LS-1 Conversion Problems

[Briguy280Z]

Any help would be nice!

 

Status: Engine, electrical, radiator and fuel is in. Ready to go.

 

I noticed that the throttle body has a coolant running throught it. Is this nessessary or can I just cap it off the return line!!!??

 

Problem:

First step i took in starting the engine was to check the fuel to make sure no leeks were present...! I was ok!

 

Second i wanted to make sure the oil pump and pressure was going to be good. I took all the plugs out and turned it over for about 20 seconds. Oil pressure guage never showed anything...getting kind of nervious i checked the oil filter to see if any oil was present. (there was not a drop of oil ) so i filled the filter with oil. So far i have no oil pressure anywhere. Where should i look first or am i being too parinoid? I wanted to prime the pump and engine first before starting it but it is an electrical distributer and no way to turn the oilpump externally. What is the best way to check to see if there is any leeks in the system?

 

 

 

FYI

 

In 99 the camaro fuel tanks changed back to a fuel rail regulator with a return line at the fuel rail. In 98 the fuel tank had a regulator at the end of the returnline so you would have 2 fuel regulators one in the front and one in the tank. I got a tank without a fuel regulator and an engine without a return fuel rail. I can eather replace the fuel rail (i took out the return line already) or install a regulator on the return line going to the tank. Just something to think about if you install a camaro gas tank.

[Guest Anonymous]

You can bypass the coolant thru the throttle body. I don't know about the oil pump.

[Guest Your Car is Slow]

Bypassing the throttle body coolant passage is a common mod.

 

It enters one side and exits the other...you can search on LS1.com for easy procedures in rerouting the line.

[Mike C]

I assume you checked the dipstick?

[jeromio]

Just to be clear, the coolant does not need to go thru the throttle body, BUT, don't just cap off that line. You need that line to end up back in the radiator as it is apparently important for coolant circulation thru the heads. (temporarily, mine is capped off - long term, mine will plumb to the upper rad hose).

 

Oil pressure - check on LS1tech.com. I recall seeing a thread on how to prime an LS1. (I'm sure there's good tech on LS1.com, I'm just damned if I can find it - ls1tech.com is excellent) If you want a sanity check, try hooking up an ohmmeter to the pressure sender and crank it over. If you get no reading (and you're game for a mess), try removing the sender and turning it over. If you get no oil spraying out of that hole, your motor is in big trouble .

[Briguy280Z]

Good news,

 

I pumped some oil into the engine with a oil pump and hoped it would prime the pump. Turned it over and at first got a little pressure, and after awile got about 30psi. Of corse this is cold oil pressure. I should see quite abit less when its warm.

 

Thanks for the info on the throttle body

 

Good place for good info!!!

[jbeech]

Not to be flip, but what advantages are there to an LS1 over an old-style SBC?

[Guest Your Car is Slow]

Fuel injection, weight and power (stock for stock anyway)

[Mudge]

Unless you equip an older SBC with 15º heads, then the LS1 will kick anything elses ___ GM wise. These cars can be setup to make big power with no real exotic work, plus the firing order is 'better' for those picky about that extra 1% or so from exaust pulsation efficiency/velocity yada yada.

 

Basically the LS1 is setup almost perfectly right off the bat with what the SBCs only get with machine work and plenty of dough, plus the whole fuel injection thing, carbs make me sick. For an all out race machine thats one thing, but I was making on the (dinosaur) LT1 about 470 HP and getting 17 MPG average, on trips I'd touch into the 20 range, I want to see someone do that with a carb setup. As a joke, "the carbeurator is the only device known to man to provide an innaccurate air/fuel ratio at all RPMs." Better driveability, no fuel float issues in corners, you name it, FI IMO is the sheet.

 

Port the heads, throw in a cam, and make an easy 500 HP if not more. There are guys doing over 500 RWHP with more work (too bad the internals are so expensive).

 

Guys making HP like I did with my LT1, are running 10-15º smaller cams, and no headwork are pushing 400 RWHP, passing the sniffer in CA. I am very tempted to get one myself, throw on some LS6 or 6.0L truck heads ported, work the intake possibly (they are not perfect), and someone could find themselves with good driveability, "good" MPG, and 600+ HP depending on your wants, with an under 7k limit if so desired.

 

All aluminum and 6 bolt mains, FWIW.

 

For a GM engine it is top dog, no question about it.

