Thread:

AFR springs and hardware any good?

Originally Posted by Phat Bastard

Im looking to buy a set of AFR 325's BBC heads and was curious if they will work "out of the box" in a jet boat application. I plan to use a 270/280 @ .050" , .700" solid roller and spin to a 7500 rpm max. The have 250 seat and 650 open , .750" max lift springs installed.


Has anyone had any durabilty issues with thier factory hard ware?

Paging STEELCOMP, Paging Steelcomp..

What I was told was that AFR has the best parts out of all the head manurfactures! But, I still like to know what I have so I like to buy my own!

Been running AFR 335's on my 565 BBC for 4 years. 765 lift Straub cam turning 7400 with no issues at all. I change springs after every season though.

Originally Posted by Phat Bastard

Im looking to buy a set of AFR 325's BBC heads and was curious if they will work "out of the box" in a jet boat application. I plan to use a 270/280 @ .050" , .700" solid roller and spin to a 7500 rpm max. The have 250 seat and 650 open , .750" max lift springs installed.


Has anyone had any durabilty issues with thier factory hard ware?

Valves are made in India. I prefer Ferrea... even though they are forged in Argentinia... still a damn good part. May want to consider an iconel exhaust while your at it.

I'd be more concerned about how much boost you plan on running and going with a bit more spring pressure on the seat. But that's just me.

there is something wrong with the AFR catalog. It shows spring Package #8031 PAC 1.625 PAC #1224 spring with 275 on the seat @ 2.00 and 810 open with .850 max lift. and Ti retainers. NO WAY that spring is the standard spring!!!!

Its more like Spring Package #8003 with a 1.560 chrome silicon spring, electro plated, 250 seat and 610 open with .750 max lift and a steel retainer. I believe its an Associated Spring and it works OK. Maybe a little light for the RPM you're looking to spin, specially with a steel retainer. This is more like the spring the OP discribed.


The only set of heads I ever bought assembled were AFRs. Still tore them down and checked them outI ordered them with Victory 1 valves which are severe intakes and super alloy exhaust. They are holding up fine. They didn't offer Ferrea valves at the time, which they do now. But I have zero complaints with the victory valves.
I also ordered them with Manley Nexteks. They didn't offer PACs then, but do now. They Nexteks were done within a year. I can't slam the springs because they really are a drag race spring and in that application they may have gone 3-4 seasons.


If the heads don't come with the CNC'd chamber standard yet(they should!!!!!) them you either need to get that option, or have somebody clean up the chamber. There is suppose to be some flow gain with the tuliped exhaust valve as well. It not cheap, but its a good valve.

I'd think I would just call Steelcomp and have him set them up. REV intake valve, AFR tuplip exhaust, PAC springs, and set up ready to bolt on.

Are you running boost or power adder?
Main thing about AFR is their guide clearances. Way too tight (imo) for marine use, espcecially boosted. They even say so in their literature. You will need to have them honed accordingly.
They can always use a 'touch up" on the valve job. Concentricity issues.
If you're buying as-cast heads and you're using advertized flow numbers for your cam selection, verify the flow numbers! This is the case with ANY as cast head and nothing against AFR.
As far as component quality, there's nothing at all wrong with AFR's valves and springs, but like everything...there's always room to improve.
My recommendation for any assembled production-line head is disassembly, inspection, thorough cleaning, and reassembly. I don't think I've yet seen an assembled head I personally would put on an engine and run, unless it came form someone like Alan Johnson.
JMO

Originally Posted by tkriley13

Last part I`ve always wondered is that when the springs broke could that possibly dropped a valve? seems like I was really lucky since the spring pressure was loose....

You were extremely lucky! Yes, you can drop a valve from a broken spring. More importantly, when a spring goes into coil bind, it ususally results is a trashed camshaft and/or broken lifters as well.

Originally Posted by Phat Bastard

No boost but I do plan on a 200-300 nitrous set up. I have an 11:1 468 and feel the AFR's are the best bang for the buck in the $2200 range. From what Ive read they seem to be the best flowing head in the size range Im looking for (325 runner) , non CNC of course.

Ive had good luck with Isky Gold stripes (PSI brand) in the past and I have a set of 9995's (250/675) already so a bare set of heads may be the way to go. I was able to get 2 seasons out of a set that I drove the snot out of. Never broke one, they were just about 10-20lbs under when checked.

YUou'll be way ahead of the game if you go with a set of 305's on your 468. No reason what so ever to run a 325cc runner, no matter how much NOS you're running.
The Iskys are one of my first choices along with Pac. Just about every spring made will lose about 2-5% pressure almost immediately.
You might consider an inconel ex valve as well.

Originally Posted by Phat Bastard

Ive had good luck with Isky Gold stripes (PSI brand) in the past and I have a set of 9995's (250/675) already so a bare set of heads may be the way to go. I was able to get 2 seasons out of a set that I drove the snot out of. Never broke one, they were just about 10-20lbs under when checked.

Originally Posted by steelcomp

The Iskys are one of my first choices along with Pac. Just about every spring made will lose about 2-5% pressure almost immediately.

I agree. Your gold strips lost the much right away. The 99XX Iskys are almost impossible to break. They will lose pressure, and eventually get to a point they need to be replaced long before they break. The inners will break, and I replace them after a couple of seasons. We have yet to kill a gold strip but we are working on it.