What's everybody running for props?
#1
I'm trying to find out what props and on what boats of all you formula owners have tried. Also what were the perfomance differences between them? I am running a 26p Bravo 1 and a 26p Hydromotive Q4 (pitched down). My boat is a 1999 271, 502 MPI, so there might be some differences between the Fastech and earlier hulls. Post any experiences you have had with any props good or bad.
#2
I have a 1989 272 SR1 with twin carbureted 454 Mags and Bravo drives. I initially had 23p Mirage (not +) and the boat performed well, it planed effortlessly topped out at 67 with one motor on the rev limiter.
I then installed IMCO 2" shorter lowers and the 23p Mirages didn't plane very easy. With 25p Mirage Plusses it was even worse out of the hole but both props gave me good top speed at 10% slip. I tried a pair of 26p Hydromotive Quad IV, these were just a little better getting on plane, top speed was around 71 mph. Bravo 1 props were by far the best planing and top speed was close to the same.
I have now installed a pair of Whipple S/C and the only props I am able to plane reasonable with are the Bravo 1, with the Hydros it is extremely difficult to get on plane. I have taken it up to 80 mph with a pair of 28 Bravos with some left and without maximum trim. I now have a pair of 30s coming.
I then installed IMCO 2" shorter lowers and the 23p Mirages didn't plane very easy. With 25p Mirage Plusses it was even worse out of the hole but both props gave me good top speed at 10% slip. I tried a pair of 26p Hydromotive Quad IV, these were just a little better getting on plane, top speed was around 71 mph. Bravo 1 props were by far the best planing and top speed was close to the same.
I have now installed a pair of Whipple S/C and the only props I am able to plane reasonable with are the Bravo 1, with the Hydros it is extremely difficult to get on plane. I have taken it up to 80 mph with a pair of 28 Bravos with some left and without maximum trim. I now have a pair of 30s coming.
#3
I have 1999 271 Fastech with an HP500EFI and 1.50 gear ratio in the Bravo. I am running reworked (thinned, balanced with added cup) 24p Bravo 1. I run right at 5400 rpm and have seen a top speed of 73mph once on GPS (the gods were with, strong tail wind, etc) I can run 69-70 any day in any water, but it is tough to go faster. My hole shot is good, better than with the stock prop.
I am going to try a labbed 26p Bravo and a 26p Hydromotive this summer to see which is better.
I'll post the results when I get them.
I am going to try a labbed 26p Bravo and a 26p Hydromotive this summer to see which is better.
I'll post the results when I get them.
#4
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I have a 2000 271 with a 502, it came with a 26 1.65 ratio. After speaking with a nother formula owner that has a 1999 271 he told me to switch to a 28 p. I took his advise and what I found was I had better speed out of the hole with the 26, but always ran against thr rev limiter. Installed the 28 p and it was a DOG out of the hole but the midrange(cruising speed was better) and picked up a few mph on the top end. Iinstalled stainless marine headers this year with a vortec flame arrestor, and a arizona speed ecu. By doin these up grades I get out of the hole alot faster and the midrange and top end is better. I probly picked up about 4 mph on the top end.
NEVER CHEAT YOURSELF!!!!!!!
#5
formulafastech,
With the stock Bravo 1 26p I ran about 66 mph at 4800-4900 rpm.
I had it labbed and now I run 68-69 on the speedo at 5000 rpm. I have a Hydromotive 26p I am in the process of dialing in, I had it tweaked once but it needs more. I am trying to reach 5200 rpm after having my ECM reprogramed (the rev limiteris now at 5400). The place that did the ECM (Energized Fuel Injection) told me to run my 502 at 5200 rpm for max hp. So far the Bravo has a better mid range, I am running about 54-55 mph at 4000 rpm. What are you guys getting for mid range speed?
With the stock Bravo 1 26p I ran about 66 mph at 4800-4900 rpm.
I had it labbed and now I run 68-69 on the speedo at 5000 rpm. I have a Hydromotive 26p I am in the process of dialing in, I had it tweaked once but it needs more. I am trying to reach 5200 rpm after having my ECM reprogramed (the rev limiteris now at 5400). The place that did the ECM (Energized Fuel Injection) told me to run my 502 at 5200 rpm for max hp. So far the Bravo has a better mid range, I am running about 54-55 mph at 4000 rpm. What are you guys getting for mid range speed?
#6
formulafastech,
All the speeds are from the speedo. I used my buddies GPS once and it showed about 1 1/2 - 2 mph slower than the speedo. With my stock Bravo 26p I never hit the rev limiter, I ran 4900 rpm at the very best. I tried my buddies 24p Bravo and I hit the rev limiter at about 5150 on my tach. I can't believe you have to run a 28p so you don't hit your limiter, something just doesn't sound right. Try a 26p Hydromotive Quad IV if you can get one, it might be what you need.
All the speeds are from the speedo. I used my buddies GPS once and it showed about 1 1/2 - 2 mph slower than the speedo. With my stock Bravo 26p I never hit the rev limiter, I ran 4900 rpm at the very best. I tried my buddies 24p Bravo and I hit the rev limiter at about 5150 on my tach. I can't believe you have to run a 28p so you don't hit your limiter, something just doesn't sound right. Try a 26p Hydromotive Quad IV if you can get one, it might be what you need.
#8
I am running a Bravo 26P, 1.65 gears on my '99 271, 502 Mag. Last weekend I had it out by myself, 1/4 tank fuel, in 55 degree weather and it hit 63 mph GPS at 5000 rpm. This is a new speed record for this boat for me. In Arizona summer temps (105+ degrees) it will top out at 60 and 4900 rpm.
Arizona Speed and Marine is ordering a Whipple setup for me so I will be changing props. For this, I am thinking about a new 5 blade Maximus 28P or 30P. They cost about $1200 though (ouch!!!!!).
Arizona Speed and Marine is ordering a Whipple setup for me so I will be changing props. For this, I am thinking about a new 5 blade Maximus 28P or 30P. They cost about $1200 though (ouch!!!!!).


