My LS2.5 Rebuild

[Petro]

I think I've decided on a cam to go with my LS3/L92 head swap on my LS2.. It's similar to SweetS10V8s...Hell I could even just copy him and go with his cam selection...I also plan on going with the Lingenfelter CNCd LS3 heads with hollow stem intake valves. Springs will be Comps 26928s. I'm going to use stock rockers. ( Yella Terra shaft rockers may be a future mod?!?! I've read they are lil quieter.) I want to keep the stock compression. I have no problem with having to flycut. So should I go with this cam from SLP or the LSr Comp Cam? Any opinions on what size combustion chambers I should go with? I'm thinking 65cc....


Comps LSr Cam

SLPs CAM

[Petro]

I also posted this for discussion over on LS1Tech but what is everyones opinion on honing with either Silicone Carbide or Aluminum Oxide?

[SweetS10V8]

You wont ber sorry if you go the route I did! Its amazingly fun!!! better than my '89 w/ 350 + 250 shot!

Personally I might go a tad smaller on exhaust duration if you do not port the heads(just to quiet it down a tad). I had them on the flow bench and they flowed 245cfm with no exhaust tube at all, they flowed 250-260(on a Superflow 1020 bench) with a 1 3/4" tube when i mearly held it up to the port!

The LSR cam is incredible, It makes me smile daily! I give up some HP with my small cam. But I dont have to post 500+ rwhp on a forum to make me happy. Torque is a good thing on a daily basis! Ill give up a lot of power the 2-3 times a year Im at the track vs the 99.99% Im driving it on the street.

Now is youwant all out power there are much larger duration LSR cams that fit the bill......

[Petro]

Don't get me wrong I'd love to get the most power I could out of it. But I also want driveablility. And since I'm not a cam expert by any means I originally started out by looking at the Livernois Stage 2 or 2R Cam..Similar to the cam that was used in the GM Hi-Tech I read. Then with some searching I figured I could go a different route and mill the heads to get the original compression with a smaller cam. Mind you I am not a professional at any of this but I try my best. I do LOTS of reading before I post and will take any opinions. Like I said I would like to make power with driveability and without a big lopy sound.

[philntx]

Driveability and decent manners in traffic are the key for me. I would rather give up a little power ( how often do you go WOT on the street in traffic) and have a smoother running vehicle.
One of my friends on the corvette forums recommended this package for me for another project I'm working on. (not an S10)
6 liter LS2 short block
UnPorted, stock L92 heads (milled .030)
224 XFI/ 230XFI 114+2 cam
Cometic .040 head gaskets
ARP head bolts
L76 intake manifold with 90mm Throttle body
40lb injectors

Normal other items......

This combo would produce about 440-450 HP and 420-440 lbft torque.
Would idle around 750-800
Would work with an automatic trans.

Here's a video of his vette in action, but with a 228 / 232 114+2 LSA Comp Cam and 6-speed trans with 4.11's):

http://www.youtube.com/watch?v=DBmFS...layer_embedded

I'm also looking at this cam: TR 214/230, .601/.579, 117
This one will have a smoother idle than the first one.

The Livernois equivalents are the Stage 1 for the first cam and Stage 1C for the second cam.

The 2R will shake your teeth out in an S10. (my opinion)

[Petro]

They all seem like nice choices...I just have to make a decision... ...I could go with unported heads and save money or go with ported heads which in turn affects cam decision...

[Petro]

All that Cometic has listed is a .051 Gasket 4.060 Bore...Am I not looking in the right spot? The 4.060 should be fine as there will only be a .005 overhang into the chamber right?

[philntx]

I've got a .043 on mine currently.

Felpro or any of the majors has one you can use.

[philntx]

Quote: Originally Posted by Petro

They all seem like nice choices...I just have to make a decision... ...I could go with unported heads and save money or go with ported heads which in turn affects cam decision...

I think the choice is pretty easy.

Just compare the flow numbers of a set of non-ported L92 heads to a set of ported heads.

Flow numbers of the stock L92 head. Tested by Livernois Motorsports
Lift Intake Flow Exhaust Flow
(inches) (CFM) (CFM)
0.1 79.2 57.8
0.2 153 114.4
0.3 225 147.2
0.4 276 170.3
0.5 309.6 183.1
0.55 323.2 186
0.6 332.2 189.5

I think they do pretty good, when compared to CNCed 243 heads.

Lingenfelter and WCCH heads are some of the best units on the market, but if I was "cash-flow challenged",
I wouldn't feel bad with a set of stock L92's with a set of good springs and titanium retainers.

