So what's the internal engine differences between the 1250 Super BP with stacks and the 1350 Stacker? I see in a previous post the supposed HP was significantly higher.
thanks
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So what's the internal engine differences between the 1250 Super BP with stacks and the 1350 Stacker? I see in a previous post the supposed HP was significantly higher.
thanks
Dale, looks Beautiful, WOW...just WOW !!
Spectacular ! :thumbsup::thumbsup::thumbsup:Quote:
Originally Posted by 25ss
It appears that rather than clear this up, I've made it more confusing. :o I'm guessing you are looking at the numbers that I gave to Dick - 1250 SBP Stacker @ 155 and the 1350 Stacker built at #38 @170/175. This is really two different powerheads. The first is the 1250 SBP, assembled with standard parts for the APBA build requirement of one hundred units with a stacker kit installed later. The second is a from scratch, blueprinted 1350 built by the race team. The 1250 SBP was supposed to be 140 HP and about 155/160 with stacks. The 1350's from the race team were sent over to Plt#6 for break-in and dyno check and I "thought" the reported HP was around 175. That's why it appears on my list to him as it does, but you will note that Dick said that he didn't have intimate knowledge of what we built at #38, so those powerheads were not included in his quoted HP figures.Quote:
Originally Posted by Tom Smyth
I'm going to try to get the load chart posted, then maybe we can all have a reasonable discussion about what the HP of this group of motors really was. I have a few more emails from Dick that are related to this subject and I'll try to get those up as they apply to what is being discussed. He also sent an excellent explanation of the difference between the 1250 crossflow and the 1350 direct charge, you guys will want to keep it in a frame! :thumbsup:
Ditto - that's one beautiful boat!Quote:
Originally Posted by Bob V
Looks like you took a time machine back to 69-70, took a couple pics and posted them here. Great job !!!!!!!!!!
---Hope this works----
http://i42.tinypic.com/2qncdxt.jpg
[QUOTE=willabee;2577640]
LOAD CHART back
Hi Bill,
I will attempt to keep this short & pithy.
These horsepower numbers (I’m not trying to be rude) that used to fly around the racing community were generally based on a misunderstanding of the entire concept of what it took to make a boat go faster. Basically, the boat load curve for a typical boat was a 2.5 exponent as best I can recall. Keep in mind that circuit racing is all about matching the propeller to the engine characteristics keeping in mind the boat load curve and, of course, the available power out of the turns.
in place
Your bhp numbers remind me of stories about fishermen who go out and catch a 15” bass, and by the end of the night at the bar the damn thing grew 10 inches! Now, I don’t have intimate knowledge of what you guys built at #38 and the only numbers I will quote are corrected (SAE Standard) bhp numbers.
Let’s start with the stackers. Keep in mind that they relied primarily on acoustics (based on organ pipe theory) for any bhp increase of the stock configuration. I am assuming that you are referring to the six single-stack 8 degree megaphones which had a very narrow rpm range in which they were “on the pipe.” By the time they got to 6000 rpm the power was falling off very badly (see chart below). None of those engines with the Kiekhaefer internal reed block ever saw 160+ bhp on gasoline. It was a physical impossibility because of the reed block restriction and the pipe characteristics. As I told you before, I did develop a 16 degree setup (3 stacks instead of 6) that maybe broke 170 bhp, but they were never raced nor did the public ever see one (there was only one). It had a broader power curve but was never tested on a boat.
The original Twister 1 produced essentially the same peak power as did the stacker, but there was very little pipe tuning - - only pulse tuning, and that was true of everything from there on forward. All were pulse tuned. When we went to the Tillotson setup on the TII it was a major disappointment for me. We picked up maybe 10 – 12 bhp but we still had the rpm range limitations which really screwed up the prop/load issue. We did not realize at the time that the piston rings were going into resonance somewhere above 6000 rpm and that phenomena played a major role in extending the power curve to higher rpm’s.
