complete, when new in 2001.
Now, if the LS1's at that time were really as popular as they are today, I would have done the swap. But now with my measly 500hp'sih engine, the only benefit is a more docile user freindly engine with the same HP.
I think going from my CNC factory heads to set of AFR's would yield the same benefit of more docile engine. Regardless, LSx engines are a great leap forward, but not feasible to me unless it was a drop in plug and play.
Hell, people still hot rod Ford Flat heads

DrEvil11417

i did a ton of research on swapping a lsx into my old 86 but wasn't able to find anything that would be a plug and play, imo it seems like more trouble than it's worth

Mojave

This post is full of fail, with fail sauce, with extra fail dressing.

LT4's are close, but generally a bit lower than a stock LS1, but that is far from the whole story. A cammed LS1 with headers is 400 RWHP, I've seen several local cars do it. A stock LT4 with a cam will not touch that, the heads just don't flow enough stock.

L92 is a conservative 403 crank hp, but throw in a cam, and you are over 500 crank hp easily, solid 450 RWHP. I'd prefer an L92 to an LS2, since the LS2 is still cathedral port heads and the L92 is the better square port stuff.

Why wouldn't an LS2 fit? It is the exact same size as LS1, LQ4, LQ9, LS3, LS7, LS6, LS3, and every other LS engine: they area all THE SAME SIZE AND BOLT IN THE EXACT SAME. Same deck height, same block size, same mounts, same everything.

LS7 create engine is quite expensive, but it's dry sump. You can easily make LS7 power with square port heads and a set sump for 1/3 the cost. If you want the dry sump, LS7 is actually a really good deal, as over 600 RWHP is very doable with a cam-only. I'd LOVE to see you do a dry sump LT4 with only a cam do 600 RWHP NA.


I have an LT4, and I almost swapped it out. Why do you guys need a kit? Buy the headers, motor mount, wiring harness and get someone to fab a c-beam mount.

mnstrlt1

much easier said than done!

the Ls-x is nothing revolutionary! It's simply a series of learned information that was finally applied to a mass production motor (i.e. making the technology readily available- CHEAP). The heads are far more advanced than the traditional small-blocks, BUT we're comparing an 18 degree (in some cases 15 degree) head to a 23 degree head? Of course you're going to get better flow!

My point is that a traditional small block, dressed up with the equivalent components (primarily the heads, like 18/15/12 degree heads) will likely pump out ridiculous amounts of power as well!

Of course with the different head geometry (on a gen-I and gen-II) you'd also have to take into consideration the cost of a new intake manifold (to support the new heads) and a new set of headers (to again work with the different angle of the head). this would start pushing the "practicality" envelope and a reasonable "budget".

Yes, the LS-x IS far more advanced than the gen-I and gen-II when we're comparing stock to stock (off the production line). No-one is arguing this fact. the argument is that the technology (18/15/12 degree heads) are readily available for the gen-I (not so much for the gen-II), so that you can "still" stick with your traditional small-block platform.


bottom line: a stout gen-I and gen-II can easily be had for a fraction of the alloted budget listed in the OP. And *if* we're talking about a boosted application (or any power-adder) than you can toss most of the details out the window.

Mojave

While SB2 and SB2.2 head certainly get the job done, good luck finding an intake to clear a stock C4 hood. You are likely going to use a carb, as stock TPI or LT1 electronics would not work well with such a setup. Also, custom header work needs to be done to mate up to the heads. So compared to a carb'ed LS1 (which is silly but definitely doable), the difference comes down to motor mounts (which you can buy and bolt on) and a c-beam mount.

I'm not saying than an SB2.2 won't do the job, but the amount of work is surprisingly close between the two and you get an aluminum block. Yes, you can get SBC aluminum blocks, but they are pricey compared to LS1 stuff.

melrose

That's all I was hoping for. If any of you want headers, LS swap or not, just give me call.

abc 123

Sums up the entire thread.

subtlez28

I'm kind of kidding calling it a race motor. I just mean that a comparable SBC would be a race motor. Stock LS1s are rated 325-345 hp, but it is well know that they are under rated as they normally dyno at ~310-320 to the wheels. Assuming the 85% rule (that 15% flywheel HP is lost to drive line and friction) that is 365-405 flywheel hp. More is available w just headers and a tune. 400 plus RWHP is only a cam and heads away. To pull of these #s, and to have an aluminum block in a SBC requires aftermarket parts, and really would be a "race motor".

