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Hit it where you fit it
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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?
 

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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..
 

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afr

Better off buying them bare and building them with the parts you trust , jmo
 

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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!
 

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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.
 

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Bostick Racing Engines
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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.
 

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AFR is very flexible with what they will put in your heads if you get your dealer to call them and order them the way they want. Example: AFR can/will install springs like PAC and exhaust valves like Iconel if you want them to. They'll even hard anodize them for you, if you want.
 

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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.



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steelcomp was here
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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
 

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On my chevelle I bought a set of merlin complete heads new. It said the springs could handle a 700 lift cam and mine was only 640 so I thought I was fine. Nope, they broke and what really sucked was the fact they only had the stock type valve guide seals. I measured them and went down and bought a new set of springs- new problem dual springs with that cam pulled those stock type seal off the valve guide deal then starts the blue smoke out the exhaust..Then I had to pull the heads after I just finished the car! Moral of the story I even knew less that I know now and I would never do that again.... 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....
 

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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.



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Hit it where you fit it
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Discussion Starter #12
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

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.
 

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steelcomp was here
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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.
 

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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.
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.



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Hit it where you fit it
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Discussion Starter #15
The main reason I was thinking the 325's vs. 305's would be a larger engine in the works to replace the 468. I was going for the "one size fits all head" with a possible 540-555 in the future. Not the best plan but at least its a plan.:wink2:
 

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steelcomp was here
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The main reason I was thinking the 325's vs. 305's would be a larger engine in the works to replace the 468. I was going for the "one size fits all head" with a possible 540-555 in the future. Not the best plan but at least its a plan.:wink2:
That'll work! :)devil
 

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I will never install any out of he box head on anything without full dissembly and inspection/ and gauging. Seen too many heads come thru here wih parts that were not the ones as listed in the liturature, or not of the same specs. If a customer brings in his own new heads we completely dissemble them in front of him, so he sees what was in them. That prevents any "He said/She said" "These heads don't have the correct parts in them, you ripped me off". This is from many different head companies and retailers. Went thru that deal on dart heads a while ago for a customer, they pointed the finger squarely at the retailer. Retailer said they would re spring and retainer the heads if he would eat the shipping both ways! Wonder how many incorrect sets they sold to others. We installed Ferrea valves and comp parts, the customer will never order from that retailer again, and they are a biggie. Back to the question at hand: use Ferrea 6000 series intakes and Super Alloy exhausts for nitrous or blown deal to 15 lbs or so. Then Super Alloy for both above that. We have never had a failure wih their stuff. I won't go into it here, but we have a few sets of the heads in here with dropped valves "as factory provided for the ordered application". All 3 sets needed their chambers welded and new seats/guides. See old Hotboat magazine article: "Fubar or Fixable" as an example. Use a machine shop that you can trust, do what he says, and you have him as a "hero" or "zero". With most companies, the results will depend upon whom you talk to at the time of the order, and theres a lot of room for finger pointing. Do what makes you comfortable, but verify parts, clearances and cleanlieness. First. TIMINATOR
 
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