[Petro]

Then I may just go stock LS3 heads( hollow intake valve) with upgraded springs...and mill them..the 918s will be enough..but the 26928s may be better...The wife would like those $$$ numbers more so with that setup than the one I have been looking at...haha...

[Petro]

I just saw that Mast Motorsports sells a CNCd 12 degree LS3 head with a 2.200 intake and 1.610 Exhaust Valve!!! Just thought I'd share that..Although some probably already know...I know they wouldn't fit but pretty cool stuff...

[Petro]

Got to come in and take a shower and refit for a few days!!!! Anyways...I've got a few more parts to order and will begin honing and cleaning the block when leave starts around 24 Aug...I decided to go with stock LS3 heads..but still tettering on the cam...Oh and I also found some .040 cometic head gaskets with a 4.060 bore..That should be good enough right? The .005 shouldn't get in the way? Thanks

[SweetS10V8]

The 918s work great with that cam, as long as you get the intake valves. Comp also makes a tool steel retainer that is about the same weight as titanium #1772-16. Thats what Im running.

Remember if you get that cam the part number will end up being 54-000-11. Thats the part mine was. Because its a "Custom" cam, the cam you linked to is a single bolt LS3 cam, and you need the same cam on a 3 bolt cam core.

I also think a non cnc set of LS3/L92 heads would be just fine.

[Petro]

Would the 26928s be much better than the 918s? The new 918s do have more more max lift than the old ones...But I've read some good reviews about the 298s...Is there a specific set I need to buy for the LS3 heads? So I need to order Retainers and Locks also..anything else for the heads like seals I need to get? Oh and thanks for the heads up on the part number for the cam...Yeah I knew that you got the cam "custom" ground since the original one is a single bolt cam...

[Petro]

Just got back from the field!!!!! Will be ordering parts like crazy in the next couple of days!!!! First up LS3 heads!!!!

[Petro]

The heads are coming in...I'm sure SweetV8 will be able to verify but these look like the lightweight valves correct? And The XER273HR may be the way I'm going...It seems to be less expensive than the Livernois Stage 1...Any idea why?

http://farm3.static.flickr.com/2463/...661d65.jpg?v=0
http://farm3.static.flickr.com/2453/...eb28a2.jpg?v=0

[Petro]

Oh does anyone know the Part # for stock LS2 piston ring sets? Thanks..

[Petro]

Found the number for the rings....But would still like to know some opinions on the 928s VS. 918s....And which particular set I should purchase...With milling the heads and the thinner head gasket will I have to go with shorter pushrod? Or will the stock 7.400 length be fine? Thanks

[Petro]

I'm a Post .... haha... Well I guess I'm on my own...But I should have stated in the post with LS3 Head pics that the reason I'm sure they are LS3 and not L92 valved is because they are shiny/polished looking...I've read the the L92 valves are dull and don't have such a nice finish on them and they usually have 2 paint dots instead of just the LS3's one...And I plan on using a pushrod length checker but just wanted to know if anyone would know how the milling and thinner head gaskets etc affect it...I am by no means a engine expert but I try to read up on everything although some stuff I still don't fully understand...Any help or FYIs are invited...Thanks..

Oh and I should be assembling the shortblock this coming week!!!!!

[Kampz69]

nice man, post up a bunch of pics of the assembly

[Petro]

Maybe this will encourage some input...

LS3 heads , tools , Accell Truck Coils , etc.....

[Petro]

I've updated my build thread more so than here..Plus it would lots of double posting..anyways I just bought some LS7 lifters and they are different than the LS2 style..Went with new ones since I figured might as well while I have it apart... Check it out:

[Petro]

Is the Red oil pick-up o-ring better than the Blue one?

[CODE4LS1]

Quote: Originally Posted by Petro

Is the Red oil pick-up o-ring better than the Blue one?

The red is a bit thicker than the blue one. I used the red on mine

[Petro]

Yeah I knew that the Red one is thicker but does that mean better? I've got the girdle from BRP already...I dunno may just stick with the blue one I've got...Anyways would someone by some crazy chance know the piston ring end gap for stock LS2 piston rings???

[Petro]

Does this sound about right? I plan on putting this thing together starting tomorrow...

