I'm going to need a valve job - sizable puff of smoke on start up everytime unless I shut it off and within a minute start it again. It clears right up, though, and the thing has passed emissions twice since I've owned it. It flies through emissions, actually. My question is about the heads that are most likely in it. I have no reason to think they're not the originals. I did a quick search in here about heads but didn't find anything really. I'm curious about the combustion chamber volume. Can you point me in the right direction?

Thanks in advance

 

Valve seals are a common cause of the issue you're having. It may not need a whole valve valve job(although it never hurts to freshen them up)

heres a link that should help you figure out combustion chamber volume for your specific heads
Combustion chamber volume list

 

Thanks, and I know you're right. I hadn't thought about just valve seals for awhile. I've done so many other things to it since I got it that I kind of let that thought slip. Plus the engine runs so good I'm sure it's worth it to give hard thought to doing that first rather than either entirely rebuild the heads, or replace them with new.
Thanks again chevyriders
Anyone call you "CR?"

 

In 1988, I believe that a K5 Blazer should have come with the RPO code L05 5.7L v8 with throttle body injection (TBI). If that is the engine that is currently in your truck, the heads should have '14102193' cast into the lower surface under the valve cover. These heads have 64cc combustion chambers and were the predecessor to the Vortec heads used in later engines. Not a great head for performance as they did not flow well.

 

swartlkk

Thanks for the response. Yes, my K5 has TBI, and that is good info you gave re: my newb thread. FWIW I am much more concerned with low end torque and mileage than hp. And $$. If valve seals fix the problem I'd be stoked. If the heads need a valve job/rebuild, that's why I was asking about the chamber volume. My suspicion is it'd be more cost effective, and a better performer, to just get new, low cost, current technology 'assembled' heads, like Summit pn SUM-152123, than having my existing heads rebuilt. I would want to keep my motor low-octane friendly.

I have a '70 Camaro SS project for the other stuff ...

 

The cylinder head shop.com

I bought a set completely redone and shipped for the price of ONE of your summit heads.

If you are keeping the tbi check out TBIchips.com and educate yourself to determine what is possible and set your goal.

 

Thanks for the tip. If the quality is there, and I assume it is since you bought a set and recommended them, $350 for completely rebuilt/remanufactured heads is a screaming deal. Especially if it includes shipping.

 

I only recommended them for a stock replacement as it's cheaper than having your heads gone through. If your looking into performance build you really need to look elsewhere and be prepared to spend lots more.

Though now-a-days I am more likely to advise a simple ls style swap over rebuilding an archaic smallblock if you want both more performance and drive-ability. Swapping from tbi to ls is so much easiler than swapping from a carb that it doesn't make much sense to do anything else unless you aren't doing the swap yourself. Its only a small fraction more money than rebuilding and its way better in every way.

 

I agree.
At this point I'm not looking for more power, just maximizing the low end torque and mileage. I'm working on making it reliable transportation and the TBI actually works great. I haven't driven it enough to calculate the mileage. It has 3.42 gears and 33x12.50s, so I'll have to do some math to figure out how accurate the speedo is. I did just have the 700R4 rebuilt and a new speedo cable installed.
I would love to convert to an LS. I have a 2004 2wd Silverado extra cab 1500 with a 4.8L that's been a fantastic vehicle with a fantastic engine. I would love to swap that into the Blazer, but I need to make that thing go away. I can't keep everything, and I like the Blazer more than the pickup, so ... priorities. The checkbook is not deep. I have an HOA so I can't be doing swaps and rebuilds in the driveway, sadly.
If I was in a position to do a major upgrade, I would definitely be after an LQ4/LQ9. Hopefully down the road ... For now, try to make what I have healthy.
Thanks again, goatman