[Guest Your Car is Slow]

Eh..id say the LS6 is the top dog for the GM fleet

[Mudge]

Yeah, but its basically a top end package, and is out of the range for most of us folks. Even the LS1 is pricey, I'd rather buy the whole car and just enjoy it as is, maybe with mods, but I'm not ready to have a $10,000 Z car just yet. So many mods, so little money!

[jbeech]

I presume the LS6 is the Corvette while the LS1 goes into the Camaro and maybe the lower-end Corvette package too. So, does an LS1 weigh more, or less, than an equivalent SBC? My math says adding 1200 bucks for good heads, plus 600 for roller cam/lifters and rockers, plus another $2200 or so for a MPI FI set up and we're back to even right, i.e.about $4k to convert an old-style SBC? They're still both OHV engines, so we're back to the weight question for that AL block plus the attendant difficulties of retrofitting the LS1 engine into a conventional SBC engine-mount engine-bay.

[Mudge]

Of course its less, all aluminum block, heads, and a plastic intake

 

So, does it weigh more or less than an equivalent SBC? Adding 1200 bucks for heads, plus 600 for roller cam/lifters and rockers, and another $2200 or so for a MPI FI set up and we're back to even right, i.e.about $4k to convert an old-style SBC?

 

Your not just buying roller lifters for an old block either, that is going to cost more in machining as well. I assume that the LS1s have less lobe lift and more rocker ratio to avoid lifter float, again another advantage. Plus on a small scale it means less rotating mass for the cam, probably not much of an issue although at high RPM it will reduce cam torsion. I'll bet they can improve ramping profile as well! Making it run probably similar to a solid.

 

Ok, now lets add up cost of 15º heads that will flow like no f'ing tomorow, cost of fabricating a polyplastic intake that will match the heads and flow like an LS1 or LS6 intake if you wish (2000 or 2001 cars get LS6 intake also). No matter how you work things if you can find a used LS1/T56 setup for $3000-$3500 you are getting one heck of a deal, its still out of my price range though.

[jbeech]

No offense Mudge, but I'm wary of "of course" statements. Does anybody have hard numbers? Cranks, rods, pistons, headers, etc. are considerably cheaper - with loads more variety (for the conventional SBC) so all things being equal in the power/convenience department, weight becomes the remaining issue as with its more forward mounts, swapping one in isn't as easy.

[Mudge]

Yes, considerably cheaper internals, another disadvantage to the LS1.

 

Yes I know for a fact it weighs less, find the numbers online via search. The front end of an LS1 car versus an aluminum head/intake LT1 is about 65 pounds less, and there are basically no other differences between the two cars as for the front suspension. An aluminum block is going to weigh less than cast iron, no science there. The intake, also more weight removed, the LT1 aluminum intake is a bit large and is around 30 pounds, plastic is obviously significantly less.

 

These cars can pull about 390-400 RWHP with NO head work and a 222/230 cam. That beats the LT1 by a fat margin. It took a semi-large cam to get my ported head LT1 to pull 411.

 

Due to cost, as well as them being relatively new engines, I can't see rebuilding an LS1 at all unless I was throwing in rings/bearings.

[jeromio]

I got my LS1 with 34Kmiles, a 4L60E, PCM, etc. for $2K. It had some damaged parts (from the wreck) that cost about $200 to replace. I had my PCM tweaked for another $300. That was a tough call - a one time $300 charge, or $550 for the ability to tweak and tune at will (LS1Edit).

 

You can "duplicate" an LS6 with an LS1 by replacing the intake and getting the heads ported (or buying some). The aftermarket for LS1 is pretty big for such a new engine. There's lots of parts available. There's also an aftermarket LS6 intake cast from Aluminum which can be port matched to the heads. Either one costs about $400.

 

I think the only thing going against it is the limited availability of parts/info on the swap. As an engine, I'd say it's unmatched in price/performance. In my Z, I anticipate some nice little gains over stock via a much less restrcitve intake and exhaust.

 

(I am slightly biased)

[Mudge]

I dont know of anyone running past 7k or so on the LS1 (PCM can take it to 8500!), but I do know of 470 RWHP LS1 cars (heads/cam/program). When Tunercat finally has something to offer instead of $550 LS1 Edit, then we have something that I will really be interested in.

 

6.0L truck LS1 heads are also capable of LS6 flow numbers, comparing a ported head to ported head. When you rip into the heads and start welding, I have heard of 360cfm or thereabouts on LS6 heads. Not very difficult to get a streetable 650 HP out of one of these cars, its f'ing ridiculous, and yes I'm jealous 8)