besides the fact that the above statement is flat out wrong...what he fails to see is that some of us do in fact enjoy getting our hands dirty in an effort to try something new and different, and if along the way, a hybrid LS2 w/ LS6 heads and cam happens to make 50 more at the wheels than a fresh LS6 replacement...well thats just a bonus. I plan on doing all the work myself on this project (excluding tuning obviously) so the process is as much the point as the end result

 

anyway, getting back on track...as far as the heads go, I too was under the impression that the LS2 heads were the same castings as the LS6s, just didnt have the light weight valves,etc. However, if I do go with the 402 shortblock, in an effort to save some cash, I may just go with the CNCd LS6 heads from GM...I think the set is something like 1800 bucks, with no core exchange required. Ive also been considering the GM Hot Cam...mainly because this will be a daily driver and the reccomended spring for the Hot Cam is the stock LS6 spring...somewhat simplifying things and Ive never heard of anyone with a Hot Cam breaking an LS6 spring. Also, for some reason, I think it would be cool to do this entire project with parts from the GM catalogue (I have no real reason for it, but I still think it would be cool)

now back to the knock sensor issue. If Im correct (which is rare) the problem is that the LS1/6 had knock sensors and the LS2 does not??? If someone can varify, please do. So how exactly would one go about getting around this problem?? Running a motor pushing between 400-500 hp without knock sensors seems like a bad idea to me, but if someone who knows more about the subject than I could chime in, it would be much appriciated.

as far as the cam sensor goes...I believe it was moved to the front of the LS2. Does that mean all that has to be done is to fab up and extension for the stock LS1 harness so that it will reach the front??

I think Ive settled on the LS6 intake/TB based on cost, and the performance numbers Hot Rod magazine got out of an LS2 with that set up. So Im assuming that should be plug and play as well.

Thanks again for all the help guys....and keep it commin

 

The LS2 has knock sensors that are located external on the motor just under the exhaust manifolds on the outside wall of the motor. The sensor bosses are a different thread than the LS1 sensor is. But more importantly, the knock frequency generated at that particular location from bona fide knocking is different, thus requiring a sensor of a different crystal design. So, this makes the LS2 knock sensors incompatible with the LS1 electronics, I believe. You can certainly run the motor without KR, no problem. Many of us that tune sometimes sensitize or turn off KR on big tuner motors, especially with Speed Density tuning.

The Cam sensor is at front of motor but the plug and sensor is same as LS1. Just lengthen the harness.

If you go with LS2 intake and/or TB, you have to extend the MAP sensor harness because the MAP sensor is at front of intake. And you also have to reconfigure/rewire the LS1 TB harness to be compatible with the LS2 TB. Shirl Dickey has all this info, as does Andy I believe.


Robert / Gen 3 MS

 

you're right, it would be a very bad idea. I think what they were saying is the the knock sensors in the LS2 are in a different location and you'll have to deal with that.

another thing that MUKAKsC5 doesn't know is that the LS2 has a broader torque curve than an LS6, so it would be a better engine for street driving. The LS6 makes all of it's power at higher RPMs, so you've got to be at the track to really use it. "There is no replacement for displacement"

 

With a safe tune and a reasonable compression ratio you can get away with out the knock sensors.

Just have to make sure you use quality gas and not push it if you start to hear any knock what-so-ever.

This fact would not scare me away from doing this conversion. The upside for power on a reasonable budget is too good!!

 

well, I finally read through all 30 some odd pages of the post over on LS1tech.com Like you guys said, with a conservative tune, and good gas, you dont need knock sensors...apparantly Ford still doesnt use them. On the other hand, apparantly a bunch of the Fbody guys have come up with a way to make the LS1 sensors work in the LS2....involves rethreading the holes though. What I think Ive settled on is the 402 short block, with CNCd LS6 heads, GM Hot Cam, LS6 intake and throttle body. I think this will be a good compromise between a very strong motor and doing it on a budget. Its going to be a daily driver, so I didnt want to sink a lot of money into exotic heads with a higher compression. I want something thats going to be both affordable and reliable. Im going to email SD on Monday to run my plan through them and see what they think. Now I just need to sell this truck of mine and find a suitable black 1999-2000 FRC. Anybody need a truck???

