Okay, this topic is mainly for those who always put down or the lack of trust they have in our stock bottom ends.

Who has pushed it to the limit, or beyond using a power adder?

I really want to know from the boosted stand point (Big single, or twin turbo) but nitrous adventures I would also like to know.

If you could, stat your mods and your numbers if you have them.

A friend of mine on a stock 85 305 TBI ran a 125 shot for as long as I can remember, still running it, it has higher miles and does blow a little oil but i think its more due to the miles rather then nitrous.

I'm not boosted but I can give you a little experience from my standpoint. I have a big cam, big heads, MiniRam, longtubes, etc. I push the motor to 6500rpms consistently. I'm probably close to 475hp at the crank. Haven't had any problems yet. I know that boosted is a different story entirely. But, I just thought that I would pass along my experience regarding just pushing the power through a stock L98 bottom end. The motor has never been out of the car.

Tim

I've pushed my stock short block to the edge and over it. It had a 163K on the clock. The stock bottom end didn't fail but the same cant be said of the stock slugs. For pics go here: BROKEN MOTOR The new motor will push the limits of the stock crank as I'm running forged pistons and forged rods. The motor goes together with a set of ported and polished L98 vette heads running 2.00 intake and 1.56 exhaust valves. Also a ported LTR setup and a 2 stage 150 shot for a total of 300hp in addition to what the motor makes NA. The custom J&E pistons and the small 59 cc ports on the vette heads makes for static compression ratio of 11.1 and coupled with the LT4 HOTcam I'm running makes for a very pump gas unfriendly dynamic compression ratio of 9.2 (Luckily I live and race at 5800 ft)

HTH
CB

Looks like you guys are running 350's.

Do you think the 305 botttom end is the same as far as duty is concerned?

Thanks.

I don't see why. They are essentially the same design...and the 305 rotating assembly should be lighter, given the smaller bore and the lighter piston.

Finally I am getting some usefull answers here!

I currently have been asking the same question on several posts and have got no answer.

I have been advised by several people that my current 343 RWHP/ 390 at flywheel is the max I should push my bottom end.

But I see posts of others running much more HP nitrous with no posted problems??

So I am looking at TRAXION and his mods. If he can run his 475 HP, I figure I can push for another 50 HP.

I'll probably call ATI this week to see what the next up grade is for the blower pulley.

May look into alky/water though to make sure I get no detonation.

Thanks.

As long as your not running it lean I don't think 50 hp would create too big of a problem. The main concern I'd have with going with more boost is the higher cylinder pressures and stock cast pistons..That was my weak link.

HTH
CB

I have a 90 Iroc, stock bottm end, 5.7, 103k miles, it has a vortech r-trim, mini-ram, zz-9 9cam, brodix heads. Runs solid, and I used to drive it daily until gas got to be to much aroud here so I got a 4cly truck to fix that. I keep wanting to build a new bottom end but this one is still going.

The main concern I'd have with going with more boost is the higher cylinder pressures and stock cast pistons..That was my weak link.

That is an interesting comment.

One solution to get that extra 30 + HP would be to add better flowing heads. Then I could increase the HP without an increase in cylinder pressure.

If your refering to adding better flowing heads to your combo. Yes its true you'll see less "boost" on your gauge because of less restriction (the air can't "stack" up as readily as before). But you will still be packing more air into the chambers than before and that is where I feel the stock pistons will fold. But hey I could be wrong........

CB

Actually, Once you remove the heads I've been told that you can remove the pistons with the engine still in.

Does this sound right?

I dont think you could get the pan off

How would that go? You'd have to drop the oil pan....and then you'd need to put the car on a lift so you could remove the pistons and push them out the top....

you would nearly have to completely remove the engine to get it high enough to get the pan off, then get undernieth and remove the rod caps and nuts and push the pistons out the top with the head off. If you crazily installed new pistons on the rods it wouldnt even be close to ballanced the only chev Ive seen this can even come close to being done on is some big old chev 4x4's and the balance problem still applys of course.

Yea. Don't know why someone said it could be done.

Looks like it would just cause more problems.

I'm just going to run the bottom end as is.

Figure with 73,000 miles, it should have a few years to go.

Start saving now for parts!

Amen Brother, Amen

Run it till it breaks and then build it stronger