So I was playin around with my DIgital Camera today and decided to take a few comparison pics between my 187 L03 heads, 1983 LG4 heads and World Products 305 S/R Torquers.

Ports:


The ports are pretty ragged on these LG4s. Even though the metal is rough from time, it's ragged from the factory.



L03=Can u see the intake valves? Thats because theres a bunch of iron in front of them. YOu cant really see it because of the darkness but they're pretty shrouded.



(LG4-L03-World)The L03 ports are huge compared to the other heads and the pushrod clearances are pretty smooth lookin and the ports are very clean around the edges from the factory. Too bad the valves are so shrouded.

Chambers:


The spark plugs on the LG4 are recessed slightly and aimed in the general direction of the intake valve. Not really that great.



The L03 spark plugs are out near the exhaust valve; seems like a good design.



The Worlds have a good half moon chamber with the spark plug sittin right at the intake valve. Looks pretty good.



I think the L03 heads are a great design and GM really screwed up putting the iron in front of the valves and the cast in swirls (which I didnt show) I think these heads would flow awesome if those 2 bottlenecks were elimininated.

 

you getting ready to install the world product heads? if i decide to keep the 305 ill probably put a set on the world products on this summer but im not sure what im gonna do yet. im considering a cam swap, intake, and heads instead of a 350...seems like it would be alittle less stressful and with a small shot of n2o probably faster....(im talking 330hp crate motor vs modded 305...not saying a 305 like that is faster than any 350 please no flames) i figure for the price of a new motor i could get the heads and work on ALOT of suspension and handling mods...this car isnt a race car and somehow im finally starting to calm down so i may stay with the 305...only time will tell...anyways when you get the new heads on let us now what kind of gains you see

 

Oh yeah I'm putting on the World Product S/R Torquers and the engine should be all back together by about wednesday if all goes well. We'll see how she does then.

 

I was just hopin to show a few people who are thinkin of swappin to other types of heads what;s really goin on inside

 

I have some pictures of my new AFR190 heads:
http://jobyteknik.homeip.net/corvette/afr190/afr190.htm

And a comparison to my stock L83 heads:
http://jobyteknik.homeip.net/corvette/afr190/afr190.htm


AFR190:


L83:

 

Thanks JoBy for those pics...those L83 heads look like they're a decent design but look at those AFR's chambers! they look sweet and they look like they flow tons

 

The L03 heads supposedly have a fastburn design right? Is that why the spark plugs sits so far into the combustion chamber?

 

I had an LO3 and a 081 casting 305 TPI head side by side last month and the combustion chambers are the same from what I could tell. Just different ports.

 

Yeah the L03s have the larger intake ports but that piece of metal in front of the valve where the TPI version has no metal in front of the valve, correct?

 

so, this is making me think that if cleaned up and worked on, that the lo3 heads could be made to be ok?

those ports are pretty big, probably not too much velocity going on there.

But if you unshroud the valves and get rid of the swirl they wouldnt be too bad would they?

so for the orig question. can you do something with the l03 heads to make them good ones?

 

See I'm wondering that too if the L03 heads can be made to perform. I have the Worlds so theres no plans for the near future for the "187" heads, but who knows, down the road maybe I will get them flowbench tested before and after.

 

But how will they run? I've got the AFR 210s on my 391 stroker and they're great but I'd about lost hope for my RS's small bore 305. Tell me they help...please.

 

the best route to go for a 305 head in my opinion would be porting/polishing and putting 1.94 valves in the stock heads, just pick some iron ones that have a good reputation. If you're going to buy new heads there's better places to spend the coin...

TP

 

The only problem with that route it seems is you can only take a stock head so far in modifying.

 

Yeah the L03s have the larger intake ports but that piece of metal in front of the valve where the TPI version has no metal in front of the valve, correct?

Thats what I'm wondering now. Cause I was planning on, when/if I get some $$ to do a budget rebuild, putting a set of H.O. heads on. IF the HO ports are the size of they LO3 heads without the metal in the way, they're probably not too bad. I mean they won't be anywhere near as good as aftermarket ones, but you have to keep in mind I'm trying to spend as little $$ as possible.

