Turbo, or revs?

"DeWayneV8" (squirmish)
05/20/2015 at 09:01 • Filed to: None

I’ve been contemplating an upgrade to the power level of my fox body for awhile now. The engine in it is a stock 4.6 3V from a 2009 Mustang, and I’m struggling between adding a turbo or porting the heads and installing bigger cams. I really like the noise and response of the engine right now, and keeping it NA probably makes more sense for Autocrossing.

The engine makes 300 rwhp now, and in my experience 440-450 rwhp is reliable with a turbo on a stock engine. The car only weighs 2890, and that sort of power to weight is tempting! Heads/cams would be good for something like 370-380 rwhp....but DAT NOISE. It would also be much easier to install, and require no changes or cooling upgrades.

Whaddya think?

DISCUSSION (67)

Smallbear wants a modern Syclone, local Maple Leafs spammer > DeWayneV8
05/20/2015 at 09:05

LS swap. :)

crowmolly > DeWayneV8
05/20/2015 at 09:05

Head/cam.

I’d go turbo when you’ve got the cash to do it right. No sense in throwing a turbo on a 4.6 with a 10:1 compression ratio and no supporting gear.

LongbowMkII > DeWayneV8
05/20/2015 at 09:06

N/A is best. are the 3v mods SOHC or DOHC?

DoYouEvenShift > DeWayneV8
05/20/2015 at 09:09

FI FTW! Do they TVS blowers for that thing?

DeWayneV8 > crowmolly
05/20/2015 at 09:10

Well if I did a turbo, I’d build the system myself and set it up so that when I eventually built the short block I could turn it up a bit.

4.6 3V’s are 9.6:1 compression, to be honest I wouldn’t go lower than that with a turbo setup. I don’t want it to be a dog off boost.

DeWayneV8 > LongbowMkII
05/20/2015 at 09:11

SOHC. It’s not that expensive to do cams on them compared with say, a coyote. They also respond REALLY well to cams, I’ve seen 50 rwhp from just a cam swap. That’s a large increase percentage wise.

DeWayneV8 > Smallbear wants a modern Syclone, local Maple Leafs spammer
05/20/2015 at 09:13

I figured someone would post this.....and I’ll respond by saying the fastest mod motor in the world is faster than the the fastest LS at the dragstrip, and it’s only 4.6L!

DeWayneV8 > DoYouEvenShift
05/20/2015 at 09:15

Edelbrock and Saleen both make nice TVS setups....they’re pricey though.

crowmolly > DeWayneV8
05/20/2015 at 09:19

Well, how much boost do you think you could run on the stock bottom end? How about the fuel system?

Bob Loblaw Made Me Make a Phoney Phone Call to Edward Rooney > DeWayneV8
05/20/2015 at 09:23

Turbo. A solid N/A build is just way too much work on a 3V. There are some dudes running pretty healthy N/A 3Vs in NASA, but those are pretty-high strung motors with a lot of money in them. That motor likes to breathe, and while it will need some bottom-end work to put real power down, you can have a safe 400 to the wheels without being scared shitless of when it’s going to let loose.

Rusty Vandura - www.tinyurl.com/keepoppo > DeWayneV8
05/20/2015 at 09:23

Turbo seems more elegant .

DeWayneV8 > crowmolly
05/20/2015 at 09:26

It already has a good fuel system in it, I’d just have to do an injector upgrade. Easy Peasy. I’d probably run 7-8 psi to keep it safe, but there are guys going 9’s on stock block 3V’s with turbos.

Sethersm > DeWayneV8
05/20/2015 at 09:26

Kinja'd!!!

It seems the car has a preference.

DeWayneV8 > Bob Loblaw Made Me Make a Phoney Phone Call to Edward Rooney
05/20/2015 at 09:30

I mean I’ve built 3V’s that make 500 rwhp NA, but that does require some special work. For 4k I could build an NA motor that would make 400 rwhp, and that would include short block upgrades (rods and pistons). To build a turbo setup correctly and do the necessary cooling upgrades would be as much, but you’re right it would make more power.

DeWayneV8 > Sethersm
05/20/2015 at 09:31

You sir, win.

MontegoMan562 is a Capri RS Owner > DeWayneV8
05/20/2015 at 09:31

I have a recommendation and a question.

Recommendation: Cam/Heads. Hand’s down this is your first step. If you feel later that you still aren’t making enough power - THEN do a turbo.

Question: What motivated you to remove the 5.0 and drop in a 4.6? Was it originally a V6/I4 car and wanted an upgrade? I don’t think I’ve ever seen someone go out of their way to drop a 4.6 into a Foxbody/Notchback. Just curious, not hating. (I’m a 5.0 owner - my 68 Montego)

DeWayneV8 > Rusty Vandura - www.tinyurl.com/keepoppo
05/20/2015 at 09:32

It sort of does, and it would be so damn fast. choo-choo.

