Hello, longtime lurker, first time poster. (You offroad forum guys know me)

I'm planning on doing something waaaaay different as far as engine mods go. First a little background. I have a truck that I'm getting rid of so I can dedicate more time and money to my hotrod. It's a 73 F100 2wd longbox. About 11 years ago I went from the tired 302/t18 to a 390/C6. That got boring pretty quick so I upgraded again shortly after to a 460/C6. Well, the time has come again to upgrade engines and I'm looking to do something different.

I want to build a 521. Not just any 521, but something special. I want to stay "small" due to block strength (.030" overbore). I haven't figuerd out which turbochargers to use yet, but there will be at least 2 of them. I'm having trouble finding 2 that will be the right size because not many 260-inch engines came with them. I was originally thinking about using four 2.2L Chrysler turbos because low-mileage turbos are everywhere for these. (2.2L Dodge engines had problems and didn't care for added cylinder pressures) The reason for the small turbos is because of my cam choice (read below).

I was planning on Scat crank/rods, forged pistons (duh), and 670 CFM Holley pro-jection (since that's been on there since '95).
So if I use D3 heads, grind the flow restrictor out of the exhaust ports (you know what I'm talking about), and use a Crane 359331 roller cam, how would I be looking? Could I run 8.5:1 and still run 8 PSI streetably? The specs for this cam are very conservative and will give me great low-end up to about 4500 where everything drops off.

Desktop Dyno 2K says 650/TQ @2-2.5K and 492 HP @ 4500 naturally aspirated. That's why I want the small turbos......this thing will be a low-end rocket (If I could get any traction) I can't see running anything larger than a 670 CFM t-body because of that either.

Anybody see any problems with this besides the small amount of intake flow? About the only other thing I may have problems with is oil pressure due to 4 turbos dropping volume. That's easily remedied with an aux. pump.

Cody

 

An interesting combination.

My main thought is that the four wheezers will be a nightmare to plumb. I would probably prefer to use 2 bigger turbos & 'gates; possibly a very small momentary shot of nitrous to get the turbos spooled up.

Might want to look at an E4OD or a Gear Vendors unit, too.

 

man cleatus, you just described my ideas to the letter for my 460 in my 76 2wd F-150....im drooling over the thought of twin turbos........"low end rocket" lol, i might have to paint that on my truck if ever actually do that mod!!! im with you on the traction part, my stock 460 already has too much gumption for my 9" rear and springy leaf springs, as soon as i hit the gas im practically sideways most of the time......only cure i can think of is ladder bars, limited slip, sticky slicks, and half of a chevy in the bed!!!!! let me know about any turbo tech you come up with for these 460's.......

 

SwOKC...,

A great general source of turbo information can be found here: http://www.turbomustangs.com

About everything you need to know to begin can be found there, if you look. Do some searches first; they tend to snarl at people who want a "free ride" (answers to everything without doing any work), so to speak.

They also have some specific 460 posts too; although the principles are the same no matter what you drive.

 

Yeah, Homespun91, I hear ya. What a nightmare to plumb all of those hoses. As far as wastegates go, I was actually planning on hooking up a microswitch to the throttle and using that to run a relay that would actuate solenoids on the wastegates. That way, as long as I was at less than, let's say, 1/2 throttle, the wastegates would be open and little boost and restriction would be created. Once 1/2 throttle is reached, the switch would be closed and the wastegates would close. Run the ground side of the relay to a pressure switch that opens at maybe 6-8 PSI......would have to work out "surge" issues though if I did that.
The reason I want small turbos is the quick spool-up. I've run nitrous quite a bit in the 460 and it's cool and all, but I don't know if I want to use it again.
I did have plans to go with an E40D later on down the road, too. Beaumann (sp?) makes an E4OD stand alone computer, but I'm not sure that I can afford that right at the moment. Ford should've made a better AOD that they could have put behind a 385 series. A gear vendors unit is expensive but I doubt I'd ever have any troubles with one. I'm going to put 2.75 gears back in it once I get the engine done.

SWOKC, I do have traction issues right now too!! I'm running 295/50's all the way around, 3.25 gears, 3-link rear suspension w/airbags, and a heavy right foot. With the N2O I could take off in second gear and once I hit 2000 RPM, hit the button and just FRY the tires. It was cool because I was running a spool at the time and the truck would just go sideways.

I've got a lot of planning to do, but when I know what I'm doing I'll let you know.

Cody