I have seen that some Coronet 21 DC originaly was delivered with Twin Volvo Penta AQ130 engines. Do anyone have some experience with this setup conserning: weight, handeling, topspeed, fuelconsumption, maintainance? To me it seems like an extra cost to have two engines.

Hi Nils,

I have only had twin engine Coronets, my first was a -69 Weekender 24 with twin 120/200. It made 34 knots top and 22 cruising at around 1.5 l/nm.
Then I had a DC21 from -73 with twin 130/250 which made 37 knots top and 26 cruising at appr 1.2 l/nm. Both were a year old when I bought them and worked without any hickups, the DC21 I kept for 8 years and sold only because I bought the 24 Patrol.
I think the weight was no problem, the handling couldn´t be better and I am still in favour of twin engines even in small boats. Like the upcoming VP D3 with 200+ hp.
My old DC21 can be seen in the picture archive as the one with wooden rails. A special option, like the front windows on hinges. This boat had it all, but was later converted to a single B30 of all engines!?
I once tried one DC21 with twin B30, but it was very heavy in the back and did not perform well, top speed was only 36 knots but might have been a couple more with the right props. My P24 made 36 with these machines at almost 4 tonnes of displacement!

I have had a 21DC with 2 x AQ131A (B23) for 4 years now and has finally taken the decision to replace them with a VP570/290DP. In terms of handling the boat has been perfect both in harbour and out on the open sea and there is always an extra engine to take you home if one brakes down. The fuel consumtion has been approximately 1,5 - 2,0 l/nm. Topspeed has been 39 knots (gps) and cruising around 28-30 knots. The negativ side is the noise and the cost of repiarness though if something brakes on one machine it will brake very soon the other. With a V8 and 290DP I will get 45 knots topspeed and 32-35 cruising at 1,2 - 1,5 l/nm and with a third of the noise before. It has taken me 2 years of considering before taken the decision and I am very eager to try the new engine out in 2 weeks time from now. I am certain that if Nimbus 21DC was motorised with a 5,7l V8 and 290DP it is the right engine for this hull and size of boat.

Hi Anders,
I think you are right on the speed and fuel consumption on the V8, but the noise...
I have had VP V8:s before, but now having experienced the newer 270/320/DPX in fast boats I have found them extremely noisy. Mainly the exhaust sound that is not even nice, just noice. From where I live, close to the sea, I hav also noticed that the newer makes more noise when passing. New VP drives will most likely come and hopefully they can take better care of the exhausts than the present ones.
By the way, the advantage of the twin B20 I had was that they could be driven below the "noise barrier" and I remember them as very quiet...!

Correction; I was thinking of the DP-S, not DPX. All theese mysterious letters...

Thanks allot for the answers! Have just bourght a 21 DC with twin AQ 130 engines. I am looking forward to get in the water, but there is still some work to be done. The boat is very original but needs complete rebuild. The deck is in original gelcoat and already rebuild. The hull is painted, but it seems like I will succeed in removing it, and the gelcoat underneath is in relatively good condition!

Concerning the B20 VP motors & petrol vs diesel motor. The B20 petrol motors are VERY quiet compared to any diesel & much less vibration. But - diesels are better economy & safer fuel, though fuel cost approx equal. I'm Refitting a 22ft explorer & not sure to fit a B20 AQ130/140 or go for a diesel, but haven't seen any that compare to the smoothness of the old B20? would look for a diesel, with a bosch pump that would run on Biodiesel. any help, thanks....

I've got a 21 daycruiser with a V6-205/280 combo. The boat was one of the single 170 B30 versions when new. One thing worth thinking about is a 225Hp Vortec V6 engine as it'll fit in your original engine compartment. I've just built a 6.2 Vortec V8 for mine. It's based on Mercruiser Black Scorpion 340hp components but I'll be running some free flowing exhaust and a silent choice system and hope to be somewhere near 370hp. I know 370 is a bit much but I've seen a Big Block Chevy in a 21. Should be fun...now where are my pills :)

Hi there
What is the best size of motor for 21 DC. My boat is from 1971. Now I have a Volvo Penta 220 HP (hestekræfter) V6 og duoprop in stainless steel. How big an motor can i use ? How big should a motor be if I have to motors in my boat ?

Hey!
I have a 21 DC with twin AQ 130C / 270, and would like to know the size/pich of propellers they had from new..
I have 15x17 on my boat, and i am not getting above 25-27 knots at 4500-4700 rpm.
I know i can get some knots by polishing the bottom of the boat, but surely not 10 knots?
I have been receiving different advice from different people, so i am a little confused now..
Some people think 15" is too big for a twin installation.
The engines run really strong, and i reach top rpm quite easily..
Any advice would be very apreciated..