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Discussion Starter #1 (Edited)
Right now I have a fully forged 383 compression is 9.5 to 1 with moderately ported older sportsman IIs 200cc runners, 65cc chambers, 2.05/1.6 valves, comp cams XE 294 hydraulic, weiand 142 blower, stahle performance 850 blower carb, 3200 stall, 9" w/3.50 gears.

One of my buddies is upgrading to a set of monster Pro 1s and will sell me his 2yr old AFR 210s 76 cc chambers, competition ported heads. They have roughly 30 1/4 mile passes and 15 1/8mile passes for 925 bucks. Is it worth the moolah to pick these heads up for the amout of power I could potentially gain from them...main reason Im interested is newer technology, weight, looks, and help on compression ratio in regards to the lil blower...mainly a street motor with a couple week ends a year at the track....Advice, rants, attaboys, youre a fool, and all udder comments appreciated...I dont know much about the AFRs aside from the bit of reading Ive been doing the last couple days on the net....only real drawback I can think of is my heads (sporty IIs) are straight plug, and his AFRs are angled
 

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jammn73

those afrs will totally wake up your combo and for $925 what a deal id get them checked out though just to be on the safe side
 

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jammn73

i just noticed that the afr 210 ur talkin about are 76cc so that will knock your compression down to about 8-1 something to think about
 

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Definitely better heads!!!:yes:

Just watch your headers and spark plugs!!! You're likely to run into needing different headers as well.:rolleyes:

I'm not sure (with that little blower) that you're making enough boost to really benefit from dropping the compression that much. That would put you into 6-71 territory.:devil: Time for a blower upgrade?:D

Simple answer.......for a few hundred $$ more, you can get a great set of NEW heads that will go right in place of what you have without all of the potential headaches and added expenses.:yes:
 

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$925.00 is a great deal for those heads. However, you're going to lose around one full point of static compression ratio with the head swap. This loss of compression is immediately going to offset any HP gain provided by the larger runners and improved air flow. You're going to be disappointed with the results.

On the plus side those AFR heads give you a lot more room to grow into for the future, and you could easily sell your Sporstman II's to recoup half or more of your investment in the AFR heads. If the budget allows I would pick up the AFR's and save them for another build or to swap onto your existing engine if you decide to increase the size of the supercharger and boost level.

If you have fenderwell headers then the angle plugs are no big deal. If you have chassis headers for a stock clip then you may run into problems.
 

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Discussion Starter #8 (Edited)
I was worried/told that my compression was waaay to high for that little blower at 9.5 to run anything but race gas ALL the time...I only have about 50-100 miles with it on there as it got cold quick in the mid-west and i put it away for the year so nothing is really dialed in aside from the old (ear/seat time tune) I havnt even wired in my boost retard box yet...the little I did drive it I ran a mix of 91 and 110 race gas in fear of detonation...LOVE the torque it added down low tho.

I have some junk small tube hedmans on there right now so if I had to dent a tube or two it wouldnt break my heart.

that set up minus the blower/blower carb with the old vic jr and an older 830 Dper ran [email protected] 110 crapola 1.79 60ft....I was hoping those heads coupled with that little blower were the last pieces of the puzzle to push it into the mid 11s or better....sure Id love 10s but im not gonna put a cage in the car...I mainly take it to car shows/cruises and a couple week ends a year at Rock falls/Earlville for bragging rights with the buds.

Yes I understand thats a heck of a price...but its also a buddy price...I prolly have as much wrench time on his car as mine...lol...but damn near a grand goes a long way to getting me closer to my aftermarket front clip...thats why Im wondering if those heads would be the way to go heard some good things about those AFRs especially vs my home ported sporty IIs.

Id love a 671/871 but I like my warm bed even more and my *** would be sleeping out in the garage if I did ALL the things i want to do to my little duece...thanks for all your responses folks
 

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Ya, 9.5 is a bunch for a super/turbo charged engine. if you're able to up your boost then a lower compression engine is better and easier to tune since the added psi is exponential. there's a reason why engine builders keep it low.

if you let go of the your sportsman 2's let me know.
 

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The alluminuim heads will help with detonation if you have any, and its probally a solid 60-80 hp increase, its a no brainer, good luck:yes:
 
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