Opposite Locksmith > DeWayneV8
05/20/2015 at 09:37

Turbo! More power and if you maintain the cr and boost it conservatively like you’ve said in your other comments it will still be auto x and street friendly in terms of power delivery. Cammy motors can be just as tricky as crazy boosted engines anyway

DeWayneV8 > MontegoMan562 is a Capri RS Owner
05/20/2015 at 09:38

The reason is easy, cost and reliability. I got this engine with 36,000 miles on it delivered to my door for less than $1500. That was complete with manifold, injectors, wire harness, even the alternator. Ford racing sells a really nice ECU conversion kit that’s about $1200, and so I have drive by wire throttle, full OBD-II, a CAN bus that allows for digital dashes and easy datalogging, and the option for cruise control and traction control.

No 5.0 will ever have the sort of reliability this setup has, and the weight benefit is nice. So for around $3k I’ve got a 350 hp all-aluminum V8 that has OE reliability and race quality ECU capabilities.

Sweet Trav > DeWayneV8
05/20/2015 at 09:40

My advice is turbo or blower. The mod motor has some pretty small bores to make it an effective high rpm screamer, something I have lamented many many times. (stupid Ford and their packaging requirements causing the engine to have too small of a bore spacing to hog out the holes, similar reason why the northstar sucked) the 03 cobra should be enough to tell you that these engines love boost. If you had an LS motor I’d tell you to De-stroke it and make a modern 302dz, but since you have the mod motor already, shove some boost down it.

I’m practically down the street if you want a hand.

DeWayneV8 > Opposite Locksmith
05/20/2015 at 09:43

Yea I would do a relatively small turbo, I’m not a fan of waiting till 3500-4000 for full boost. I’d do a mappable electronic wastegate controller so that I could reach peak boost faster too.

DeWayneV8 > Sweet Trav
05/20/2015 at 09:48

You’d actually be surprised, you can make more horsepower and rev them higher than you think. By modern standards, the mod motor has huge bores. It’s really uncommon for any modern engine to have bores over 90mm. 3V heads can flow 300 cfm on the intake side with stock bore size if ported correctly.

If I did the FI route, I’d do turbo. It gives me a good excuse to break out the TIG welder, and the good blowers are expensive. I know centrifugals can be had at a reasonable price, but I hate centrifugals.

DeWayneV8 > Sweet Trav
05/20/2015 at 09:52

Also, we should grab a beer and wrench on our cars sometime. Is your car carbureted? I’m pretty handy at tuning those things.

03mach1 - Now has a Fiesta ST > DeWayneV8
05/20/2015 at 09:56

Personally I would port the heads and get new cams. I just prefer an NA set up over a turbo, though I could see a turbocharged fox body being lots of fun. Plus you save from gaining weight with a turbo. Either way you can’t really go wrong.

Would the cams give you a lopey idle? My dad got the Ford Racing Track Cal tune on his '14 5.0 which enables the lopey idle like the Boss. It is awesome, the car even shakes like a classic muscle car. That would be another reason to install new cams.

By the way, that’s a great looking fox body! A notchback as well. What do you have done to it?

Opposite Locksmith > DeWayneV8
05/20/2015 at 09:57

Music to my ears. Do this haha

Sweet Trav > DeWayneV8
05/20/2015 at 09:58

Yeah, I just ordered the spring loaded needle seats and a fuel pressure gauge from summit to evaluate the stumbling and stalling in hard corners. Might be float level adjustment. I could use a hand with that. Any plans for Memorial Day weekend?

DeWayneV8 > 03mach1 - Now has a Fiesta ST
05/20/2015 at 10:02

Thanks for the kind words! It’s got the 4.6 swap, a 3650 trans from a 2001 Mustang, Mach 1 brakes all around, MM Torque arm rear suspension, coil overs in the front, a cage, and a bunch of chassis stiffening. It’s still sort of a work in progress, it’ll get there!

The weight is a big disadvantage with the turbo, and it’s all on the nose. The cam swap would make the idle quite lopey, with drive by wire you can get them to idle real low and have that “brrap brrap” idle sound. Definitely a bonus.

Sweet Trav > DeWayneV8
05/20/2015 at 10:02

Don’t blame you, I hate CF blowers too. Roots or turbo for FI.

Yeah, but mod motors are so pricy to build for revvs. Plus, I’m of the opinion that if you can’t get it done between 2000-7000 you need different gearing. I also recall mod motors being limited to relatively small lift for cam choice, could be wrong. Plus with FI you get nice happy drivability, and power when you want it. You may have to look for a vacuum pump for your brakes though.