I haven't got much feedback on it yet, but my idea is rebuild either mine or another 305 roller shortblock, LT1 cam, centerbolt HO heads, and an edelbrock TBI intake. Nice simple setup, and shoudln't cost much. If I can hit ~230-240 HP with that (tuning required I know) I'd be happy. This will be after I get headers and stuff of course. Plus then I can honestly tell people "its just a TBI 305, and the only aftermarket thing is the intake." Which would be true, since the cam/heads are production GM parts... for other cars.

 

Yeah thats pretty much it, except the L03s seem to have more elongated ports over the TPI heads (thats what I assume you are referring to as H.O.)

Yeah really they arent going to be as good as aftermarket ones, but on a budget, they are great. I think the problem with the L03 heads is that no ones knows actually what they look like on the inside. We just hear all the bad stuff about them, but most people just go by other peoples words and havent actually taken them off and compared them or analysed them. Sure they wont flow well with the cast in swirl at the intake valve, or the metal shroud, but people just needed to actually see whats goin on inside their L03s instead of just listening to what other people are saying.

 

"but people just needed to actually see whats goin on inside their L03s instead of just listening to what other people are saying"

You called that one! I'd heard about the cast in swirl port thing but never really saw a picture of it. Geez it blocks off almost half the port. No wonder this thing has no top end (well the cam is to blame as well but even with a hot cam the heads would be a major limiting factor.. i mean just look at them!)

And yes I was referring to TPI heads as HO heads. I would just do the stuff without rebuilding the motor if it weren't for my mileage. And if these heads weren't the cost effective option they are, I'd probably leave to stock ones on as much as I'd hate to. Or just put off doing the rebuild even longer.

 

Maybe I can help you with some information about the potential of ported and polished stock heads.

My 305 L03 ‘H’ was tested on a rolling road (it was mounted in a Chevy truck) and it was then putting out some 220 hk on the rear wheels (I have no idea of how much that would be on the fly wheel?).

A TH 700-R4 was used with the following engine modifications:

Air cleaner: stock
TBI: stock
Fuel pressure regulator: adjustable
Ignition: stock
Intake manifold: stock
Heads: ported and polished stock
Cam: Comp Cams Xtreme Energy
Lifters: flat tappet
Rockers: stock
Pistons: stock
Exhaust manifold: aftermarket headers
Pulley: stock with A/C removed

PS. EGR removed and plugged, ECM mods unknown...

 

can you get rid of the swirl port hunk of iron on the lo3 heads?

can you make them work well? has that been answered?

 

No it hasn't been answered but I think that Dartbyu has them in his sig. Maybe he'll let us know how they did.

 

Aluminum L98 intake ports

 

Aluminum L98 exhaust ports...

 

Aluminum L98 combustion chambers...

 

those l98s look good. what do they run $$

 

I remember reading a guy's tech article about removing the swirl in the swirl port heads.
I don't think the article is on this site, but I hear about it here. You may want to do a search.
If I remember correctly, the guy basically just removed the bump, did a little other porting, polished the works, and said that he noticed a difference between the before and after. I don't remember any hard comparison facts like 1/4 times and MPH or RWH, but it worked for him.
I'll see if I can find the site again.

 

Well, I couldn't get www.sdpc2000.com to work right, so I can't give you an exact price.
They were around $700 stock. I paid ~$1000 for my ported set.

 

How do those L98s work on the 305? The valve centerline doesnt look very good so there might be some shrouding with the cylinder walls with those heads. The intake looks good but it still has those pushrod clearances that most heads have that really hamper the intake #'s. If you have ever seen the intake ports on the Vortecs, they benefit from an updated design that doesnt have the pushrod clearances. Have you ported the exhaust ports on your heads? From the factory the L98s have a poor line-of-sight. However they do have screw in studs which is always a bonus. I think that these heads would be a good idea if you bought them used for a decent price. If you're gonna go with some new heads and dont really have to worry about your EGR, go Vortec. That's just my opinion.

 

I got my L98 heads ported and polished from SDPC. They were a tad bit expensive, but they flow okay. They're good for >.500" lift right out of the box (bonus over Vortecs).

 

Yeah that's definitely a bonus over Vortec.

Theres something I wanted to mention here. I pulled the LG4 heads from a LG4 Camaro but when I look the casting # up they list as a Tuned Port 305 head. Very interesting since it's always been thought that the TPI heads were an H.O. head over the LG4.