I have 4 blade, I played a little with cupping. To make a long story on my 26x26 they were just fine at 26x26 with no cup for my naturals.
The turbos were take outs from a boat we were putting new larger engines in. The problem I have is the transmissions that came with the turbos were the wrong rear ratio. However the gears were very heavy duty (forget the model #) and over sized for the horse power of the turbos, so I choose to keep them. They are almost as big as the engines, HA, HA I do not remember what size injectors I had. If under no load you are getting the rpm the book calls for and under load you are getting the correct rpm's than your props are the correct size Fuel consumption is RPM, if you want to go 8 or 10 knots you will MAKE fuel after that you will need to buy a gas station. Have a nice day, Perry _____ From: [email protected] [mailto:[email protected]] On Behalf Of Ross Robertson Sent: Monday, October 11, 2010 1:18 AM To: [email protected] Subject: RE: [UnifliteWorld] 38C - 6/71NA Performance data. Are the turbos on new engines or have you turbo'd the 671 naturals...? I have 24 x 26 props at present.. so 2" less pitch than you had. Can you remember : Were your props 3 or 4 blade, cupped or uncupped ?? According to the DD Field Service Data book, with turbos and N 90 injectors, my 671s have 325 SHP..As of now I don't see it but I'll get there. Kind Regards, Ross _____ From: [email protected] To: [email protected] Subject: RE: [UnifliteWorld] 38C - 6/71NA Performance data. Date: Sun, 10 Oct 2010 19:55:38 -0400 You can not go by me, I am over propped now. I know when I had my naturals back in 1999 got around the 32 gph at 26x26 props. I am saving up to get new props for the turbos I have. Capt Perry _____ From: [email protected] [mailto:[email protected]] On Behalf Of Ross Robertson Sent: Sunday, October 10, 2010 10:22 AM To: [email protected] Subject: RE: [UnifliteWorld] 38C - 6/71NA Performance data. Hi Captain Perry, good to hear from you I don't have accurate figures. I use about 100lt hr which = about 26.4 galls hr - but this is usually at 1500 rpm. I am now going for original performance ( if possible ??)as I now have the power. What size / type of props are you using...? Are you able to cruise at the figures I gave with the same WOT --.e. 19 / 22 knots ?? Look forward to hear from you, Cheers Ross _____ From: [email protected] To: [email protected] Subject: RE: [UnifliteWorld] 38C - 6/71NA Performance data. Date: Mon, 4 Oct 2010 15:13:55 -0400 What is your fuel consumption at 1900 RPM?. If it is around 32 GPH I believe that is correct. _____ From: [email protected] [mailto:[email protected]] On Behalf Of Ross Robertson Sent: Monday, October 04, 2010 11:42 AM To: [email protected] Subject: [UnifliteWorld] 38C - 6/71NA Performance data. Hi, In the 38C performance spec I have down loaded, it states Cruise --19 knots. Max Speed 22 knots. This I assume is with the almost standard J & T 6/71NAs in the 38Cs I cannot get near these figures. It is quietly driving me nuts. The only thing I do well is gulp diesel fuel and never get far from base....but refueling is easy near a major port -- Jakarta Back to the Spec -- for Cruise 19 knots I anticipate this is @ 1800rpm. WOT 22 kn I guess also is @ 2300 rpm. I would appreciate anyone, who has good data in this area, to be kind enough to pass on to me their rpm / speed figures. Also their prop details - Number (3 or 4 ) and type of blades ( cup or plain ) pitch and diameter. Now to the question of power. Here in Indonesia we have diesel 2, not diesel 1 as in the US of A ( I think). To take care of the power deficiency I blew the engines fitting turbo's and inter-coolers. They are working fine but I see no performance improvement. I run with just the smallest, 'happy' wisp of white smoke.. The new engine config' According to the DD manual has at least the power of the original J & T Nas So next guesstimate is I have a prop problem... Thus if a splendid 38C owner is still able to run at the spec figures in para 1 above, I would dearly like to know his or her prop dimensions and speeds at different rpm -- clean ( or dirty) bottom -- from the boonies -- Cheers Ross -- You received this message because you are subscribed to the Google Groups "UnifliteWorld" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/unifliteworld?hl=en. -- You received this message because you are subscribed to the Google Groups "UnifliteWorld" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/unifliteworld?hl=en. -- You received this message because you are subscribed to the Google Groups "UnifliteWorld" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/unifliteworld?hl=en. -- You received this message because you are subscribed to the Google Groups "UnifliteWorld" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/unifliteworld?hl=en. -- You received this message because you are subscribed to the Google Groups "UnifliteWorld" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/unifliteworld?hl=en. -- You received this message because you are subscribed to the Google Groups "UnifliteWorld" group. To post to this group, send email to [email protected]. 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