I was wondering if anyone knows if I would be able to run afr 165 with the flat top pistons that I am currently running?
Can I Use Afr 165's With Flat Top Pistons
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Probably not but you won't know for sure until you clay it up. The TFS heads fit (usually) but there are still some cam limitations.
Soo, best bet and I suppose only option would be to take the car into the speed shop have em tear the top end down and see what heads I can run? The cam is not stock either by the way.
No... running a stock cam with a set of TFS heads will likely not give you any problems at all. The trouble is that a stock cam will also not give you everything those heads are capable of.
Give Trick Flow a call when you're near ordering. Ask them about the cam that you need for flat top pistons. They'll lay out the max duration and lift for using their TFS 170's over the top of those pistons.
Make SURE you know what block and pistons you have... For example: Stock pistons for a 90 are different than the stock pistons for an 86. It does make a difference.
I just realized that I didn't even ask you what pistons you're running. LOL
In a 90 for instance, the stock pistons are fly-cut. You can run heads that you wouldn't be able to run over the top of 86 flat-tops.
Where did your flat top pistons come from?
In a 90 for instance, the stock pistons are fly-cut. You can run heads that you wouldn't be able to run over the top of 86 flat-tops.
Where did your flat top pistons come from?
Well the car I'm working on was my dads and it's a 95 gt. I need to and don't know why I haven't pull out the build sheet and take a look but I know that it has flat tops of some sort and a comp cam that is fairly mild but Im not sure the duration off hand. I was just kind of dreamin' up a parts list. When he had it rebuilt a couple years a go the builder was old and did old school methods I believe. He just did a 3 angle valve job on stock heads and the cam that he put in wasn't copoperating with the computer so he had to have a dyno run and put an sct chip in. The flat tops were put in during the build as well. It's not making the horsepower numbers that one would hope for after the $ spent so I was thinking that heads would be the thing to do. So all that long rambing being said, if it indeed has flat-tops in does anyone make a set of heads that I would be able to run? I'd like a good steetable head that doesn't require 7k rpm to start making power.
The TFS heads are still going to be your best best unless you change or fly-cut the pistons. No matter WHAT head you decide on though, piston to valve clearance is going to need to be measured.
There are some assumptions that can be made if you're running an OEM bottom end but if those parts have been swapped then there's no telling.
There are some assumptions that can be made if you're running an OEM bottom end but if those parts have been swapped then there's no telling.
one more thing and I'll let ya go:
Yeah don't really want to mess with the pistons mainly due to money of course but as they are now the motor is running 10:1 compression. I know everyone says ported e7's are not worth the money but I found a guy on the net "Thumper of Orange Park" that sells ported e7's for $695 and the flow numbers look to be ok. I know it's not going to make 350 horses to the wheels with em but for the money might be ok and if I'm assuming correct since they are e7's they ought to bolt right up correct? http://www.hunterstyle.com/thumper/
Yeah don't really want to mess with the pistons mainly due to money of course but as they are now the motor is running 10:1 compression. I know everyone says ported e7's are not worth the money but I found a guy on the net "Thumper of Orange Park" that sells ported e7's for $695 and the flow numbers look to be ok. I know it's not going to make 350 horses to the wheels with em but for the money might be ok and if I'm assuming correct since they are e7's they ought to bolt right up correct? http://www.hunterstyle.com/thumper/
I wouldn't spend $700 bucks on iron heads, probably not even ported GT40's. You can probably find a used set of TFS for $700. I would definetely find out what kind of pistons you are running. A flat top piston can have valve reliefs and still be considered flat tops. If you have valve reliefs, the AFR's would probably work out for you; although, you should always check your PTV clearance. The TFS heads are a good choice as well.
Joe
Joe
I was unaware that the pistons could still have valve reliefs, thanks. $700 is a bit much I suppose for a set of iorn heads that have been ported, but buying a used set of aluminum's isn't that good of a deal either. Let's say you bought a used set of trickflow's for $700, are you really gonna put them on your car without a trip to the machine shop? I mean you don't really know what you have when you're buying of the net, and by the time they've been planed, and new springs, ect put on you savings are out the window. So when it comes time to buy heads what do you do, take care to shop have them tear the top end off and see what type of aftermarket head will fit and then throw it back together, get on latemodelrestore.com order the heads and then take it back to shop and have them installed? What a headache, pun intended. Should've gotten a topend kit from the get go I suppose. As of now I have rebuilt stock heads, stock valve size w/ 3 angle valve job. Cam specs are 281 281 220 220 .512 .512 110° Those damn flat top pistons I swear...
in short it depends on the valve events (peak lift means jack 
) and how much free drop you have. so you have to degree and clay it to know. can an aftermarket cam clear flattops? hell yes it can and not just with a twisted wedge. but there is only one way to know yours will.
if you have an HR cam that has a .050 lift intake open event after TDC it will clear, if the exhaust .050 close event is before TDC itll clear. but to know the cam is right takes a degree wheel and at that point you might as well check PTV clearance.
fwiw i have never seen an AFM N41 not clear, IO is 1* BTDC and the EC is 5* BTDC
) and how much free drop you have. so you have to degree and clay it to know. can an aftermarket cam clear flattops? hell yes it can and not just with a twisted wedge. but there is only one way to know yours will.if you have an HR cam that has a .050 lift intake open event after TDC it will clear, if the exhaust .050 close event is before TDC itll clear. but to know the cam is right takes a degree wheel and at that point you might as well check PTV clearance.
fwiw i have never seen an AFM N41 not clear, IO is 1* BTDC and the EC is 5* BTDC
