: Are All Xlr's The New Style Closed Deck?



VIPERRACING
05-07-08, 02:51 AM
Just wondering about the xlr motors and how strong they are. Im looking at an 04" and was thinking about adding some kind of forced induction or nitrous if it can handle it. Thanks for any info.

Jesda
05-07-08, 02:55 AM
As you know, the XLR-V is supercharged but displacement has been reduced to 4.4L. See previous threads for explanations why.

As is, the RWD N* V8s are 80% new and generally trouble-free.

AJxtcman
05-07-08, 07:16 AM
Just wondering about the xlr motors and how strong they are. Im looking at an 04" and was thinking about adding some kind of forced induction or nitrous if it can handle it. Thanks for any info.

I work at a large Cadillac dealer. We have only seen 2 or three 2000 to 2003 FWD Northstar head gasket Failures!!!!! :mad2:

We have not seen a 2004 FWD or RWD Northstar head gasket Failure! :yup:

No they are not closed decks, but they use LSx head bolt threads.

I really hate having to say that. Everyone seem to think that the LSx engine is better. I don't think so!

In 2007 we saw more head gasket failures in 2002 to 2005 Escalade's than 2000 to 2007 FWD Northstar''s :cookoo: I personally know of even more LSx head gasket failure in GMC and Chevy's. A good friend of mine has a 2005 GMC 4.8L lost a head gasket at 36,100 miles and we had a 2003 5.3L Chevy in the shop that head gaskets.

Do the math 1 FWD Northstar, 2 Escalade's + 1 GMC + 1 Chevy = 4 to 1
Yeah 4 head gasket failures that I know of in the Milwaukee area. WOW that is going to put the General under. Oh yeah we are talking about that 1 Northstar not the 4 LSx engines

NHRATA01
05-07-08, 10:37 PM
Yeah but look at the volumes of LS-based motors vs. Northstars out there. Since all of the truck V8s are LS motors, thats about 700,000 units per year alone from the Silverado/Sierra. Thats not even counting passanger cars and SUVs. Total N* production is probably a tenth of that at most. So by averages, you're going to see more LSx's come into a given shop.

LSx's really are not prone to HG issues, unless something else is wrong with the motor that took out the HG. Back in the early days you could get up to about the 550-600 rwhp range with lots of spray or boost, and sometimes you'd find the odd person had an issue lifting the heads with the stock TTY bolts and older pre-MLS gaskets. ARP studs are good enough to take them well past 1000hp, and the new 6 bolt per cylinder aftermarket blocks go way past that.

The N* is a nice motor, especially for a luxury car, but it can't take anywhere near the beating the LSx's can. I've seen a car where they threw on a T88 snail on a totally bone stock LS1, kept upping the boost trying to blow it up and with good fuel and tune they pushed to about 770 at the wheels and gave up, the thing would not let go. Someone else tried to kill one with spray, got up to 2 stages and 400hp of spray alone before he cracked a piston and lost it. You'll never come close to that kind of power and keep a stock Northstar together.

VIPERRACING
05-08-08, 12:37 AM
I was only thinking about adding 100-150 shot if the motor is the new style closed deck. Ill try to do a search to se if it is. Thanks to everyone that replied.