Stepped vs Non-Stepped Formula 271
 

Is there a major speed or handling difference between the mid 90's straight hull 271 and the later 90's and up stepped hulls? I'm looking at one with a 502 in it.

TYIA

I have had a 99 271 with 502 stepped for 4 years. I"ve also owned a 272 and a 292. I think the 271 is the best performing boat of the 3. The 271 will hit 68 and cruises nicely at 45. If I slow down a little she will get better then 2 miles a gallon. I highly recommend the 271 with the stepped hull and 502.

Never had a non step but upper sixties is possible

Venting the hull always reduces drag but reduced maneuvering goes with it. The mono hull has a more positive ride but that can be more harsh by comparison to the stepped ride. I was hesitant to get away from the mono hull because of the difference of higher plane speeds too but so far we like the softer ride of steps and the fuel burn is better this way.

Never had a non stepped bird, but I did have a 271 with a 502 and it was a good riding boat. I liked it so much I moved up to a 312 before going to the center console life. You won't be disappointed with a 271.

Stepped hull....ride is way better....wouldn't have it any other way.

Good luck,

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Well guys I know the stepped hull should gain some speed and be more efficient then the straight V bottom. Thought it depend how the hull is stepped
the Formula 271 Fastech is stepped very conservative and have only one step. I have read a lot about the 271 SR and 271 Ftech when it come sto speed
Most Sr1 with 496 Ho or 502 does 58 - 60 mph the 271 Tech the must test results says 63 mph … aprox 3 mph in favor of the Fastech . All GPS speeds
I still have my 1992 271 SR1 with 496 HO and reached my goal of 63 mph GPS actually 63,6 mph … Which I think is one of the best veryfied speedresult I have
been able to find with this set up ;-) My advantage is that the drive is aprox 1 inch higer than original (raised it when fixed the a rotten transom) disadvantage XR Drive
harder to run then a bravo 1 or bravo1x ...
63,6 mph Bravo1 XR Mirage 23+
61 mph Bravo1 XR Bravo1 24
62,2 mph Bravo1 X Bravo1 24 (Had a drive failure on the XR replaced it with new Bravo1 X drive) gained 1,2 mph
I am really looking forward to test the boat with the new Xdrive with the Mirage 23+ next season, maybe it is some speed to gain

Wow, I wonder what’s wrong with Monaco’s boat? 425 hp only gets him to 63.6. That’s pretty good for a 5300 lb. boat. Maybe he should get a gps like yours. I dunno

I have a livorsi gps speedometer. Plenty of people on here with the same results. Jeff wurl

Fantastic I have to say…
In boating magazin they testet the 271 Fastech with that power together with a lot of other boats, top speed 63 mph
The distributer of Formula in Europe got 72 mph 271 Fastech with a Merc 525 ( They know what they are doing by the way)
Your results are amazing I whish I could bee close ;-)

I dear you all who have a 271 SR1 or Fastech who does more then 63 mph (GPS) with 496 HO stock 425 or 502 Stock 415 hp, to post a photo of the speed achived

Jeff I do not doubt your word, its just an amazing result, who labbed your propp ?
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The weight on the 271 dry are 5600 pounds

Here is a snippet of test results from boat magazines for the Formula 271's.
I almost bought a new 271 but the speeds quoted to me by Formula and the
local dealer turned me off. I was told 68ish with a HP525.

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Thank you for this info :-) What it says regarding the 271 is first of all with 502 or 496 Ho its arround the 63 mph (radar, which is kind of accurate) also at this kind of pwer
it is mot very big differanse between the stepped hull and the normal V bottom.
You should have bought the 271, its a great boat ;-) With the 525 the 271 fastech does 72, what is very interesting is the result with the Ligenfelter modified engine 540 HP it does 75,9 mph on the radar, and its an SR1 V bottom, this is a very good result, the boat must have been tuned in perfectly ….
I have this test somewhere and I will post it here ;-) ;-) https://cimg2.ibsrv.net/gimg/www.off...fbe3770cbb.jpg

Out of the water after my 502 545 HP racing engine broke... Installed the 496 HO ;-)
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503 545 HP dynoed
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496 HO

Ligenfelter 271 test
https://books.google.no/books?id=M1H...felter&f=false
Singel engine sport boat test
https://books.google.no/books?id=Z-v...20test&f=false

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GPS said 67

272 very nice classic boats, much bigger then the 271 Sr1 67 mph must be a good result with small blocks ;-) ;-)

To whom are you directing this question?

