I have an 89 Iroc with a 5.7. The owner before me had the engine replaced with a reman. When they replaced the motor they put hooker headers on it
and really did a rig job doing the rest of the exhaust. So I purchased a set of edlebrock headers and y-pipe. When I took off the driver side header bolts
coolant started leaking from one of the bolt holes. I realize a water jacket must be cracked. Has anyone run across this before.
My next question is what type of head should I replace them with.
It is a stock block with an airfoil, MSD coil and headers no other mods yet.
I ran two passes with it and the best time was a 14.3 at 98mph.
Im looking to make 12.5 on the 1/4 so I can start racing
at the track for fun.
One last question, Is any body familar with the street eliminater class (NHRA)
Thanks
Keith

 

The two lower, outer head bolts go into the water jackets on SBCs. If those are the ones, it's normal. Put some sealer on the bolts when you replace them.

 

It was the one on the driver side 2nd bolt hole from the firewall. How can I find out if the bolt hole does indeed go into the water jacket.
Thanks
Keith

 

No exh man bolts on the SBC go into water. The water jackets are behind them, but they all have bosses behind them, and the holes are blind. Or at least, they were, when they left the factory.

If you have water leaking out any of them, then either they're cracked, or have been drilled out, maybe for Heli-Coils or something. A little too enthusiastically it would seem.

Not much you can do about it now, except put some suitable sealer ont he bolt threads. I'd suggest the Permatex "automotive pipe thread sealer with Teflon".

As far as head bolts (an ALTOGETHER other matter besides header bolts), all 17 on each head go DIRECTLY into the water jackets of the block.

Yerbasic typical reman motor will have TBI heads on it, those being the most commonly available ones. They are some serious crap for performance. I assume that's somewhat of an issue to you? If so, get their casting number, and prepare yourself to replace them if they turn out to be TBI swirlies. Not worth buying a tube of sealer to rig a cure for a leak IMO.

 

Sorry, I read "head bolt" when you said "header bolt" none of the header/exhaust bolt should go into the water jacket.

 

When I went from 3/4" header bolts to 1" on my World heads, I poked through the back of one into water. I tried filling the back end with JB Weld, not exactly easy when the engine is installed in the car. I ended up putting silicone on the the threads of that bolt. It hasn't leaked again in over 2 years.

 

bump

 

What did you bump for?

For NHRA class info, try the Drag Racing forum.

For a 12.5 second ET, you're going to need new heads, a large cam, better headers, and a custom chip.

 

...which means plenty of money.