sbf

Has anybody custom made there own coolant tubes that don't go under the intake I'm using a fast 92mm.pictures would really help

02BlkZ28

Go to chevy & get you some rear coolant tube block offs.

Sean At CBM

Plug all 4 corners off. Part # 12602540 for the plugs

WS.SIX

iTrader: (3)

I wouldn't block them off.

I purchased a steam vent kit from a non-sponsor on eBay that looks very nice. It will be seen during the completion of my upcoming build. You can find them on eBay if you search for "ls1 steam vent kit".

Another option is the kurt urban steam vent kit which is nice as well but I didn't want a box sitting on my intake.

02BlkZ28

Whats wrong with blocking them off?

WS.SIX

iTrader: (3)

Higher temperatures in the rear of the cylinder heads... which happen to be cylinders 7 and 8. The ones that like to go

02BlkZ28

So question i have then.. Could that cause problems? I havebt tore my motor down yet. But i know something is hurt. I lost alot of power & its popping out the exhaust when shift. I thought i hurt i spring or a lifter or a valve. I got alot more noise in the valve train than normal. Sure hope i didnt burn up a piston or something

WS.SIX

iTrader: (3)

Blocking them all off basically traps air/steam/reduces coolant flow at the head so it is possible that you could have detonated. Pop your valve covers and start poking around and dont run it until you find the cause. Otherwise you'll probably end up doing a build thread like me!

02BlkZ28

Ive pulled covers off found nothing visual like bent push rods or broken springs. So im about to pull the motor & tear it down. I did miss a gear a few months back, so that could have been the cause.

2000PewterT/A

Never ever block off the steam ports, the cylinder temps in the back go way to high and can cause internal damage.

conan

iTrader: (5)

Here's what I'm doing with my steam ports this time around... The rear crossover tube is from a cadillac, GM part #12605716. The front cross over tube is from the ls6. I dont have any finished pics but I'm using the black braided fuel hose and have the 2 lines connected together with a stainless 1/4" Y fitting where it plumbs into the radiator.

Here's the rear cadillac crossover...





Here in the green square is the front ls6 crossover...

silverLSWON

iTrader: (16)

exactly what i did...DO NOT BLOCK THEM OFF!!!...i just blew 2 motors up recently (ringland on cyl 7). the rear crossover in these pics are off an l92 6.2 motor on escalades and denalis. cheap insurance if you ask me..

Robert02

iTrader: (2)

Yep I chipped the top edge of #7 in my LS1 and it caused piston rock witch cracked my cylinder wall and let the coolant flow. Now building a 416. Cadilac vent tube looks better than using another LS1 tube back there.

Robert02

iTrader: (2)

02BLKZ28 could have a bent valve,push rod or weak spring do a compression test to find the weak cylinder.

one fast zo6

iTrader: (490)

very nice

02BlkZ28

Wow i sure hope i didnt hurt a piston or a cylinder wall. I just built this all forged 383 =\ just dropped about 10k in this motor.. Im hoping its just a valve train issue. Like weak spring or hurt lifters from missing a gear.

L_Brown

Buy these


and do this

FAD2BLK93

Yes...do that! Dont block them off. They are there for a real good reason. They work.

Sean At CBM

If it is wrong to block off the coolant passages, then why does GM supply most of the production engines with the rears blocked off? Once you bleed the air out, it stays out. We have plenty of engines out there to prove that blocking off all 4 is fine. And these engines are in off road application where the chance of getting an air pocket would be way greater then a car.

M6 Swap

iTrader: (1)

My 5.3 came with the rears blocked off