OK.
I'll get on it.

I took a new pic but there is no 312 with 502's.

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jwurl is running a 28p LABBED prop. Stock prop on a 271 is a 26p stock B1. Major difference A labbed 28 is going to give speeds like a stock 30.So in effect you are gainning 4" over stock or around 6-800 RPM. Still a really good speed for a bone stock 502Mag boat

I have had both an SR1 271 with a 454 Mag and a 271 Fastech with a 502. The sr1 did around 60 @ 5000. The Fastech did low 60's (62-63) @ 5000. All speeds on Garmin GPS.

So except if you compare the result from Jwurl 68 mph, I should be kind of happy with my 63,6 gps mph on the SR1 hull non stepped.
I am looking forward to test the boat next season, changed from an old Bravo1 XR Drive to a Bravo1 X Drive, I have been tod the te XR drive steal more power
then the other x drive :-) Do not now if it will be any better result, lets see. I am also considering to change to Custome Marine headers (CMI Top Split Headers)
The advertising says that they gains power and speed ;-)

Yes the XR drives suck power and speed. My original drive was a 1.65 ratio standard Bravo. Boat was running 68 mph on GPS. I blew the drive and installed a brand new 1.50 Ratio XR. Prop was then switch from a 28p to a 24p Bravo 1 4 blade. Speed was now down to 63 -64 on GPS at best. I have put roughly $50K plus in a complete repower since. 715hp EFI 540 CI, 280 tabs, Imco full hydraulic steering, ect. Now when the boat tops 78 mph it has pretty major chine walk and gets scary. Best I have seen is low 80s wthout having to back out of the throttle. Still have plenty of throttle and RPM left so I think the boat could do mid 80s set up right. Now I am debating having the hull blue printed, possibly messing with extension boxes and drive heights, or just move up to a larger boat with twins. jeff Wurl

Dear Jwurl Very interresting to read your results.. some questions
1 Did you do any testing of propellers before you ending up with the labbed Bravo1 28 pich, what was the results/ improvment
2 What about the ratio 1.65 to1.50 do you think that this will be a big difference when and if you find the correct propeller ? Or is
it only the difference between XR and X drive that has such an impact on the result… My new drive is an Xdrive 1.50
3 How did you mount your 280 tabs ? Mine is parallel mounted take a look at the picture in my earlier post. The owner before me
had a 540 kompressor engine with 840 HP, said that it was a big help regarding the chinewalk ;-)
I am considering to buy a used Procharger to my 496 HO on the lowest boost 3,5 psi it will give my engine aprox 550 hp
that should maybe get me in the low 70 ties :-)

This is what the owner before me posted at this Forum :-)

In "theory" the 1.5 should be faster than the the 1.65. I only ran mine with a 1.65 and got low-mid 70's with ~ 600 HP. The identical boat to mine with a Whipple (~650 HP) and a 1.5 ran high 70's, and touched 80. Can't remember the prop on it.
On mine we tested 26/28/30. Top speed on 26/28 were the same, just 26 @ 6K, and 28 @ 5500. The 30 would only pull 5K, and was slower. But it cruised at super low RPM.
XR straight cut gears eat HP, but also less likely to break if pushing HP through it. Mine was a standard B1 drive and it was run WOT all the time, but it was not beat on getting on plane or jumping.

Yes, 63.6 with a bone stock 502 on an SR 271 is a great speed. And no, adding CMI exhaust to that motor is a total waste of money. You will see nothing except less money in your bank acct. Exhaust only has an effect on power when you modify the stock motor.

Hi Zone 5
I do not have a 502 I have a 496 HO
its a 2009 model so its time to change the manifolds anyway..I have an offer to buy this CMI Headers for 400 USD :-) I will of course pressure test them first
Maybe it will give me some more power I do not know

My 280 tabs are mounted at the same angle as the hull and mounted 3/4 inch up from the edge . That is the way the mercury instructions said to mount them. The drive is a 1.50 ratio because that is the highest ratio you can get in an Xr.

Jwurl, I think is the most common way to mount the 280 Tabs
If you look at the picture of my transom you can see how the 280 are mounted.
According to the owner before me, this way works very well to avoid chine walking on the 271.. I can not confirm it my self, because I am so far at 63,6 mph he he
I have seen that some Fountains are done the same way as mine