Now you mention a TII+ built at #38 and I don’t know what that configuration was. All I can tell you is that it could not have had the same power curve as the TII+ configuration that Mert drove at Kaukauna. That engine had all kinds of tricks in it; pistons, rings, ports, etc. and it was an excellent match for the early V-6 racing engines but the durability was very short. The C6 was not competitive with the TII+ that Mert drove. That engine was a real screamer and the power range ran out to ~7800 rpm.
Now, I will show you a chart that includes four engines plus a boat load curve. Remember this is 40+ years old but has not been “recalibrated” with the special effects of Miller High Life.
http://mail.peggyspride.com/edgedesk...450&download=2http://i42.tinypic.com/2qncdxt.jpg
The abscissa (X-axis) is rpm and the ordinate (Y-axis) is corrected SAE bhp. Now, if you think about running a closed circuit course and the objective of minimizing lap times you can see why the stackers were lackers because of their very peaky power curve. Matching a propeller to the power curve was extremely compromising. The other extreme would be the two-of-a-kind TII+ engines that you could run laps in the 5000 to 7500 rpm range and they would completely destroy the T-2.
In closing I know how racers like big horsepower numbers but the reality of the situation is that peak horsepower is almost meaningless. For example, we built a turbo charged I-6 and V-6 and we got 350 – 360 bhp from the V-6 but an ordinary T-2 would blow the doors off the damn thing in a circuit race. This was another one of ............ big ideas and he didn’t understand the importance of torque/power relationships either. That operation along with ........... .......... -shaft gear case that had so much steering torque that no one could drive the damn boat for more than 10 minutes was ................................................ Oh well, that’s another story.
Anyway, that’s it. As I pointed out peak horsepower talk is virtually pointless when it comes to matching a fixed propeller to an exponential boat load curve. That is an important lesson that I realized early into the development of the Twister. The problem we had was extending the power curve out into and beyond the 7500 rpm range and when that finally happened it was a whole new ball game!
Take care,
Dick
From: bw@
Sent: Friday, June 14, 2013 1:09 PM
To: Dick Lanpheer
Subject: Re: stacked 1100's .....
Thanks for all the info, I didn't get bored (might have dosed off a couple of times http://mail.peggyspride.com/edgedesk...mages/e_03.gif ). Please do me a favor and tell Ted that I said Hello and wish him a Happy 80th! If you're up to it, you might ask about the 200 hp. I'm talking with a bunch of history buffs on the internet and I would like to clear up the issue of the real horsepower numbers on the BP's, stackers and Twisters, including the C6. Some of us think the HP was as follows:
1000 BP - 100
1250 BP - 125
1250 SBP (1350 direct charge) - 140
1250 Stacker SBP - 155
1350 Stacker built at #33 - 170/175
1350 Twister - 170/175
1350 Twister I (new reed blocks, exhaust mod) - 175/180
1400 C6 - 190/200
1400 TII (Tillotsons) - 190/200
1500 TIIX - 190/200
Enjoy the party, Bill
<!VMDG>
I would love to know what you think was different between a 1350 Stacker and a 1250 SBP.
Conrad
First a big ....."Thank You Redbird" ..... we now have the load chart where it should be in Dick's email about these motors. It's all together for easy reading and comparing. :thumbsup:Quote:
Originally Posted by milkdud
Now, to your statement ..... Again, I am probably guilty of using a bad phase when I said " this is two different powerheads". As I have stated many times, the 1250 Super BP is really the first 1350. When I was there I never called them an SBP, I always referred to them as 1350's. The first four of these ran at Havasu in 1968. Tom Stickle ran one of them and was leading the entire field at the two hour mark ..... a single engine 18' rocker bottom Molinari in front of 120 different entries, most of them with multi engines, amazing! He blew over and I had to take it to the local dump so that it could be dried out and readied for Sunday without allowing anyone to see what was under the cowling.
