Stage IV to Whipple swap with basically stock fuel system?

I'm tossing around the idea of getting rid of my Steig IV ported blower and replacing it with a 2.3 Whipple and doing a "low boost" setup (13-14psi). What kind of numbers can you get with a lower boost setup on the Whipple with stock MAF, injectors and a BAP?

Yes Whipple is alot better than a Steig IV. Whipple you can get around 600rwhp and the steig I think is 450-500rwhp. Go ahead and use that money you are saving on injectors and the MAF for a new bottom end since it will not last long without them. Going lean will kill your engine.

If you dont up the boost, Whipple says that you can run the 2.3 on the stock fuel system and tune. Whipple also says just the blower swap, leaving everything else stock will gain 85hp. I have not heard of anyone doing that, but that is how Whipple advertises its product. FWIW.

Considering I ran out of injector at 490whp and the MAF was gone before that, I'd recommend spending the extra cash.

Last thing you want is a 12K boat anchor

With the ported Eaton or the twin screw, you will have to increase your fuel availabilty situation through either a BAP or GT fuel pumps. You've already done the BAP.......

With the twin screw at 13 lbs of boost and up, and some Ported Eaton setups, you will need to upgrade your fuel injectors The factory 39 lb injectors are generally sufficient to 540+/- RWHP.

I'm surprised your MAF system is still satisfactory with your ported Eaton setup......Mine pegged with just an unported upper/lower combo. But although there are tuning strategies out there that can tune for high horsepower without increasing the MAF capacity, most of the reputable tuners use the MAF system extensively to maximize their tunes. And adding a Mafia is as simple as it gets. Just plug and play.

My MAF had room....but it was getting up there. I dynoed in 60 degree weather, and really don't take it out in temperature less than that due to traction difficulties. I actually didn't need the BAP either, but turned the dial up anyway since it was installed prior to the tune. My tuner said that folks can peg the MAF to a certain degree without problems (I was NOT pegged); sometimes at 5500 rpm with no affect on the A/F ratio which is what you are really interested in.

Consider 60lb injectors and a MAF to be a 'must' when going with a twin screw set up (and even a port IMO).

I don't think too many guys take the risk and skimp out on getting them being that about $650 for injectors and a MAF is a lot less than the 3K+ for a new motor.

It's highly unlikely that you'll get by with the stock MAF and injectors when going to a twin screw set up. They absolutely will need to be upgraded. I'd strongly advise against doing the swap if you don't plan on upgrading the injectors and MAF.

I'm considering a "low boost" setup (13-14 psi) with the twin screw on the stock fuel system with BAP. How far can you go on a Whipple on the stock fuel system in terms of boost? I wasn't considering doing the usual 17-18 psi with Whipple.

NFCstang said:

Last thing you want is a 12K boat anchor

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:lol:

liedenfrost said:

I'm considering a "low boost" setup (13-14 psi) with the twin screw on the stock fuel system with BAP. How far can you go on a Whipple on the stock fuel system in terms of boost? I wasn't considering doing the usual 17-18 psi with Whipple.

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Dude,

Spend the money and get the injectors. It's an extra $500 worth of insurance.

As I said before and as other people will attest if you search, many people have run out of injector at less then 500whp. YOu hook up a Whipple even at low boost with stock injectors and you're taking a real chance.

Steig blower then trying to get by with a "very conservative" (cheap) Whipple tune you're probably going to make close to the same hp with the Whipple. Now why spend $2800+ to do that? It doesn't seem to smart of an idea:shrug:.

posi said:

Steig blower then trying to get by with a "very conservative" (cheap) Whipple tune you're probably going to make close to the same hp with the Whipple. Now why spend $2800+ to do that? It doesn't seem to smart of an idea:shrug:.

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You will make more power with the Whipple per/psi of boost. My question I was trying to get answered:
How much power can you get out of a Whipple vs Eaton on the stock fuel system?
We know we can get about 500 rwhp/500 tq on the stock parts with an Eaton. We should be able to get more than 500 rwhp/tq with a Whipple with the same stock parts due to the greater efficiency of the blower. How much more...I don't know and was curious to see if anyone knows.
Folks spend about $4000 (new clutch, 60's, MAF, cooling, etc to go from an Eaton to a Whipple and gain 100 hp; It might not be a bad idea if you could pick up 40 hp or so by just replacing the Eaton with a Whipple. Whipple advertises 85 hp and 40 -50 tq by just replacing the Eaton.:shrug:

i see where the confusion is now. even with the same amount of boost, you are moving a greater amount of air with the Whipple. this in turn increases the duty of the injectors and pumps. more than likely they will max out. even though boost is the same, power and total air/fuel used increase. this means your pumps, injectors, and MAF will need to work harder.

99riocobra said:

i see where the confusion is now. even with the same amount of boost, you are moving a greater amount of air with the Whipple. this in turn increases the duty of the injectors and pumps. more than likely they will max out. even though boost is the same, power and total air/fuel used increase. this means your pumps, injectors, and MAF will need to work harder.

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That's why I was saying he's going to need a "very" conservative tune to get it to work. So then the power levels would be similar as he should have now. Maybe another 30hp but that's not worth it.


If you wanna play you gotta pay! Just don't forget that rule.

With the possible exception of fuel injectors, (and maybe throttle body if you go twin screw with single blade), you willl need the exact same auxilliary mods for an aggressive Eaton setup as you will with a mild twin screw setup. This includes MAF, Fuel delivery upgrade, clutch system, and tires.......

My current Eaton setup is such that if I were to go twin screw, the only chnages i would need are the blower itself and a revised tune.

IronTerp said:

if I were to go twin screw, the only chnages i would need are the blower itself and a revised tune.

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Twinscrew? Twinscrew? Did I hear somebody is looking for a twinscrew:dw:?:rollseyes

i went from 514rwhp to 579rwhp with a 2.3 whipple from a steg. stage 3. I did absolutely nothing other than swap the injectors & blower. I had a 2.80 pulley 15psi to 3.2 whipple 15psi stayed the same except the #'s

posi said:

Twinscrew? Twinscrew? Did I hear somebody is looking for a twinscrew:dw:?:rollseyes

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Naaah........You know I'm an ole' roots guy Brian. ;-)

Love the roots. Hate the vettes but would love to drive a whipple or KB

liedenfrost said:

We should be able to get more than 500 rwhp/tq with a Whipple with the same stock parts due to the greater efficiency of the blower. How much more...I don't know and was curious to see if anyone knows.

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I see what you're getting at here. The part your getting confused about is PSI, so forget about it for now. Power requires a certain amount of air and fuel no matter how it is being produced. This is a constant, give or take some for air temps and other factors. The fuel and MAF system limit your hp no matter what because the more efficient blower moves more air to make that power. Does that make sense? So yes you could slap a Whipple on at a PSI low enough to keep your MAF from pegging which will still be around 500hp.