351w Upgrade Ideas- Dyno Sheet Included

[Stang_1973]

Ok let me start off by saying my car is a 1973 coupe but all its "guts" are based off a foxbody. It has a 351w EFI, 60mmTB, lighting GT40 tubular intake, perfromer rpm heads, X303 roller cam, full length headers, dual 2.5" exhaust. I posted this thread in classic but havent had any responses.

I also did an AOD swap with a 2500k stall, i believe. the original AOD i used, even though was rebuilt before installing, broke about 3 months after getting installed. bent the input shaft on a downshift.....
This lockup(stock) AOD setup put down 305HP to the wheels and 360lbs o TQ. Red lines in the graph.

After the it broke down, i was convinced to go non-lockup and procured a used edge racing converter, lentech valvebody, and all the other nonlockup goodies. according to my Mechanic this AOD should hold up to 600hp, buuuut as the graph shows i suffered in power to the wheels. I sent the converter to edge racing who retooled it to 3500 stall speed, per my mechanic. This setup made 290/355 and the power band look way different than the lock up AOD.

Now im not sure what direction to go becuase i know there is more potential to get power to the wheels.

Id like to go back to lockup since according to my graphs i had a longer powerband and obviously put more power to the wheels. but how can i make sure i dont break my tranny again?

Next i know the GT40 tubular is limiting power, but nor sure what intake to go with. ive considered, TFS, and Eddie Victor...

Also i know the Xcam is old tech, if i can get the right setup i think id spring for a custom cam.


other info- car has power brakes and a/c, is used as a weekend driver, and every now and then as a daily in nice weather.


point me in the right direction!!!

 

[FoxMustangLvr]

I honestly don't know what your typical non-stroked HCI 351w is good for (maybe 350rwhp with good heads) in the HP/TQ department but you always have to look at the heads first and go from there. Those Eddy RPM's would barely be ok for a 302cid engine but really some better heads are in order IMO for your engine. Maybe some AFR 185's or Trick Flow 11r's but that's a big investment. I know it's easy to recommend thousands in parts but in the end that's what it really takes. If you want to keep the current heads then I'd recommend adding boost and changing the cam. I don't think your AOD is limiting your HP, your heads and cam are.

 

[broncojunkie]

Your 60mm throttle body is a choking point too, I believe. It's ok for a 225hp stock fox body, but it's not helping a 351 breath any better. The tubular intake is nice looking but most of the aftermarket intakes will outflow it. And yes, you would also benefit from some better-flowing heads. I would throw and bigger tb on it and see if you can feel the increase in power. Then go from there, depending on how much you're willing to fork out and how much you want to get out of it.

 

[CarMichael Angelo]

I'd also imagine that a 351 w/ a stock D9AE head would probably be good for about 250WHP, and that with a cam, intake, and headers would be good for maybe 300 whp. That said, I'm saying The current heads are why you see good torque, but lousy HP.

As stated, The bigger Windsor is gonna need at least a 185cc head to adequately feed the larger demand for air.
The fact that both transmissions corroborated the HP numbers w/i 10HP is a tell tale. Gotta get more air into the engine.

As for you breaking your input shaft,...An AOD input shaft is a potential weak link. They make upgraded two piece units if I'm not mistaken. I have one on my 4R70w, as it was pointed out as a weak link when I rebuilt mine.

I don't know if an AOD is like a 4R70w w/ regard to lock up, but I was under the impression that downshifting while in L/U is what breaks the input shaft. Do you have a manual VB conversion on a later model AOD, or are you using one of the earlier non-electric models?

 

[A5literMan]

You're entire topend is limited. 302 parts=302 power. That's why there is a big drop off in power. Not a good setup for a 351w if you want good power.

My recommendations (I love spending other people's money) for maximum power are- a 90mm maf,3 1/2-4" power pipe,90mm throttle body,TFS R box intake,205cc 11r heads,a custom cam,1 3/4- 1 7/8" long tube headers and at least a 2 1/2" exhaust system. With that combo you should see an additional 100rwhp/50+rwtq improvement and at least 1- 1 1/2 sec 1/4 mile improvement.

Now if you're just going to keep those heads and intake, at least contact a custom cam provider and get a new cam,springs,etc. Have the intake ported and get a port matched tb on it. You also would probably benefit from a dyno tuned chip/stand alone ecu at that point but it's not entirely necessary. Stock electronics will keep up but you'll be leaving some improvements off the board,such as idle,part throttle response,and maximum power production.

 

[Stang_1973]

Wow i didnt think the RPM heads were lacking so much. IDK why i figured them to be on par with AFR 185s. Well i got this entire motor from a guy who was giving up on a restomod project himself. he already had everything together which is why i used it all.

the AOD, has a Lentech valvebody which basically retunes the AOD since its non-electronic. it give you a bit more control to drive it manually, and higher line pressure so you dont burn it up.

So basically bigger TB, better intake, better heads if possible, and better cam. LOL. all the goodies.

 

[Stang_1973]

Wow i didnt think the RPM heads were lacking so much. IDK why i figured them to be on par with AFR 185s. Well i got this entire motor from a guy who was giving up on a restomod project himself. he already had everything together which is why i used it all.

the AOD, has a Lentech valvebody which basically retunes the AOD since its non-electronic. it give you a bit more control to drive it manually, and higher line pressure so you dont burn it up.

So basically bigger TB, better intake, better heads if possible, and better cam. LOL. all the goodies.

 

[A5literMan]

Wow i didnt think the RPM heads were lacking so much. IDK why i figured them to be on par with AFR 185s. Well i got this entire motor from a guy who was giving up on a restomod project himself. he already had everything together which is why i used it all.

the AOD, has a Lentech valvebody which basically retunes the AOD since its non-electronic. it give you a bit more control to drive it manually, and higher line pressure so you dont burn it up.

So basically bigger TB, better intake, better heads if possible, and better cam. LOL. all the goodies.

Yep

 

[autopart101]

I have a TFS 351 LR EFI intake and Holly 80mm TB I would sell you cheap with the fuel rails.