Hey all, I have mixed feelings about what trans to hook to a new motor I just bought. Help me out, especially if you have been there, done that. The short of it is this: 347 Canfield 195 heads forged flat top probe pistons forged I beam rods steel crank custom jay allen billet hydraulic roller cam (matching package to heads) 10.8 compression trickflow 1.6 roller rockers I have 2 ways to go with this motor, currently it has an edelbrock rpm II intake, fuel rails, injectors, everything need for complete EFI setup. I may stick with carb and put a victor jr intake and 750cfm on it for now (quicker), possibly convert to efi later, havent decided yet. Either way, for ease of money and installation, I planned to stick with an overdrive auto, probably AOD. the engine was orig. deisgned/spec'd for a 5 spd (tremec/tko) and 3.7.3 gears for top performance. Am I crazy for considering an auto with this setup? I would imagine it needs at least a 2500 stall, so will that kill mpg when cruising below that RPM because it isnt locking up? Would I lose signifigant power vs. a manual? Can and AOD handle this? It wont be a racecar, just a weekend toy with a little showing out here and there. Thanks!
I suggest you stop by www.clickclickracing.com Silverfox and the gang are the AOD experts and will be glad to help you out.
Lentech up in the great white north has fine products that will fill the bill. Not exactly what I would call cheap, but good value. When I called, we discussed the exact application in quite a bit of detail; as a result, the transmission and converter were very compatible with the rest of the setup and worked really well.
I had almost the exact same setup in my 67 Mustang. I ran a C-5 yrans, from an 81 F-100, built up, 3500 stall.
I built a 65 Mustang for a guy with a similar 347 and a Lentech AOD. Handled the power no problem. Ran some stout gears (3.70) and a 2800 stall, still got 25 MPG on the highway
I was looking at the lentech, they seem pretty stout. Only downside is the cost, I could go either way at that point, tremec 5 spd or lentech auto. Those tremec/tko setups are $1200 and up too.
Frankly I don't think it will really make any damn difference, just a matter of personal preference... do you want to bang gears in this particular car or not? Just have to build whichever drivetrain you choose to "fit" the package. IMO your engine package will be about 450 HP + or - about 25 HP.... (probably more like -25) My son is running a VERY SIMILAR 408 SBF, his is likely close to 500HP and no more... I don't know what the numbers are on your cam, but my son's numbers are at the upper limit for a REASONABLE street driven cam,... My 408 wilol be very similar as well, and will be about 450HP... TKO or AOD no Problem.
ok check this out, I own a shop and I do ******s(along with everything else) and I have a 65 Mustang on my lift right now almost the same setup. 347 trick flow heads all the go fast stuff. car dyno'd @ 340 at rear wheels. the guy is running a C4 and he keeps tearing up the band and intermed drum. 3 transmissions later and after talking with Turbo Action, TCI, and B&M. I have found the only trans they could reccomend for severe use-drag-big motor-nos- C6. If you take a C6 and C4 aprt you can visually see the parts are way bigger. I'm no ford guy by any means but the C6 is about as indestructable as the GM 400. Just my opinion based on alot of research for a customer.
something is wrong,,, a well built c4 should be able to take 400hp in a light little Mustang just fine... Neutral drops?
There are performance C4's made for this (so i hear), such as performance automatic's c4, some of which are rated up to 800HP. They take them and rebuild them with the beefier parts and have heard good things about them. But take that stock c4 price and add about $800 to it. On the C6, some will bolt up to a small block, and some will not, right? I know they can take some abuse, since they mostly sit behind the big blocks, but not sure how easy it is to come by a SBF c6. Are some made to go behind small blocks, or are they adapted to do so? The issue here, stock c4, very affordable...reliable for this motor? dunno....well built c4 puts you in the price range of a tko/tremec or even a lentech aod ("well built"). I was hoping to find a good fit ****** for lower cost, but it appears I will have to pay to play with this engine setup. 39allford, to answer the question though, if they all cost $1200, I am going with a 5 speed, tko 500 or tremec 3550...I personally know people with much more HP than me using them, and you just cant kill the things. I can bang gears and get damn good mileage cruising. BUT, if I could save 400-500 dollars using something else (C4/C6), I would do it and upgrade later if need be. The beauty of it all, the engine builder that did much of the work on this motor said his friend has a near identical engine as this one, and averages 20mpg on the highway in his tbird with a tko 500 behind it. but DA@^#% they are proud of them
The C4's have a detachable bellhousing and the C6's are cast in 1 piece and only will fit the motor they were made for. The C6/small block transmissions are kinda rare. The C6's take away more HP from the motor than a C4 does. Correct: A well built C4 even stands up to a built big block as long as you only use an 8" tire MAX. Get a C4 from a pickup. The bellhousing is held on by it's own bolts instead of the car type, which uses the front pump bolts to secure the bell.
