Twisted wedge. What cam?

[Cobra4075]

Found a used set of twisted wedge heads for my 91. Whats the largest lift and duration I can use with stock bottom end? I have a custom grind laying around that I used with my 94 cobra which had afr's. The cam specs are .532/.536 with duration of 223/233. Will I be able to use this cam or is it too big for those heads? Thanks

 

[RARE NOTCH]

First off do they have the duel valve springs? second do you still have the stock pistons. if so then the cam is to big unless you change the pistons or have them fly cut for the valves. i just did those head on my notch with the stock short block
and used trickflow stage one cam. Hope this helps.

 

[88mouse]

The tfs 1 cam would be the best to use with them. I have a set that i just got back from the machine shop. If they are the street heat like i have. The only picked up 4 cfm after 500 lift. So going with a cam any bigger than that is just a waste.

 

[Grn92LX]

Most likely it'll clear easily. But you must measure if youre not sure.

 

[Grn92LX]

The tfs 1 cam would be the best to use with them. I have a set that i just got back from the machine shop. If they are the street heat like i have. The only picked up 4 cfm after 500 lift. So going with a cam any bigger than that is just a waste.

wrong

 

[88mouse]

wrong

Lets hear you side then.

I was there when they where flowed.

 

[white 89 GT]

The only picked up 4 cfm after 500 lift. So going with a cam any bigger than that is just a waste.

Someone must have screwed up your heads then, because that don`t hold true with mine.
When I changed from .520/ 224* to 550/232 i went from 12.08 to 11.68 and 2-3 mph.
And if thats only 4 cfm then
But I do have that set of heads for sale.

 

[88mouse]

The only thing i forgot to say was that mine are the first castings. Not the newer ones.

 

[white 89 GT]

I bought mine in like 1996
Mine are the among some of the early ones that had the bad valve guides, which is why last year I spent $650 to renew these heads after only 2k mi.

 

[5spd GT]

Peak lift only occurs for a tiny fraction in time. It is that period (dwell) just before and after the peak lift that is important in comparison to cylinder head flow. Therefore (for example), if a cylinder head has a good port shape and flow at .500", why not have a lobe profile x 1.60" that exceeds .500" lift so that the cylinder can take advantage of that .500" point.

Peak lift occurs at ONE point (ex. .500"), but .499" and below is hit twice. Does that make sense on why one may have higher lift than what a cylinder head can flow?

Duration is a sign of how spread the individual timing events are. Do not concentrate on a .050" duration number alone.

Peak lift has NOTHING to do with piston to valve clearance problems. It is the period of overlap.

 

[ls1beater4eva]

allso if you go to fox lakes website you can see that on a stock short block they are still running tfs heads with a tfs 2 cam and no problems what so ever.

 

[Modular2v]

Get an anderson cam! Im running one with my tw heads and it pulls like a freight train!