305 High output Heads ?

[bigblock79]

305 High output Heads are they worth any thing. a buddy of my got a 305 ho out of a camaro. says the heads is high dollor what do ya thank.

[streetstar]

Originally Posted by bigblock79

305 High output Heads are they worth any thing. a buddy of my got a 305 ho out of a camaro. says the heads is high dollor what do ya thank.

They are worth it if you are putting them on another 305, but they have small valves for anything bigger and the combustion chamber volume is small as well, so you really have to watch your piston selection

The complete motor would be worth it if it was cheap, but the heads alone are useless for most people with bigger short blocks

[gchemist]

Unless: http://www.goingfaster.com/spo/modthel03.html

[MylilBowTie]

That is one of the most misleading websites. There is tons of misinformation on that. Thirdgen.org would be a place to look up better info about the heads. There are only a few years for the "H. O." and some are called that even tho there not.

[streetstar]

Gchemist, i can't tell if the BS flag is about using 305 HO heads period, or whether it is referring to my opinion that the 305 heads are worthless unless used on another 305.

The web link you posted seems to support what i said - that motor was designed as a system that can be improved upon because the parts are all balanced in unison (what we should be doing with any engine) --- but the individual heads would not be as effective as say - an off the shelf SR Torquer head for a more typical 350.

I think they would work fine on a 305, but only if the engine builder retained the roller cam setup that was used a lot on the F bodies of that generation --- pair it with a regular cam and they will not live up to their meager potential.

Vortec heads are 280$ apiece completely built and ready to rock , so there is little reason to mess with most old heads (unless they are cheap and budget is a serious issue for the build)

[Pyrotechnic]

I don't understand that website's reasoning behind building a 335 instead of a 383. When good 350 blocks can be had all day long for cheap, why spend the money to clearance a 305 block for a stroker crank ? All you're doing is cutting down cubic inches and shrouding your valves.

Now if you have a good running 305 or one that is a good candidate for a rebuild, I see nothing wrong with swapping out cam and heads and making it efficient.You would probably end up with a 300+ HP motor that got great mileage too, but a 305 stroker ? Still don't see the reasoning.

I would go with Vortec heads if I was on a budget.

[RatPoweredTruck]

Originally Posted by bigblock79

305 High output Heads are they worth any thing. a buddy of my got a 305 ho out of a camaro. says the heads is high dollor what do ya thank.

Think about it. 305 heads were designed for 305 and smaller...if you want real gains out of your engine, whatever it may be, you have to keep focused on the basic stuff. Basically, more air/fuel "pumped" efficiently through your engine equals more power.

[OJ1988]

305 heads are a waste of time, and money.

Great anchors for a jon boat though!

[OJ1988]

What a funny site,


"Face it, the only real difference between a LG4 powered F-body and the L03 powered F-body lies in what is sitting on top of the motor, the only real difference is the type of induction system. Other than the form of induction, that being either carb or TBI, they are both 305s, in F-bodies, and respond to the same basic mods to go faster. Once you realize that the ONLY difference between a 305 LG4 powered '87 Formula and a 305 L03 powered '88 Formula is the highly restrictive intake manifold and the Rochester Model 220 TBI unit, you are fast on a road to realizing that most of the hoopla behind TBI being 'bad' is just total nonsense"


The only bad thing about the TBI engine is the TBI! Duh! I think he just lost the augument to himself!

[SSC's76]

LG4's and L69's came with the same heads 1st gen TPI setups had 416's on them as well for a short peroid of 5 months before they switched to the centerbolt style heads with the swirl port POS heads.

A set of 416 or 601 heads can flow plenty for a mild SB and increase the compression ratio by a full point. If you have a budget build going with stock pistons and a mild cam the smaller 1.88 valves will not limit you power wise below 5K. Usually 4500-5K is where most street setups stop making useable power anyway.

Now you need to take into consideration that the increase in compression requires higher octaine fuel or reduced timing to avoid detonation. Right there we have a problem most people will run the premium gas for only so long and then go back to running the cheaper gas and reduced timing to stop preignition. That 20 hp you gained by bumping the compression up is lost.

[SSC's76]

Originally Posted by OJ1988

What a funny site,


"Face it, the only real difference between a LG4 powered F-body and the L03 powered F-body lies in what is sitting on top of the motor, the only real difference is the type of induction system. Other than the form of induction, that being either carb or TBI, they are both 305s, in F-bodies, and respond to the same basic mods to go faster. Once you realize that the ONLY difference between a 305 LG4 powered '87 Formula and a 305 L03 powered '88 Formula is the highly restrictive intake manifold and the Rochester Model 220 TBI unit, you are fast on a road to realizing that most of the hoopla behind TBI being 'bad' is just total nonsense"


The only bad thing about the TBI engine is the TBI! Duh! I think he just lost the augument to himself!

Actually your wrong. There were different cam grinds in pre roller f-bodys depending on designation. Different exh manifolds and pipe diameter too but thats external. TGO like metioned above is a good source for this information just take a look at the FAQ section on the main site.

[OJ1988]

I was just quoting what the guy said on that site.

I was just stating that he says the TBI are great, yet on the site he says the TBI is the limit.


I am very familier with the 3rd gen, have an 88 IROC and the 350 rollor motor out of it is in my truck now.