Fox Trick Flow 170’s on a 331 Stroker

I am trying to clean up my motor. I have a set of Trick Flow 170’s. Question is will going to a 331 stroker be worth it? Or should I just clean up what I have and go with a 306?
I have a trick Flow track heat upper and lower to go along with the build.
 
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While they are maybe not the most optimum head for a stroker, they will work just fine. I have them on my 347 (bought it built already), and it runs well. Made 330hp and 350tq at the wheels with a tubular GT40 intake and unfinished tune. If the stroker kit is in the budget, I would do it for sure.

Also, being you bought the track heat upper, it will benefit from more cubes. On a 306, your torque will suffer from it. Easy enough to swap it for a street heat though.
 
I know some guys who have been real fast with them . I ran 10.80s with mine on my 347 and went mph for low low 10s . Is it ideal ? No I upgraded to a 20511r . It will work esp if you aren’t looking for every last hp out of it .
For comparison I made 620 in one pull with the 205 11r at 12 psi at 6000 with a built Aod

where as with the 170s I made 640 at17.5 around 6200 with a Tko 600

You can say the engine benefited big time from the air flow .
 
If I am reading the question right, you are asking about upgrading the short block, not the heads. I would say no. Those are great heads, but they won't flow enough to make it worth it to increase the displacement. You're only going to move peak power from about 5500rpms to about 5200rpms.

Kurt
 
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It's a lot more money for very little gain. Well basically no gain as far as I can tell. Now if this were a power adder combo, where you would be buying a forged crank, better rods, and pistons anyway, that would be different, because the prices would be about the same between a 306 and a 347. If it's just going to be NA, get a parts store shortblock 306, and throw the heads on it.

Kurt
 
Unless you also boost it :nice: but... building a stroker [for] a set of 170s would not be my first pick either. If the plan is to eventually upgrade the heads as time and money permit: Press on with pride.
That’s why I gave that example .
 
I currently have the TW 170's on my 347 and am looking to upgrade to bigger heads and cam. It runs good but if you're looking to go stroker it's obvious that you're looking for more than what the 170's can provide. Those are super heads for a 306.
For what it's worth, my 347 with the 170's puts out 360/395 to the wheels.
 
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Years ago I had TW 170's on my 347. Made 371hp @ 6200 rpm on a mustang dyno. Go with the stroker short block. Don't waste your time with a 306, do the stroker (go 347). That'll be your foundation you can always improve down the road.
 
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If you boost it, you'll get to max stock block limits without a problem with the stock 302 rotating assembly. So, if boost or spray is in your future, then just leave the displacement alone.

If you will stick with n/a, then stroking makes sense, but as Mike stated the 347 makes a lot more sense than the 331. Same price, same reliability, more power.

TFS 170s are good heads, and though they will not be optimum for increased displacement, you will see more power with them on a stroker than on a 306, assuming cam & intake support it.
 
Hey man,
I'd say go for it! Those heads are plenty enough to make a 331 rock n roll, and in countless chassis dyno runs I have seen VERY LITTLE difference in similiarly built 347s vs 331s. Are those heads the highest flowing model on earth?...of course not. However, they DO flow enough to support over 500hp, which in reality is probably more stress than you want on a factory block anyway; unless I miss my guess. And with that good intake you've already got, a well spec'd 331 with the right amount of static comp. to support whatever cam timing your wants and needs dictate, can and will make enough power to actually hurt itself...which should be considered "plenty" in any case, no? DSS makes a really nice, lightweight 3cc flat top for the TFS heads that hangs on a 5.315" rod, which will put you really close to 10.5:1, assuming a .030 overbore and just a clean-up cut on those heads, with a 0 deck. I'd say close your intake around 64-66 degrees ABDC, and stick with a 112 lobe sep, putting you in the 272-276 advertised duration range, with lift around .550 on both sides (provided the heads are sprung right), and maybe something like a 6-8 degree split. It'd be easy to tune, SHOULD get you in the 425-450hp range with gobs of torque, all before 6000rpm, which means it should outlive us all with proper maintenance, and it would run on 87 octane dog water as long as you don't get it hot. Trick Flow made 350hp and 370ft/lbs with those heads and a li'l baby cam with substantially less lift than the heads will support, on a 9.5:1 306, right?....well, if anyone disagrees that another point of compression, a little more cam, and 30 more cubes through a quarter inch more stroke should easily net a guy another 75+ ponies and the torque to go with it, I'm all ears. Either way, I look forward to updates on your build, and hope it all goes smooth and you have a ball doin' it, bud!
 
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There is this option for the TW heads as well, several stages available. Depending on what you could sell your TW heads for and if you have good hardware on them already, you may be better off going this option if looking for better heads.
 
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Take the extra displacement. It comes at no cost. There are reasons to build a 331 over a 347, but that's only relevant to high-boost applications and/or parts you already have. -Chris
 
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Good post, Ive got my block at the machine shop now and deciding on what 331 or 347 kit to go with. And a fresh set of Trick Flow Twisted Wedge 170s to go on. Should work fine for my street car. Looking for an easy 350/350, should suffice.

Standby. This post changes everything. If you are going to buy new heads anyway...GO BIGGER!! I'd rather have TF 185cc heads on an O'Reilly $1200 302 short block than TF 170cc heads on a $6000 CHP 347 short block. I can tell you which engine will deliver more smiles guaranteed.

Kurt
 
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Standby. This post changes everything. If you are going to buy new heads anyway...GO BIGGER!! I'd rather have TF 185cc heads on an O'Reilly $1200 302 short block than TF 170cc heads on a $6000 CHP 347 short block. I can tell you which engine will deliver more smiles guaranteed.

Kurt
I already have the heads. Lol
Block is at the machine shop.
Havent bought any rotating assembly yet.
 
Disagree. Buy some $200 SpeedPro pistons with good valve relief on ebay, machine the rest, and throw it back together. A 347 rotating assembly is $1800 down the drain. You get nothing for that money. You get 20hp from a $400 custom ground cam, you get 2hp from a stroker assembly with those heads. There are better places to spend you money.

Kurt
 
Not saying your wrong but... cid will at the very least add useable torque, I am attaching a link to an article done where they used a 393w and ran a set of e7 heads on it they flow miserably low numbers as we all know. The 302 only made 210hp in this trim but a 393w made 387hp and 461tq with the same heads. Albeit a much larger cam.

 
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I'm ambivalent. I could make an argument in either direction. I know a forum member whose car I absolutely love that put a Cobra intake on his 333 stroker. Not everything has to be optimal, and it's hard to beat TFS 170s on a budget. But, yeah... you could definitely do better. At the same time, I'll bet a stroker does pick up some decent power on those heads going from a 302 to a 347, as long as the rest of the hardware supports. They aren't GT40 heads, and most 302s aren't making what Mike's car (Grn92LX) did with them on his 347.