I recently heard that LG4 heads flow better than the heads that came on LO3 engines, is this true? I am interested in doing this because the salvage yards are littered with these engines in my area, I could get a set cheap, like $50. I'm not to bad at porting so they probably be a little smoothed inside. Plus I would not have mod my CFI intake to fit the later style heads. So here's my questions. Will this lower my compression down to the LG4s wimpy 8.4:1? I don't really want to have any machine work done. My LO3 is all stock right now. Did any LG4s have centerbolt valvecovers? Not a big deal though. What condition should I expect the valveguides to be in? My car has a 160 thou on the motor and runs great, are the carb engines less durable? I am planning on swapping in an LT1 cam. Here was my idea, since I have swap valvesprings anyway, I thought I would get a set of these heads and mildly port them, install new valveseals and springs, and add them when I do my big TBI to CFI swap. I not looking to outflow Torquers or any other good heads, I just want something a little better than stock ( for now ) since I'm tearing into the motor anyway. What do you guys think?

 

If you can find an 87 or even 88 LG4, then yes they are centerbolt valve covers, and they use the 305 TPI heads! The earlier perimeter bolt heads I do not know how much better they are, but they used the same heads for both LG4's and L69's.
I know the casting number for the 305 TPI heads is 14101081. I think the carb heads is xxxxx441 or something like that. They all have 58cc combustion chambers, so you wont lose any compression.

Are you seriously considering switching from TBI to cross-fire injection? You realize thats an even bigger step backwards than what you have now?

 

Why are you going to a CFI setup? I don't have any experience with CFI so what are the benifits? From what I've read it seems like it would be a lot more complicated than TBI. What would the benifit be over say a Holley 670cfm TB with a good manifold?

 

Let me clarify on my intake swap, I'm not swapping stock TBI for stock CFI, I know that is stupid. I swapping in a fully ported CFI intake with 2" TBs run by TBI computer ( it can be done, CFI ECMs suck ). I did a post about this a while back, and once I explained it, the feedback was mostly positive. So the centerbolt LG4s have TPI heads,wow, but they have the latter intake bolt angles to right? Not a big problem if there TPI heads. So would any LG4 heads be a step up, like I said, I'd pocket port them since I already have stuff to work on the intake. Like I said, their a dime a dozen around here. Are these heads prone to cracking?

 

CFI can work well, just don't expect wonders by throwing an all stock CFI setup on your car. Fully ported, I'd say, but can't prove for sure, that it is better than the Edlebrock TBI intake, they are not to expensive if you can find them, less than a new aftermarket intake, if you don't mind spending some time on them they aren't a bad option, plus they look cool. However, I doubt they are better than say a single-plane with a big aftermarket TB, but that won't fit under a stock hood and it will lighten your wallet a ton.

 

Oh, I forgot to mention, 1MEANRS CFI is TBI, it just uses two smaller throttle bodies on an aluminum cross ram manifold. People avoid CFI like the plague because they really were lousy from the factory, but they can work.

 

Uhhhhhh an '88 LG4??? that must be a reallly rare engine, considering the L03 replaced the LG4 in 88. The only centerbolt LG4s are the '87s.

Oh yeah and RSRagtop I was just looking through my dad's magazines and he has a '86 Hot Rod where they take a stock '84 Vette and it ran 15.0 in the 1/4 then they threw two 2" TBIs on it and some headers and then it ran 14.2, with everything else stock.

 

Imagine what that car would have run with a ported intake . Anyway back to the heads, should I beware of any problems with junkyard heads? Are these heads prone to cracking? What condition should I expect the valve seats and guides to be in. My original heads are still good after 160 thou' on 'em. Read a lot of posts about LG4s lasting for 250,000 miles without lifting a valvecover. I goin' to do this swap if I can find a set of heads that don't need machine work.

 

LG4's still came in '88 G-bodies, the last year for both.

And yes, of course, all the 87+ heads have the changed center two intake bolt holes. Except the L98 Corvette heads, but we're not talking about those, just the stock f-body heads.

 

the lg4 was an option in 88 but im sure its pretty rare...my 88 is a lo3 which is alittle better than a lg4...not by much tho

 

If you're going to all that trouble on a set of used heads why not use a set of 350 heads and have them milled to keep your compression up. Most 350 heads have the larger valves so they flow better than 305 heads. Just thought I'd throw that in for conversation. What do you think?

Steve

 

I would use 350 heads, but I don't want to have to mill them ( more $ ). Everybody keeps saying I'm going to all this extra trouble, but its not to hard to swap heads when the engine is stripped down to the longblock anyway. Plus I haven't seen any 350 F-bodies in the junyard and all the trucks have been run to death. I see clean Camaros all the time that were wrecked and came to the yard to soon IMO.

 

Don't forget that there were a lot more cars with 350 in them than just the camaro. Caprices, vans as well as trucks and you can go back into the seventies if need be. Call some of the local machine shops they may have a set of heads that they need to get rid of, you can usually pick these up pretty cheap too.

Steve

 

Dont even bother with that much hassle trying to put 350 heads on a 305. Its not worth the money and the larger valves end up being shrouded anyway, which kills any benefit they'd give.

 

Well after thinking about it, the 350 heads have 72cc combustion chambers witch would be pretty hard to machine down to an acceptable level. As far as the valves being shrouded I don't think that would be a problem. Most aftermarket heads and vortec heads as well as stock 462 and 882 heads have 1.94" intake valves, there seems to be a lot of people using the vortec and WP heads on their 305's and they haven't had any problems with shrouded valves. It would be a extra lot of work though to make the 462 or 882 heads work properly.

Steve