Hmmm......what car is this going into (weight) ? Rear end size and gear ? Tire size ? These are all things to consider when choosing a trans.
I agree with most of this. Look in 80-84 F150's/250's for the C6 small bell trans. Not sure if C4 pickups are the difference. I just know of pan fill and case fill. The pan fill is the type that has 5 bolts around the outside of the pump. Simply crawl underneath and look to where the dipstick tube goes into the trans.....case or pan. (case fill has 7 bolts that go into the pump) And be aware of the C5.
The later C-4's had a case mount bell while the early C-4's used a pump mount bell. Early (up to 1970) C-4's used a 24t input, 1970 up used a stronger 26t input. Some C-4's had a pan fill, most were case fill C-4's had 157t flywheels and 164t flywheels. Bellhousings must match the flywheels. I ran a C-4 behind a mild 393 stroker for years, only modifications were the "H" servo and a B&M shift kit. Don't know beans about an AOD or C6, sorry.
That motor will be hard on a stock C4 or AOD. There seems to be a big price difference between the performance built C4s and AODs. The AODs are more money, but if you can afford it, I would recommend it. That extra gas milage and lower 1st gear are nice.
The other thing is the HP loss between them too. Supposedly around 60hp loss on a c6 and around 30 on a c4, then the 50 pounds extra weight of c6.... i found a c6 small block locally for $75, needs a rebuild. Its going in a 56 customline, somewheres around 3200 pounds i think. Have to change the rear, currently an 8" with 2.79. Planning an 8.8 explorer swap with 3.73 trac lock. 15 inch wheels.
I would use a C6 or an AOD in your set up, prolly an aod if yer going with a 3.73 gear and 15 inch wheels......it would be a highway Happy car with an AOD.
If it's not a street/drag car... overdrive it. Otherwise a decent c4 can handle a LOT of 8 sec. p***es and street time
My original plan all along was AOD, until the engine builder basically said that was the worse thing I could do for that motor. But, I do recall him saying a friend of his had essentially the same engine (just different cam), used an aod (tbird) and was running 11.9's and 12.1 at 1/4 mile regularly. He talked him into switching to the 5 speed tremec and knocked off 1/2-3/4 sec every p*** since. That is not what my car is for. So, I was thinking, how can the aod be that bad then, I am not looking for the best 1/4 mile time here... I am looking for good, reliable mileage, but also good get up and go. Do I have to worry about the stall using an AOD? If its 2500 stall, cruising at 60 down the highway in overdrive, i wont be anywhere near that, thus the converter not locking up. Poor mileage, loss of power?
the lock-up converter and two piece input shaft are what to worry about. A built AOD will be strong. If you decide on the 3.73 Explorer rear, you will likely need the OD anyway. I also recommend clickclickracing.com. Silverfox knows these trannies really well. I joined up a while ago, and the info is good.
The C4 if built right is a great trans and will hold up very well for the engine you have plus ! Some will use an AOD if they drive on the street . I would use a C4 with trans brake any day ! As for the 2500 stall , I would go with a higher stall to race with ! The C6 is also a good Ford trans too ! I would still go with a C 4 ! Just my 2 cent !
Ok, so lets talk about "built right". Everyone mentions that, but not really what it means. Are you buying a kit, picking parts yourself, have a local shop beef it up? How much $$ does it take to make a C4 "right"? I like the AOD or 5 spd just because I live 35 miles out of the city. So when I go cruising I got a ways to go to and from.
A stock AOD uses a 2 piece input shaft that byp***es the torque converter in 3rd and OD, so no worries about high stall slippage at cruise. It is a weak point though, and a heavy duty build will use a 1 piece shaft so stall speed becomes an issue again. Another option is the AODE/4R70W. It is an update of the AOD which uses a 1 piece input and a converter with a clutch. It is electronically controlled however, so would need a stand alone controller, which adds cost, but allows custom tuning of the shifts and lockup, or push****on shifting. I don't think you are going to find a cheap overdrive that can reliably handle some power and abuse. This is going to be a pay to play situation.
If you are looking for C4 build info here is some reading material; http://www.fordmuscle.com/forums/c4...-c4-thread-text-edited-way-long-version2.html
It definitely looks like a pay to play deal. Thats what I wanted to know, and it seems to be the case. Just have to convince the wife now
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