ScottyRS

iTrader: (2)

I heard a rumor that Air Flow Research used to produce aluminum heads specifically for 305 engines. Is it true? And where can I get some?

ThirdGenFire

Dude no kidding. Whats the word on that. I want to know if there are other choices besides World Products and getting 350 heads to work.
Anyone know???

25THRSS

they don't make them anymore. If you really want them the only way is to buy a pair used, but good luck on that.

ThirdGenFire

Bummer. Wonder who else makes 305 heads besides World.

Willie

iTrader: (1)

I bought probably the last set of AFR 190s for a 305 in December, 2001. One month later, I contacted AFR and was told they no longer make them.

ScottyRS

iTrader: (2)

Do you know the part number for those?

David @ Thunder

I don't remember AFR having a specific head for the 305, but the new version of the 190 is currently a 180cc. It's the same head with a smaller port. Basically it goes 180, 195, 210, etc. IMO, a set of 180's with 1.94/1.5x valve, Comp 212/218 Extreme Cam, fully ported TPI, headman 1-5/8" long tubes, Vigilante(if auto), etc. would make a very stout 305. Pricing for the 180's start at $1299.

Chris89GTA

iTrader: (2)

The 180 AFR head would work well w/ the cam that Dave listed, and maybe a slightly bigger one if any one got frisky enough to run a Hotcam in a 305... If i had stuck w/ the 305 longer I was gonna try that...

Jstcrzyengh

iTrader: (2)

The 305 head was a 180. I believe the valves were smaller than 1.9/1.5 because of the worry's of clearance with the 305 as well all know sucks. With a hotcam that setup would be REALLY lumpy and the 1 5/8ths would restrict the air that the cam would be pulling through those heads. Heck the hotcam in a stock 350 is a lumpy cam. It even has noticeable idle in most 383's. You would keep more bottom end torque though.

Mark 89Formula

AFR didn't make a 305 specific head like David mentioned. Turns out that the AFR 190s with 1.94 intake valves has enough bore clearance on a 305 so that's what AFR sold you if you wanted a set of heads for a 305. Willie bought one of the last pair of 190s they made with the 1.94 intake.

Jstcrzyengh

iTrader: (2)

Hate to correct you, but they were expressly marketed for the 305. It wasn't something that just happened to fit. Now did they work on a 350 as well? Of course it's an SBC, did people by them for the 350 as well? sure, but they were known and made as a 305.

Well, doing a little research doesnt yield a lot since they havent made them in so long

http://www.flatlanderracing.com/afr180cc.html

But that gives you a little bit where the mention the 180 305 heads.

Willie

iTrader: (1)

I cannot locate any of my original paperwork I received with the heads, but I do know the following specs:

AFR 190 with
1.94" intake valves,
1.55" exhaust valves, &
57cc combustion chamber volume.

Does this make my heads 305 specific? I think it does, doesn't it?

Willie

Mark 89Formula

I'm not feeling too corrected. AFR never marketed a "305" head like World Products with their S/R 305 Torquers. You won't a find a 305 head in the AFR catalog. The valve size is just an option you could select when ordering a set of heads, not a unique part number. The valves weren't smaller than 1.9/1.5 as you guessed in you first note; they were 1.94/1.55 per you own link (which is just a page from the same AFR catalog I have). You most assuredly could get the small valves in the 190 head long before the 180 existed. It makes sense they would push people towards the 180 once they brought the smaller head to market around 2000. There, that horse is thoroughly beaten.

Mark 89Formula

No, that makes it an AFR 190 with the valve diameters and combustion chamber volume of your choice. Does workly nicely with a 305 though, doesn't it.

Willie

iTrader: (1)

Yes Mark, they work rather well.

56cc, not 57cc.... geez....

and here's proof:

Jstcrzyengh

iTrader: (2)

Willie you always come through. I knew I wasn't crazy. Well, Just crazy enough

But I remember speaking with AFR way back when about their 305 heads. I knew they had the smaller CC and valves

To Mark:
If they weren't for the 305 specifically (which has 58CC heads) can you imagine the CR ratio with those heads compared to the 68CC/74CC that they sell their 350 heads at.

Mark 89Formula

You're absolutely right. But keep in mind that the L98 AL heads on the Vettes and ZZ engines also came with 58 cc chambers so plenty of guys with the larger bore SBs get the chambers milled too.

We're pretty much in violent agreement. A set of AFRs with 1.94/1.55 valves and a small chamber is for all intents a 305 specific head. What I'm trying to say to those who are looking for a set for their car is that you won't find "305" stamped on the head or cross referenced against an AFR part number. So if you come across a set that are purported to be for a 305, get out your calipers and burette. That's the only way you'll know for sure. Peace.

BTW, Willie, did those AFRs make your car any faster?

Jstcrzyengh

iTrader: (2)

Somehow I knew you were going ot mention the vette heads

You do realize though that the vettes uses different pistons to give a different CR, as well they are aluminum heads and higher CR ratio is needed.

Willie

iTrader: (1)

BTW, Willie, did those AFRs make your car any faster?

I do not have any empirical data to say either way. That was almost three years ago and at the time I installed them, I made other changes too. The primary reason why I switched from Corvette aluminum to the AFR's was the substantially thicker deck height.

Willie

ThirdGenFire

Sounds mighty interesting. I think I might need to try out these 180 heads of AFR. Maybe when the bills let up I can buy them.

wesilva

iTrader: (35)

I was lucky enough to find a set of the "305" AFR's on eBay several months ago. Those interested in them should search there. I see them from time to time. They are cast "190SHST" so they are easy to identify. They came standard with 1.990 intakes and 1.550 exhausts. As with most AFR's you could get them with the CNC porting for an additional cost. Larger valves could be fitted as well for those looking for a small chamber and not necessarily for a small bore application. That would be me. Mine are fitted with 2.05 intakes and 1.60 exhausts. I wish I could tell you how they work but the motor they are on is not running as of yet. My only disappointment so far is the fact that I removed my rocker stud and the darn helicoil came with it. Had to round up the necessary tools and a new helicoil. Pain!

wesilva

iTrader: (35)

Chamber and valves. I almost felt guilty about the $685 I paid for these. I was sure they were going to need extensive work but....they were CNC ported by AFR and fitted with the larger valves. They saw very little use and all I had to replace was one guide. Stuff like that never happens to me. I'm the guy that pays too much for stuff....thinking I got a deal.

Trevor86TA

Lots of guys build motors with big compression ratios. Some think its adventageous to use smaller chambers and flat tops rather than larger chambers with domed pistons. 58cc heads on a 64cc equiped L98 would still give a completely streetable compression ratio.

92GTA

iTrader: (11)

I'd KILL for the AFR 190 305 heads right now!!!

As per AFR, I'm having to buy their bare casting heads and have my local machine shop port/polish and install my valvetrain of choice, 1.940/1.550 valves size and all. I'm paying $764 just for the heads from AFR

Anyone want to sell me a set of these AFR 190 30 heads? :hail:

JPrevost

Oh darn , no 305 AFR heads
Looks like you have one more reason to put in a 350 .











..... j/k , good info, I never knew they even had a 305 head. I'd go with a thin gasket and vette L98 heads ported and resurfaced.

ScottyRS

iTrader: (2)

That'll work just fine.