And that is just the LS1. If you have the cash for the LS3 or L92 a cam alone will put you in 500 flywheel HP range with a very tame street friendly engine. Add some ported heads and a hairy cam... sky is the limit.

In 5 minutes of looking I found a LS1 long block with an LS6 cam for $1000!!
http://www.ls1tech.com/forums/lsx-pa...w-ls6-cam.html

And pull out 5.3s run in the $500-900 range.

These engines are a huge performance bargin! Just look at this thread. Even the nay-sayers need to compare SB2/SB2.2s and expensively modded LTX engines just to out do a stock LS engine. Go find me a SB2 long block for $1000...

mackeyred96

C4 owners just don't spend money.

_twisted_

come on John - some of us do

abc 123

Whoa there chief. There is too much honesty in that reply.

Crepitus

My situation; well worn cross fire / 4+3 hmmm vs Ls1 / t56. in Washington a 84 doesnt have to pass smog, a C5 will. A nice sbc with a carb is not out of the question, yet.
I am listening very closely. Thank you very much to all for constructive comments.

mnstrlt1

the C5 corvette has to pass emissions, but for me (here in AZ) the emissions station only plugs an OBD-II scanner into the OBD-II port to verify that everything checks out "alright" (no emissions related codes). It's literally 3 minutes for them to "emissions check" a 96' model year vehicle or newer.

I've known several guys running without cat's, heavily modified, etc. that get through emissions without a problem. the reason for this is because the information that the emission station is looking for can easily be manipulated by a shop that does dyno-tuning or any sort of programming work to the stock computer. i.e. you can eliminate the cats out of your c5 corvette so that the computer doesn't see anything wrong with them missing rather than displaying a "check engine" light on the dash. Totally easy to manipulte.

an 84' with the cross-fire and 4+3 would make a good candidate for the swap though.

subtlez28

I agree that a well worn 84 is the perfect candidate (coincidence: I am doing a swap to an 84). Odds are most of them have issues w the digital dash anyway. Not to mention HVAC and general interior issues just from use and age.

Now that said, my dad has a very nice 84. It would be a shame to gut it out. Same as it would be to gut out say a nice 94. The point that may have been missed here is this cheap swap idea is great to bring life and fun back to a worn, older, less desirable C4s.

I will be shocked if when I'm finished someone says, "Man, you should not have taken out the crossfire!". Seems like an LS1 powered 84 that tears up the road course and runs easy 12s in the 1/4 would be more desirable than the original.

Some people like corvettes because they have cool electronics, creature comforts and the like. Others, like me, like the design, light weight, and parts availability. The idea of a stripped to basics (no digital dash, no power locks, no HVAC, no stereo) appeals to me. I'm positive I'm not alone (anyone seen Mojave's car)?

Mojave

The digital dash will work with an LS1, the only features that will be lost are the instant and average MPG functions.

steve40th

Its all about goals with your Vette, and finances. I cant even afford little stuff anymore.
Too many of my dependents in college etc.

Crepitus

We are still talking about my car right.

Crepitus

Thanks for the heads up on the OBDII smog checks.

One prob I see with the stock dash is that the tack only reads to 6000. A switch to anolog seems pretty easy and is high on my list of must have.

mnstrlt1

honestly, I would start with a new harness (like a 12-circuit harness), and just rewire the entire car. If you're ditching a lot of details and going with an Ls-x swap and computer with analog gauges. this would be "the right" way to go about it, instead of cutting and splicing etc.

of course, my idea of an Ls-x swap into a c4 would also INCLUDE a full restoration (down to the frame).

USAsOnlyWay

Guys, really the LS motors are race motors compared to the SBC, just like how roller rockers once were race technology etc etc. It is race tech that has trickled down to production.

Better block, better oiling, stronger camshafts, better lifters (which we can use, yes), an aluminum block, 15* heads stock.

So forth and so on, an AL Dart block is what 2k? Then you have sleeving slip issues and so forth.

As far as parts interchangeability if we just do the research, the info is out there...

http://www.crateenginedepot.com/stor...hart_large.jpg

I'm still tossing up whether to go LS or big inch SBC, however, I think a L92 headed 402 would do pretty well, especially once direct injection comes out. (Which it is coming, the C6R was using it in racing earlier this year and it was removed until standard on production Vettes... )


http://www.prostreetcustoms.net/CorvettePage.html

Also, guys the T56 adapter exists already. Now you get a 6 speed (4+3/auto guys), you loose weight (worth more "power") and you get more power and reliability. And like someone else said, if you do a standalone engine management/or a new harness well, done and done.