In process of getting ready to order a LE2 package from Lloyd Elliot.
Lotsa advise. Expecting to produce around 500 hp . Will the
Crank, pistons, rods etc. hold up, or barely holdup, and if the advise
is to upgrade is it sufficient to change pistons (forged) and rods only.
I really do not want to get into a stroker setup.




95 Z28 LT1 A4: Red w/Black Ttop; 3:83, full race susp. Holley 52mm
and too much to list.

 

Well I have always heard the bottom end was good for 500HP. IMO you are good to go but don't expect to get a long life out of your motor before something in the bottom end decides to go boom.

 

Let me give you the lowdown on second-hand information I've gleaned from this board. The parts in your stock motor will be perfectly fine for an le2 set up, power-wise. The problem you're going to run into is with RPM. AFAIK, the weak point is the stock rod bolts. They stretch at high RPM, the big end of the rod distorts, and viola, a spun rod bearing. Wheter or not this is actually the true, I don't know; however, out of the 20 different explanations I've heard over the past few years, this is the one that seems most plausible.

Ian

 

The theory for spinning rods on a cam swap on stock bottom end, especially with high mileage I heard was due to worn front cam bearing due to water pump/opti load casuing oil starvation at the rod bearings at high rpms. The stretching of stock rod bolts however sounds plausable too, I've never heard of that one. So theoretically if you replaced say the front cam bearing and rod bolts, you shouldn't have a problem, am I correct?

 

I should have my h/c and intake back from Lloyd mid May and installed late May. I will be running a 100-150 shot of the lauging gas through it. I dont expect it to last for a long time with the gas.

 

From what I've seen its a hit or miss kinda deal. I went 2 years with my heads and cam setup shifting at ~6800rpm on the stock bottom end. At 80K miles I spun a rod bearing. Some have had engine failures with fewer miles. My buddy put a cam in his LT1 with over 100K miles, raced it hard for nearly 2 years then threw a 7lb Vortech blower on the car over a years ago. Its now got 125K miles and still running strong. Bolt the heads and cam on and keep your fingers crossed

 

I have no clue how that car ever held together?!

-Dustin-

 

If your on the stock bottom end I'de go with the LE1.5 cam, I'm 99% sure thats whats in my car and it revs to 6500+ fine.

 

It was magic fairy dust

 

You know "Cantonracer"...that is the magic.

 

So your the "magic" man. Throw some my way, I want high 11s before the end of the year. Thanks in advance, Rick.

 

I've seen the stock bottom ends last for quite awhile, just dont throw RPMs at it. If you can get a custom grind made to shift at 6300 or so you shouldnt have any problems for a long, long time imo.

 

I agree 100%........RPM's seem to be what takes the bearings out on the stock bottom ends most often.....not the power level nesessarily............I've been running a 140 Rear Wheel HP shot since Aug of 98(about 200 HP at the crank).........in late "05 I did the LE2 heads with the LE 1.5 cam and ALL the supporting mods......since then I've been running a 125 RWHP shot of nitrous.....and now (as of a few months ago) im running a 175 RWHP shot.........still no issues after all these years shifting at 6300-6400 RPM.......cylinder compression is still nearly perfect(leakdown test good as well)....and I pulled a couple main caps off when the pan was off and the bearing wear is normal... nothing out of the ordinary.......And on the other hand, I've seen people with naturally aspirated engines(with WAY less HP that im running) put in cams that pull "PAST" 6500, and then in no time they have bearing issues......I would personally stay with a cam (like the LE 1.5)that won't "need" to go above 6400-6500 RPM max ....untill you plan on a FULL engine build with forged internals.......Just my 2 cents.............Joe

 

Listen to these guys it's RPM thats the killer

 

Not to hijack the thread but, Bret when I got my LE2 cam from you, I told you I wanted to spin 6500 on stock bottom end and you thought the LE2 cam would be fine. is that not the case anymore? or is there more to it?

I regularly spin to 6500-6600 and feel that anything smaller than the LE2 would be a step in the wrong direction. Ive had the LE2.2 cam in my car for over a year now and havent had any problems with the rods!? does it matter if you have the PM rods or the standard rods?