DeWayneV8 > Opposite Locksmith
05/20/2015 at 10:03

choo-choo.

DoYouEvenShift > DeWayneV8
05/20/2015 at 10:05

They are pricey. Nice setups though. Maybe find a used one.

DeWayneV8 > Sweet Trav
05/20/2015 at 10:08

It’s got hydroboost anyway, I’ve upgraded the braking system to a full Mach 1 setup. No vacuum worries here! To be honest the main thing holding me back from doing the turbo is the sound. The car just sounds so good.

I’d guess that float level is your problem, you may need some jet extensions too. They sell road race style jet extensions that sort of look like vacuum nozzles so that it sucks the fuel from the bottom of the bowl.

Unfortunately I’m heading back to Chicago for the weekend to see my folks, but next week we could do some tuning on that beast. Do you have a wideband?

DeWayneV8 > DoYouEvenShift
05/20/2015 at 10:10

Yea that saleen blower is REALLY efficient. I’ve seen it make 440 to the wheels on like 6-7 psi of boost. Very safe.

03mach1 - Now has a Fiesta ST > DeWayneV8
05/20/2015 at 10:12

That sounds like such a fun car to drive. I want a fox body so bad! To bad they’re hard to find in decent shape lately. Around here 6K could have bought you a really beat up one with lots of work needed. That said I can’t complain with what I ended up with....

Keep us updated on the build, I look forward to seeing what you do!

DoYouEvenShift > DeWayneV8
05/20/2015 at 10:14

That may be true. But on the streets and for the packaging, dollar per hp, availability, reliability, simplicity. You wont beat an LS.

Want to rev? LS7 block, 4.8 crank. Comes out to 5.7 I think. Nice heads and intake. High rpm power, gets expensive though.

DeWayneV8 > 03mach1 - Now has a Fiesta ST
05/20/2015 at 10:21

It is fun to drive....you forget how small and light fox bodies are until you drive one!

The prices of these things are skyrocketing, mine needed lots of work when I got it.

Kinja'd!!!

I had to replace ALOT of the metal in the car

Kinja'd!!!

DoYouEvenShift > DeWayneV8
05/20/2015 at 10:25

Oh yeah, I love TVS blowers. Look how good the eaton GT500s respond to them. Sucks they’re so expensive, but they are good. Im planning on getting a C5 soon, I may throw one on there.

SnapUndersteer, Italian Spiderman > DeWayneV8
05/20/2015 at 10:25

Get a real engine, the engine from a Suzuki Every Joy Pop Turbo

Kinja'd!!!

that is the car that is the best ever made

DeWayneV8 > DoYouEvenShift
05/20/2015 at 10:25

I don’t disagree, I was just busting your balls in return for you busting mine! LS engines are absolutely the way to go in terms of power per dollar. They’re light too.

It’s fun doing something different, can’t be too many notches out there with a 3V.

DeWayneV8 > SnapUndersteer, Italian Spiderman
05/20/2015 at 10:27

I’m not sure my chassis can handle all of that awesome.

DoYouEvenShift > DeWayneV8
05/20/2015 at 10:28

Haha, no biggie. Ive seen many Foxes with LS swaps. Never a 3V, so that is different. Mod motors do respond to boost well though.

MontegoMan562 is a Capri RS Owner > DeWayneV8
05/20/2015 at 10:28

Well, a coyote 5.0 would have all those things lol.

But it sounds like for your needs it’s doing what it should. I’ve never really been a mod motor guy, but 350hp out of a reliable lightweight V8 is a good deal.

I do love my old windsor 5.0 though.

DeWayneV8 > MontegoMan562 is a Capri RS Owner
05/20/2015 at 10:31

I considered a Coyote, but they are quite pricey to swap still. Even if you shop around for a used engine and really find good deals you’re looking at 8k all in. When they come down a bit in price they’ll be the way to go for sure....but I’ve only got about 14k in the entire car including cage, paint, and original purchase price. I couldn’t justify 8k on just the engine for a budget build like that!

crowmolly > DeWayneV8
05/20/2015 at 10:33

Well, that changes things.

What cooling upgrades would you need?

MontegoMan562 is a Capri RS Owner > DeWayneV8
05/20/2015 at 10:44

oh no way, I was just making a joke that you could do that with a 5.0......just not a windsor 5.0 it would have to be coyote.

Those things cost a fortune still. Awesome motors, but with a big price tag.

Sweet Trav > DeWayneV8
05/20/2015 at 10:46

No wide band, and edelbrock/carters have jets in the bottom of the bowl, no need for extensions. I’m also concerned about the pump overpowering the needle seats. So I got a gauge for the carb feed line

DeWayneV8 > crowmolly
05/20/2015 at 10:47

It would need a radiator with more cooling capacity if I went turbo, and I’d probably want to upgrade the oil cooler as well. It has an oil cooler, but with the turbo the oil gets so much hotter that I’d want a bigger one.

crowmolly > DeWayneV8
05/20/2015 at 10:50

Doesn’t sound like too big a deal then. Flip a coin. LOL.