Piston Ring End Gap - First Compression Ring - Measured in Cylinder Bore - Production
0.20-0.41 mm
0.008-0.016 in

Piston Ring End Gap - Second Compression Ring - Measured in Cylinder Bore - Production
0.37-0.69 mm
0.015-0.027 in

Piston Ring End Gap - Oil Control Ring - Measured in Cylinder Bore - Production
0.22-0.79 mm
0.009-0.031 in

[LS2Sonoma]

16 is a bit tight especially if you are gonna be driving this thing hard. depending on piston/ring manufacturers they generally recommend 4 - 5 thou per inch of bore for na

i wouldnt set those tighter than 20. second ring gap isnt as important but make sure its not smaller

if youre planning on juice ever, go bigger 6 - 7 per inch for the top 7 -8 for the 2nd

[Petro]

I'm not a professional engine builder and this is the first engine I've ever put together completely by myself...So some of this stuff is new to me...So please bear with...Now I need to find out which way to place the 1st and 2nd compression rings..(with dot side up or down??) 2nd ring has a beveled edge on opposite side of dot...

This is where I got my info from:

http://www.aussiev8.com.au/holden/55...ine-specs.html

And another site that I've looked at:

http://www.aa1car.com/library/ring_end_gap.htm

[LS2Sonoma]

if the rings have dots, then the dot faces up

[Petro]

I did a quick check on cylinder #5 and 1st ring= .018 and 2nd ring= .027 too large of a difference???

[Petro]

The bore taper on #7 is .005 already ....Here's a pic of #7 and #6....

[Petro]

The pics look worse than what it looks like in real life...The smallest gauge I've got is .0015 and if I tightly lay it across a flat surface I can definitely feel it and catch my fingernail on it...So the markings are less than .0015 deep...

[LS2Sonoma]

nah, that ring gap is ok

woah cylinders! was that corrosion?

[Petro]

Yeah there was some slight pitting...I also read this article and it seems like it's not too bad...What's you opinion??? Keep honing , it'll be ok , pros/cons...etc...???

http://images.google.com/imgres?imgurl=http://k53.pbase.com/g3/05/317005/2/53355220.P1390709.jpg&imgrefurl=http://www.pbase.com/stealthfti/image/53355220&usg=__sLCaUeJDHrLW0WJx61ZgnJlHTTw=&h=688& w=800&sz=63&hl=en&start=3&um=1&tbnid=ve3cbnG2vKyti M:&tbnh=123&tbnw=143&prev=/images%3Fq%3Dcylinder%2Bwall%2Bpitting%26hl%3Den%2 6um%3D1

[LS2Sonoma]

have you checked bore size and piston size yet? whats your clearance at now?

you dont want the holes to get too big, its just hard on the piston

[Petro]

I may need to go buy some more tools..But after some more reading and other suggestions/opinions I am confident that this isn't as extreme as I originally thought it was...I cleaned the block throughly and plan on doing pre-assembly starting tomorrow...But after I washed the block I got some "flash" rust on the bore walls and it won't clean off with mineral spirits and rag...I wonder if I should go back over them???

[LS2Sonoma]

yea, make sure its free of rust. at work we coat the cylinders with wd40 until the block is ready to assemble. your new rings dont need any rust help seating in the new bore lol

[Petro]

Yeah I was like WTF after I washed it with soapy water...Then I took my brushes and mineral spirits to the block...Went over it like 5 or 6 times...It's clean now but I'll have to go over it again after a few quick swipes on each one with the hone to take that flash rust off...

[Petro]

How concerned should I be about this crack? It's down by where the stock A/C compressor would mount.

[LS2Sonoma]

wouldnt worry about it at all.. is that an aluminum block i see? wheres the pix of it?

[Petro]

Yep it's aluminum...went ahead and started putting it together:

[LS2Sonoma]

right on mang

[Petro]

Do you think I could benefit by using Total Seal's "Quickseat" ...Or is the stuff a gimick?

[LS2Sonoma]

ive never even heard of it but if you have some you might as well use it

[Petro]

Forum member JimJim came over today and let me drive his LS6 2000 Extreme S10 Ext Cab and it gets up and goes!!! Thanks for the drive Jim...


Oh and I may just go ahead and apply some of it...I'll have to order it though...

[LS2Sonoma]

just get that thing built already!!! break in the rings the old fashioned way

[Petro]

Shortblock is assembled!!!!

[LS2Sonoma]

is it running yet? lol

[Petro]

Quote: Originally Posted by LS2Sonoma

is it running yet? lol

haha....Unfortunately I probably won't be able to install it before I deploy again in about 3-4 months...

[LS2Sonoma]

why so long?