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What's the best way to check the headers and tails ?

Quote:

Originally Posted by Donziben (Post 4045629)

Thanks for the info!! I'll make sure and ask you if I have any questions when we tear into it. Next time you are up at LOTO stop by again and say hi. We are having a brand new marina built on the water, boat ramp, slips and storage, fuel dock, etc.,going to be very nice. We will be moving in spring, would be happy to help with whatever you need next time your up.

Don't hesitate to contact me if you need anything once you get into it.

I will certainly come check out the new setup the next time I'm in town. It sounds like it's going to be a nice setup. Can't wait to see it.
Eddie

Quote:

Originally Posted by AB69Z (Post 4046024)

What's the best way to check the headers and tails ?

You can send them to cmi. For $300 a set they will pressure check and polish.

Quote:

Originally Posted by AB69Z (Post 4046024)

What's the best way to check the headers and tails ?

There are 2 different ways to do it. The first way is to fill the header with water. We put a ball valve on the top water outlet fitting of the header and fill it up with water. We have the garden hose hooked up to the bottom of the header's distribution hose. Open the ball valve on top of the header until the header is full. Then, shut off the garden hose, close the ball valve, and then open the hose to put pressure to the header. If there are any leaks, water will come out.

The other way to do it is with air. Plug off the outlet fitting on top of the header. Hook up your air hose, with a regulator, to the distribution hose at the bottom of the header. Put about 25 psi of air pressure to the header and put the header in a tub of water. You can use anything large enough that the header will fit in, a tub, garbage can, ice chest, etc. Then just look for bubbles.
Eddie

Quote:

Originally Posted by TYPHOON (Post 4043088)

Just one other thing to be sure we are on the same page. Have some of these motors that have had issues been altered? Change the RPM, timing, ECM parameters and all engineering bets are off. I have seen first hand in the racing world when people play with the ECM, bump a little compression and call them stock that the failure rate is high. They were engineered to run exactly how they came out of the factory with the seal on them. ITS NOT WORTH THE EXTRA HP TO MESS WITH RELIABILITY on this motor.
Randy

Quote:

Originally Posted by Young Performance (Post 4045480)

The other thing you may consider if you want a little more power is doing Whipple's ecm tune. It really wakes them up in the mid-range. You will have to run 91 octane though. We have also done some with a little less timing that can run on 89 octane. It still wakes them up in the mid-range, just not as much.
Let me know if you have any more questions. I would be glad to answer them the best I can.
Eddie

We seem to have conflicting opinions here. :/

Quote:

Originally Posted by thirdchildhood (Post 4046468)

We seem to have conflicting opinions here. :/

But you only took part of my quote. The part you left out was me explaining that the valve springs, retainers and locks need to be replaced, the head gaskets and head bolts need to be replaced, the rocker arms need to be checked, etc., etc., etc. Personally, I would not do the Whipple upgrade, which turns more rpm, without changing the springs. I love Whipple's tune since it really wakes the 525's up. The 525 is a great engine, although it's nothing special. All of them have some issues, especially the pre 2005. Once those issues are handled, you have a great piece that can take almost anything you want to through at it.
Eddie

Quote:

Originally Posted by Young Performance (Post 4045480)

In your case, there are a few things that I would do. That will differ depending on the year of your engines. If they are pre 2005 engines, you will need to do a few more things. You should pull the heads and freshen them up. Change the springs, retainers, locks and seals. Go with 10* retainers and locks. This will open up your valve spring choices drastically. You will probably have to surface the heads. You should be able to get away with just scratching them and only removing about .003 or so. When the heads are apart, go ahead and lap all of the valves in. If they all lap in good, there is no reason to do a valve job. Once they are lapped in good, number them so they will go back in the same location when you assemble the heads for good. If they are pre 2005, you should change the head bolts from the stock GM bolts to ARP's. Also go with Cometic head gaskets instead of the stock composite gaskets. While the heads are off, have a very good look at the rocker arms. Check for any loose bearings in the trunnions.

Also, I would certainly check the headers and tailpipes for leaks, especially if its a pre 2005 engine. Those were the headers that were really known for leaking. We have seen several sets of tails leak as well.

Once all of that is done, you should be good to go. The other thing you may consider if you want a little more power is doing Whipple's ecm tune. It really wakes them up in the mid-range. You will have to run 91 octane though. We have also done some with a little less timing that can run on 89 octane. It still wakes them up in the mid-range, just not as much.

Let me know if you have any more questions. I would be glad to answer them the best I can.
Eddie

Here is my entire quote, just so there is no confusion.
Eddie

Thanks, Eddie. I didn't mean to take things out of context. I was just trying to highlight the ecm tune part. Some have told me to do it and others have said that it is not worth removing the safety margin for a bit more power. I'm leaving mine alone unless I redo the whole engine. I also like being able to burn the cheap gas. The whipple kit is tempting though. Maybe when my money tree blooms. :)

Let me know as soon as it starts to bloom, cause I'm camping out at your house :)

I'm not recommending against it, but I personally would at least change the springs before upping the rpms. I'm sure there are several that have done it with no problems. As a business, I'm going to error on the side of caution. I can't recommend something to someone that I have reservations about. I would feel responsible if there was an issue with something that I recommended.
Personally, I think Whipple's tune is awesome, and well worth the money. You just want to be sure that everything is ready for it.
Eddie

I am getting ready to svc and or do uppers to my 525's with 380 hrs. I think the uppers have already been done once trying to find that info out. My question is does Jesel not make a rocker for these heads?? My last few engines have been symmetrical port style "big chief" heads on my 762-800 inch pro mod drag car engines. All i ran was jesel or alan johnson on his heads. Why is nobody just putting jesel rockers on these motors when they do uppers???