Yeah ....that's right !!! Heard enough about them on this board to do just that !! Someone suggest to me what heads I should replace them with. I have a 1977 LM-1 350 in a 87 LG4 T/A ( Just rescently found this out. Color of engine and oil dip stick location should have informed me, but...Hey, i'm a Rookie !!) The motor is totally stock but I want to put in headers, performance cam, Performance intake, and will keep the same Q-Jet that's on there now. I do have to stay emissions legal, more towards the sniffer than the visual part. What kind of heads would you recommend for this setup ??? Would perfer to just go to a bone yard and yank off a pair for a good price. What would be a good cam also ?? Looking for low to mid range torque. Remember I have to stay emissions legal. Any advice or comments is appreciated. Thanks ! Fakeyankee

 

Theres nothing really wrong with 993 or 882 heads, they were not the cause of the smog 350's being ****. It was a combination of pure crap parts ( cam, pistons, intake, emissions equipment) that made the motors crap. If you port them up and install dome pistons or a SC you will have a nice cheap setup.

 

Having had many, many of those cars back in the 70s when they were new or nearly so, and having swapped the smogger heads off of them and experienced the results, I would have to disagree with that. I've changed out entirely too many of them over the years.

Almost any heads will make the engine run better than 882, 993, 624, etc. The first thing you need to look for are ones with a smaller combustion chamber, realtively large valves, and good-flowing ports; the old double-hump heads with bolt holes only, or L98 (350 TPI) heads, are the best ones. The double-humps are getting rare but you can get L98 ones off the classifieds on this site quite easily. Look for casting number 083 for L98 heads; or 186, 492, 041, 292 for double-humps. DO NOT get the really old double-humps without accessory bolt holes.

Some people will even tell you to get certain 305 heads (416 casting in particular) and put larger valves in them and port them. I can't verify that, but those heads are bound to be better than the smogger turds, if for no other reason than that the chambers are 58cc instead of 76cc, which will at least raise your compression.

I'd recommend a ZZ4 intake, a Comp XE262 cam along with the srpings that Comp recommends, a set of better rockers that aren't stamped steel or any kind of aluminum, and some kind of chassis-specific headers and cat and cat-back exhaust for something like a 350 TPI application. DO NOT get any exhaust parts that are compatible with your LG4 stuff!!! That means every piece from the heads to the street, all at once, as an assembly.

 

RB.....why do you say not to get exhaust components that match up to the LG4 ( For smog hookup reasons ) ??? Eventhough I have the ol LM1, the prior owner pulled out the old LG4 less the stock exhaust manifolds, and dropped in the 350 and bolted them back on. So, wouldn't the headers ( Edelbrock TES for LG4 ) hook right up to my LM1 ??? I understand that the Hooker 2055's would work but I would have to rework the tubing. If it's a difficult task and PITA....I'd just asoon not !! Fill me in. BTW...Thanks for the head info......will write it down in my black book and take it to the bone yard for reference. Thanks ! Fakeyankee

 

.....or did you mean complete exhaust kits ???

 

Yes, the headers for LG4 will bolt right up to the motor. But.... If ANYTHING of the LG4 exhaust is left, specifically the Y-pipe or the I-pipe, they are tiny little drinking-straw-sized things; and headers or no, they will choke the motor. Problem is, if you get headers for the LG4, they will have the little tiny Y-pipe so that they'll bolt to the LG4 exhaust; if you get a cat-back for LG4, it will have to bolt to the little tiny pellet-bed cat; and either of those will work againt the purpose of all this, which is to eliminate restrictions, not preserve them. The ones for a 350 TPI are much larger, and cost the same.

The smog pump hookups are not really a performance issue. That system costs very, very little HP. Personally I don't find it particularly worthwhile to just strip stuff out of the engine bay, as that almost always has unintended and unforeseen consequences, whether the person doing it realizes it right then or not; if all of that is still intact, I'd recommend getting headers that accommodate it. You never know whether you might move to California (like I did) and if you do, you'll be needing it.

 

OK.....But are the emissions hook up the same for TPI as for LG4 ?? Or will I have to "Rigg" it up to match ?? As for the heads you recommended, say the L98's...... If I got them from the junkyard, would they bolt up to the stock Intake manifold that my LM1 350 now has, or would I have to get that too ??? Mind you I will be getting my performance parts piece by piece. I figured the first Item would be headers. What would you get next or in what order would you recommend installing the modifications ??? BTW....here in Massachusetts we also have the emissions tests, so I will not be taking off any of the equipment. I just want to make sure that any performace parts that I add will not hinder the smog sniffer tests. If anything, I would hope to improve the emission standards more than what I have now. Then again...hope i'm not asking for too much !!!! Fakeyankee

 

The exhaust is all the same. About the worst you might have to do is go to Auto Zone and look through their pre-formed heater hoses, and find one with a 90° to make a hose out of.

The L98 heads will not quite bolt up to the LM1 intake; the angle of the center 2 bolts on each side is different. You can, however, easily alter the bolt holes in the intake to fit those heads.

None of what I am suggesting would hinder your ability to pass emissions tests; not even in California.

I believe I would get the whole exhaust first, as a chunk; then save up and collect parts, and do the heads, cam & intake all at once.

 

Worked for me...

 

OK Guys........... so get the whole exhaust system plugged in first, Then do the intake, cam, and heads, all in one batch, or can I still do Intake and cam ( and replace the timing gear and sprockets, as well as water pump, since i'm there already ) Then last but not least, put on some descent heads to top it all off ???? This is what I gather from you guys...........Would this be a good way to go , meaning in that order ???? Can't do everything at once since i'm raising 4- teenage sons who think the Jap rides are the best way to go. I want to "Blow them out of the water !!" When I get this setup all done. I still believe in good old American Iron ! Would love to put them in thier place !!! What do you guys think ???? Thanks !! Fakeyankee.

 

How come noone mentioned Vortec heads? They flow good right off the bat and are around $500 for a pair of em brand spankin new. All you need is a diffrent intake and intake gaskets for them to work on a older 350. As for stock heads the 993's are fairly good the 882's and 624's are a thinner casting and thus will crack and warp alot easier. If you go with a stock head put some 2.02 and 1.60 valves in it and also bowl hawg the ports that'll make it flow fairly decent.

 

I like that idea Caddibird...especially the price. But are they or can they be made emissions legal ?? Will all my smog stuff work with that kind of intake ??? Thanks !

 

To tell you the truth I don't know if they make a emissions intake for it but check out www.edelbrock.com if they make one their site would show it. If they don't you might just might be able to pass the smog test without the emissions gear but I wouldn't want to spend $700(heads + intake) to find out If they don't make one for it I'd try to find some casting # 993 heads and let a machine shop work em over with bigger valves and all the other goodies. I don't know what the machine shops near you charge but to completely rebuild a set of heads it's around 500 or 600 bucks. Like I said earlier about the only bad thing with the 882 and 624 is their thin and crack fairily easily.