DeWayneV8 > Sweet Trav
05/20/2015 at 10:51

Yea, definitely need to make sure it’s only getting 6 psi over the whole RPM range.

Do yourself a favor and get a wideband, preferably one that has some kind of datalogging capability. I can show you how to do it with an arduino for CHEAP. You will thank yourself 1,000,000 times over.

DeWayneV8 > crowmolly
05/20/2015 at 10:53

I guess it’s just going to come down to whether or not I want to take the engine out.

crowmolly > DeWayneV8
05/20/2015 at 11:01

If it’s still pretty fresh I don’t know if it would be worth it.

TJDMAX > DeWayneV8
05/20/2015 at 11:07

As simple as it sounds I would go with the upgrade that gives you the best midrange power. For Autocrossing you want the most usable power. So if a turbo is going to take too long to spool it wouldn’t be a good idea. On the other hand if a cam and head upgrade caused the motor to make power way high in the rpm range then it would also not be ideal. So i would figure out what would get you the most usable power and go from there.

Sweet Trav > DeWayneV8
05/20/2015 at 11:14

You sound like the guy to help me with an LS swap down the road...

Kanaric > DeWayneV8
05/20/2015 at 11:24

Why not supercharge?

DeWayneV8 > Sweet Trav
05/20/2015 at 11:26

Hell yes, let’s put an LS in that boat right after we get done putting a corvette chassis underneath it!

DeWayneV8 > TJDMAX
05/20/2015 at 11:28

I could setup the turbo to spool quickly, but I’m honestly worried it would have too much midrange with a turbo. I guess I could always gear the car down if that happens.

DeWayneV8 > Kanaric
05/20/2015 at 11:32

A centrifugal is useless in autocross, and the TVS or screw blowers are really expensive. It’s like 6k for a saleen or edelbrock setup, which is what I’d prefer.

AthomSfere > DeWayneV8
05/20/2015 at 11:44

Keep it NA!

Sweet Trav > DeWayneV8
05/20/2015 at 12:00

I’m thinking of something slightly more sedate

http://m.summitracing.com/parts/upi-gbf0…

DeWayneV8 > AthomSfere
05/20/2015 at 12:05

DAT V8 NOISE

DeWayneV8 > Sweet Trav
05/20/2015 at 12:12

That looks like a really nice setup! Have you checked out detroit speed’s stuff? I’ve used their stuff on a G-body before, worked well. That kit you posted looks really nice and complete, what is it about making shitty muscle cars go around corners that’s fun??!?

AthomSfere > DeWayneV8
05/20/2015 at 12:15

And smoother curves... I love a good BOV sound from FI too, but a big bad v8 makes sexy noises!

TJDMAX > DeWayneV8
05/20/2015 at 13:08

I don’t autocross but i gather that half the fun is tuning / adjusting the car constantly to eek out the quicker times no? Increased power is always going to cause a different “issue”. Traction, or gearing, or durability of components, etc. Whichever path you take i’m sure you will have a fun ass car and enjoy autocrossing it.

If i had to give my opinion though I would go with keeping the motor N/A. Turbo’s even if set up right still cause excess heat and after a lot of sequential runs could lose effective power due to heat soak issues. It doesn’t seem that the car ever really gets up to a fast enough speed to offer significant cooling so an intercooler wouldn’t be a hugely beneficial tool in this situation.

But you probably know better than me.

DeWayneV8 > TJDMAX
05/20/2015 at 13:15

I think the main benefit of the NA setup would be better throttle control.

On the intercooler side, I’d do an air to water setup for that very reason. Being able to cycle the water between runs would be a huge benefit too.

The main problem with a powerful rear wheel drive vehicle in autocross is that generally you need a lot of roll stiffness and sidewall stiffness to be fast in transitions, but that makes traction bad which screws you on the launch and coming out of low speed turns.

I’m leaning more towards the NA route, partly because no one would expect an NA 4.6 to be fast!

TJDMAX > DeWayneV8
05/20/2015 at 13:19

Yea seems like a situation where too much power could be bad. More important to be able to use all your power and get it to the ground as quickly as possible.

SnapUndersteer, Italian Spiderman > DeWayneV8
05/20/2015 at 15:01

I know you can’t!

Justino6969 > DeWayneV8
05/21/2015 at 21:02

Turbro, bo.

DeWayneV8 > Justino6969
05/22/2015 at 20:01

TURBO ALL THE THINGS