What I was trying to say is that the 1250 SBP was a "production" built engine, just assembled, nothing special done to it. When the stacker kits were made available to the racing public, you just bolted them on. I was trying to compare them to the "hand built" units put together at Plt#38 Racing for the Team boats. I was trying to make that distinction for Mr. Lanpheer so that we received his feedback on the HP of both versions. However, when he replied, he said that he wasn't intimate with what we were building at that time so his quoted numbers would only include the "production" version with pipes.
His chart shows that version peaked at 152ish. I think I remember Doug Hamilton, the foreman of the shop at Plt#6, telling me that the powerheads we sent for dyno check were around the 170 hp range. Can't prove it, it's just what I thought I was told at the time.
BTW, in an attempt at humor, I could have just said the 1350 stacker had pipes and the 1250 SBP didn't .... :D
I see the hp figures. What makes the hp, is the question.? Looks like the 1350 stacker used the BP mid with as SSM.
I assume the 1350 stacker was used in 1970-71 by factory drivers. Did non factory drivers have to use up old Super BP's in 1970-71 to race? The Twister did not come out until late 1971 it think.
I would imagine the 1350 Stacker had less hp than a t2 for sure and possibly less than a 1971/2 Twister.
Thanks Conrad
Thanks guys i really appreciate the come backs.
I have had the boat a while and it has taken time to get it together for the vintage look with the stacks.
On the engine i said 1350 it is a 1250 SBP
I think of it as a 1350 which it pretty much is
As you can see from Genes dyno sheet it has a very narrow power band.
It wants to lug or scream making it hard to prop if i had water injection it might be better.
The sound is very cool but gets old fast.
Its more fun to drive with a quiet 1500 but doesn't have the look of the stacks
.Thanks Dale
The non water injected stackers had a very hard time accelerating on single engine tunnel boats, especialy downwind.... You might consider modifying the elbows and adding water injection.Quote:
Originally Posted by 25ss
You made that mid section right Dale? Is it 12 inches? I got to see Dales' boat in Tomahawk 2012. I stared at it for a good hour.
Conrad
Looks like the inline 6 history is something like this:Quote:
Originally Posted by milkdud
1965 - 1000 - 100 hp - a few 6 pipe stackers, maybe 110 hp
1966 - 1100 - 110 hp - a few 3 pipe stackers, maybe 125 hp
1967 - 1100 - 110 hp - a few 3 pipe stackers, maybe 125 hp - the first 1250's run at Salton Sea
1968 - 1250 - 125 hp - several 3 pipe stackers, maybe 140 hp (crossflows) - the first 1350 direct charge motors run at Havasu
1968 - 1000 BP - 100 hp - 89.9" crossflow
1968 - 1250 BP - 125 hp - 99.9" crossflow - several 3 pipe stackers, maybe 140 hp
1969 - 1000 SBP - 115 hp - 89.9" direct charge
1969 - 1250 SBP - 140 hp - 99.9" direct charge - lots of 3 pipe water injected stackers with BP DSH & SSM, maybe 155 hp (counter rotating for twins)
1970 - 1350 Twister - 155 hp - 99.9" direct charge - available to racing public in 1971 with MCI SSM - first C6 runs in Berlin
1971 - 1350 Twister I - 160 hp - 99.9" direct charge - 3 transfer ports & scalloped reed blocks - available to racing public in 1972 as whole engine or an update kit
1971 - 1400 C6 Morgan carbs - 170 hp(?) - 99.9" direct charge - team boats run a few in Miami in July
1972 - 1400 C6 Morgan carbs - 170 + hp(?) - 99.9" direct charge - all team boats run this motor (4 of Lanpheer's version run at Havasu)
1973 - Twister II Tillotson carbs - 170 hp - 99.9" direct charge - first T3 runs at Paris
1974 - Twister IIX - Tillotson carbs - 175 hp - 99.9" direct charge - porting changes
I think the horsepower listed above is within 5 hp of what Dick said they saw on their dyno. They didn't dyno a C6, that's why I put a question mark there. The other factor not considered in this is the "hand built" powerheads that came from racing. They were better than the "production" powerheads built for the racing public. Consequently, I still think they had more HP than what is listed above - just my opinion.