Ill Be Doing Full Exhaust And A Cam Soon , Would It Be Worth It To Get Some Ls3 Heads Bore Them Out And Put Them In Aswell?

 

ttt..

 

Hi,I been a CF member for years.I seen the ttt many times.What does that mean.

 

TTT = to the top.

OP: (edit, see you've got a C6)It depends on what you're looking for. It could be debated for hours on what is the best combo, but it boils down to what you're looking for. The LS3/L92 setup is awesome for the money, but you can get more power out of different heads. With the L92 heads, you'll have to have them milled to keep the compression near stock, and then you'll be limited with your cam selection. You can still go kinda big, but nothing radical (under 230's duration without flycutting). It all really depends on what you're looking to do/gain. You can leave them unmilled, sacrifice the compression, go with a larger cam... the choices go on for days. At this point, the L92/L76 setup is pretty established, people making BIG numbers with smaller cams, turning in good (11.50's and less on the stock tires) times.

Keep in mind, if you do the LS3 heads, you've also got to add the L76 intake to your swap. Not too expensive, but another thing to consider.

 

If the cam is under 228 I would say yes. If you want to fly cut for P/V clearance then definitely. I have the 228 XER and a thinner gasket. Mine wouldnt fit without flycutting if I want the best compressin at 8.7 DCR. I would need another .7 of a point and that will require fly cutting. Its 15rwtq at peak and 20+ in the 3500 range. Thats substantial if you dont want a low rpm slug. I will be going this route when I get Cartek's ported L92 heads which will be milled another .030.

 

I know maximum lift has many variables to consider including and not limited to advancing/retarding the cam, duration ,and LSA...if anyone would like to advance an educated guess...with "30' off the LS3/L92 heads what do you feel would be the maximum lift without fly cutting the pistons on a cam with approx 215/230...LSA 117 to 118?

 

What are the particulars on the complete build and what are your expectations of the end result? Call or stop by, we can help.

 

do not want to walk in front of the original poster but I am in the same boat...that is I am very torn between doing AFR 205 with the new upcoming Weiand intake versus L92/L76 heads on an otherwise stock 2005 mn6..$ is not the issue but drivability is and for now I do not intend to do headers! My cam thought is to follow Chevrolet's lead and stick to a wider LSA cheater/stealth type cam such as the Thunder Racing CHEATR...I will wait to see the latest upcoming offerings from FAST versus the L76...only other consideration is maybe cai such as Breathless/Varam... I do not race or 1/4 but do like a 2-3-4 gear spanking every now and then...any thoughts are welcome and appreciated.

 

I have a 20005 Z51, currently with CAI, Headers and underdrive pulleys. I am torn between doing a Cam only install using a Comp Cams 224/228/581/588/114 or doing the same cam with the stock LS3 heads and intake, heads milled to 64CC of course. Does anyone have any thoughts on that package or final HP gains? I was thinking about 415hp cam only and 450ish with heads and intake......

Thanks

 

Before I put a 427 in my 05 Z51, I had my LS2 modded to 461rwhp/435rwtq using the ET 215 heads, the comp 224/228/581/588/114 cam, and the FAST 90 manifold. It was a daily driver. Smooth idle. Got 28mpg on the highway, and never had an issue. When I swaped in my new motor, I put My LS2 into my son's 2002 C5 with 50,000 miles on the motor and it's still going strong. I think those heads are great for LS2 motors. Yea, I know they cost more than L92 heads. But actually I think that L92 heads don't work as good as a good set of the standard heads for LS2's. For this reason; These L92 heads are designed to work on a bore of 4.065, not
4.00. Thus the large intake valve is just barely making it down the cylinder bore without touching the wall. This causes a major shrouding of the intake flow, and virturally negates the effect of a larger valve.
Where as the in ET heads, the valves seats are moved closer together increasing the path of the intake charge into the cylinders greatley increasing performance potential of the motor. It's true, that some tunners are making great HP numbers with these L92 heads,but it's at the cost of large duration cams. Driveability then becomes an issue. You need to think about what you want your car for. Some tunners will tell you they can make you 500rwhp in your LS2 with these L92 heads and make it idle smooth for a daily driver. It's a lie. The honest tunner woun't tell you that. Ask them if they can do it with a street duration cam in the 220's and see what they say. i've been there I know. Yes, it's also true that I have CNC ported L92 heads on my motor. But one must also know there on a motor with a bore of 4.068 and a stroke of 4.100. You have many options.

 

Thanks for the reply, you clearly have more knowledge of the internal parts than I do. Would you recommend then, just doing the cam with along with just porting my factory TB and intake? I know I'll still be a few ponies short of the LS3 stuff but I'll also have $2K more left in my pocket.

 

Before I did the ET heads, I had the cam and the FAST 90. BTW this is along the the standard headers etc. I made 425rwhp/405rwtq. I don't really know how it stacks up with the LS3's, but it ran very strong. At that point I was starting to over power the tires. Had to drive a little different. Couldn't just stab and expect to hook up. With what you have in mind, You could be in the 410rwhp/395rwtq approx. Many variables. That's ballpark. If you can afford it, The FAST 90 makes a big difference in torgue and power under the curve. which simply means the midrange torque which is where we spend most of our time driving. Topend power is also enhanced by the sheer fact that air flow is greatly increased with the FAST above 6000RPMS. Good luck.

 

Yes, I think your numbers are in line with what I was expecting. I think I am questioning weather or not the LS3 parts will be worth the money spent over just improving what I've got. Better put, is 40hp worth $2 grand..... I think I am the only one who can answer that at this point.