 

Everything works. I have a C5 cam sensor and C6 Knock sensors on a C5R block and have zero issues.
Same with the LS2 throttlebody. I use them on C5s all the time. Just use a FAST manifold. (The LS2 manifold blows) 2 wires are not used and the other six are just soldered and heat shrunk to the old harness.
Too bad the stupid pigtail is so expensive. Retail is like $130. That's ridiculous.
The cam sensor wires will have to be extended, and also re pinned. Not only do " A B C and D" do different things, the color coding is different. It took me a little while to figure it out.
The knock sensors will require tapping holes in the block to match. They may need to be desensitized, but probably not.
Remember, audible knock is often not picked up by the sensors anyway. It's at a higher frequency than the sensors are tuned for. I hear cars that rattle like crazy and have no KR.
Just some notes on the LS2. The heads are 01 LS6 heads. They dont even open the chamber to fit the 4" bore. The cam is also an 01 LS6 cam. Just changing to an 02 LS6 cam should be quite an improvement.
They probably did this so that they can bump up the HP in the next model year. That and the fact that they wanted a big difference between the C6 and new Z06 to justify the price.
Bottom line is, I wouldn't be afraid to do the swap. I made the change back in October ( maybe November) just to see if it could be done.

 

If you already have H/C on your LS1 and just swapped the shortblock for the 402 what kind of increase would that yield?? 50rwhp??

 

Andy, thanks for the info, after I have parts in hand I may be calling to pick your brain about a few things since you seem to be ahead of the game on this one

 

That is very interesting. Do you suppose the LS7 crate motor will require the same changes you just described for the LS2 - or more?

 

[QUOTE=rwj383]Your right Its A no brainer, thats why I went with that route I now have a LS2 402 stroker for my TT. I was going to forge my 98 LS1 and found out that for A few hundred bucks more I could have 54 more CI and A much stronger and better breathing block, the only thing I had to change is the postion of the knock sensors and extend the cam sensor for the new front cover.
Oh yea you can still use your LS1/6 PCM on the LS2.

 

Its not that hard. I was taking apart an A&A 427 this weekend and putting stuff on Andy's new 441cid motor. The knock sensors go right on the side of the block. The cam sensor has to go in the timing cover over the gear. I will double check that with Andy though because he had finished that part before I got back over to watch him. But his 441cid is going into his C6

Next time I have build up a motor for my car it is going to be a 441cid LS2....running the same amount of boost...should be interesting.

 

thanks for the info, definately keep us up to date

 

mmmm? i think your right. but it seems the thread is leaning towards a short block swap anyways, so oh well. But yea, i would have to agree, i have read that they are pretty much the same.

I definetly plan to do this block swap in a year or two or whenever the ol'LS1 gives out.

 

 

FlyNavy- if you will still be in town when you start this project, and you want any help, let me know. I love getting my hands dirty. I'll keep my eye out for a FRC in black, too.

Scott

 

Just picking up on Andy's post above. Are the 01 LS6 heads and the 04 LS6 heads the same?

Tino

 

THE BENEFITS WOULD BE THE DIFFERENCE between 383 and 402
Without re-sleeve
I'm not a fan of Darton wet sleeve in ls1
Dry sleeve in ls2 not tested ,remember dry sleeves in the Ls1
Next and the best c5r
Ls7 might be great no prices yet.
My .02
John Sr.

 

This sounds like opportunity knocking for someone to build/sell a kit to make this swap. Keep it simple,, just package it all in one box with a set of instructions. Ummmmmmmmmmmmmmm

 

See my thread LS2 swap (type Swap) into search window or my login name. Call DTE in IN they are doing it for me. I think it is a good move. Some say I should have done 383 stroker, but when priced, the 383 came out 5-7k more with minimal HP gain.