Yeah a locker is a definite plus. I had a one legger still on my truck after I did all my powertrain mods in late 2017. After the locker installation with a set of 3.90’s it was a whooole nuther world.
thanks to all. I just got my complete engine repaired. now pull hard. I have a t5 for later. The gear 3.3 I always repair my engine. But I always use stock parts, now I want more power and fun. but I don't know how to make a good combo.
This can be a broad subject but I'll start here. Are you merely wanting to have a little more fun or are you going for alot more power? Keep in mind that this stuff can be addicting. For instance.....once someone has modified their car somewhat and get a taste of what the power difference is....then more often than not a person "gets hooked" and then the REAL mods start happening. This stuff takes money though. I'm going to assume that the 3.3 means something in the neighborhood of 3.00 gears. The intake , carburetor, cam , heads and all those items will have peak power rpm range of their own so the puzzle is to match everything up to where all the rpm ranges work together. For instance, you don't want a cam with a power band of 2500-6500 and an intake manifold with a power band of say idle-5000 rpm. Serious mismatch there. Do some homework on engine recipies and parts that'll all match the desired power range. For playing around on the street and having a little fun then you can match most everything up between the idle/1500 rpm on up to say 5500 and still have some driveability if you don't get to radical with the cam profiles. ......meaning a little lope at idle is alright but a very rough idle doesn't work well with power brakes and things that require vacuum to operate. Rough & choppy idle cams sound cool and all but have trouble developing vacuum that's vital for power brake operation. Again this is all my experience talking but guidelines like these have always resulted in a good performing vehicle that's still fun to drive on the street. Just my two cents.
No problem with exhaust valve rotators? Add Trader Feedback The stock GT40 springs are too strong for a flat tappet cam. It will eat the cam and lifters after a while. You NEED to get springs that match that cam. So the springs that Match the cam are a option too
The Q&A on those springs say you can use them. I think the exhaust valve rotators must be re-used with that spring kit, as in the "notes" it says: Notes: designed to upgrade factory Ford 289-351W cast iron cylinder heads. Kit also includes valve spring shims. The exhaust valve rotators add weight to what your valve spring has to control, but since you are going flat tappet, you will have lighter lifters, and the exhaust valve rotators may not matter. When I assembled my gt40 heads, I used the alex parts kit for flat tappet cams because I had a flat tappet cam. Then I switched plans to a roller motor, and left those valve springs in. I think they were 130# closed. The stock gt40 springs are less than 100# closed according to my research. I have no problems with my valve train. I used gt40 heads with 175K miles on them, lapped the valves in after a little home bowl blending, installed with new stem seals. OK so far. I also had .040 milled off the bottom, so I had to shim my pedestals to get the correct valve adjustment. I should have had my intake milled a tiny bit, but I didnt. If it ever comes apart, I will get it milled.
I used a flat tappet cam with that spring kit on my F100 with a small summit K3600 cam, I wish I had gone bigger, but it is getting a turbo so I didn't bother. Alexparts is a great guy and I have used his stuff on a few things and he is very knowledgeable and helpful, wouldn't hesitate to use him. 110 LSA seems ok, it's a little tight, you might consider a 112, 212 duration is ok for a daily. I think the cam you chose is a a good choice for your goals. What compression ratio are you going to end up with?
I agree totally. 112 degrees LSA will make for a very noticeable idle and good power gain. Best of both worlds for optimum driveability on the streets.
These numbers will give you a wider power band which will work better with street friendly gear ratios. Keep in mind that if your heads, intake, and exhaust all get increased over stock sizes, better airflow fills the cylinder in less time, which translates to good cylinder fill with less duration. If you dont have headers, that increased exhaust duration will help....if you have headers it may not be needed. I was overthinking my cam choice big time. I even went to another forum and read 400+ replies by a guy named Buddy Rawls to try to understand cam dynamics better. I poured over countless cam specs, ran them through dynamic compression calculators, bought a degree wheel to measure cam lobes/lift, and read hours of stuff trying to understand and explore it all. So, what did I use? I ran low on funds, so I got a used 95 mustang GT roller cam. LSA 116, duration 211. Not optimum? maybe not, but the power band is everywhere and it is a fun car on the street.
I think one issue he is having is the fact that he is using a flat tappet cam, a roller would allow him to use some more aggressive ramps and still maintain a decent LSA. I would try the cheap roller lifters on Ebay or Amazon if it was my engine, but I am not eager suggesting somebody else do it. Also, you could get a used alphabet cam. Then you'd have something with a little more power and a little more driveability. P.S. if the video ever loaded then it is a 112 LSA cam at idle.
Everyone is right. I got the cheap Gt40 heads, the springs and the cam I need to buy. the headers and the intake will be for later. I will put them as soon as possible the heads and the cam.
The 289 and 302 like a tighter LSA, with no more than about 220 degrees of duration @050 (unless it's a race engine, different story) The XE256 does not idle rough. The stock cam in a '73 302 has a LSA of 108, but such a short duration that it idles smooth. The more modern roller 302s had more like 115 or 116 to work with fuel injection and a computer.
Comp cams says it's ok For a daily driver. Grind Number:XE262H Think the cam that gonna Buy it's this kit https://www.summitracing.com/parts/cca-cl31-218-2 High Energy™/Marine 218/218 Hydraulic Flat Cam for Ford 221-302. Good for daily driven performance vehicles. Mid-range power. Slightly lower gears. Mild rough idle. SKU
I don't recommend the HE268 at all. I had it in my 302. It was very sluggish even with 3.55 gear ratio, and after the engine warms up, it idles almost like a stock cam. I suggest the XE256, or if you have some lower gears and a looser torque converter, the XE262...
