Like the title says are there any 660 or 685 turbos out there? How are they running? I would like to try a 685 kit on my T600 I know I have seen a few advertised but never heard if they ever made them run.. Any info would be nice
any 660-685 turbos out there?
- Thread starter happylilcuss
- Start date
Im running a 685 on mine and have a NIP Higmark rec turbo kit. Just never got to install it and decided to turbo my 900 instead. My lil 685 hauls the mail 
As you may or may not know I spend a lot of time down at Carl's and this is prospect is often in my thoughts and the conversation has been had many times. My vision is a CFI 660 with a pump gas garret style. Essentially you have a 700 turbo and when we spent some time testing the offerings from Boondockers the 6 and the 7 were so far off from the 8 that it just didn't seem that exciting a prospect.
Now the difference here is the carb'd version and the fact that most of the big bore small blocks are on some kind of porting and slightly elevated compression over a stock 600. Turbos are sensitive to porting (not that you can't port one and have success because I have a radical 670 rotax that is turbo nitrous and ported and it hauls the mail) and nobody has really been willing to spend the money as a pioneer to find out on this application. I think they have the theory down and by speculation simply reworking the head to mimic our early turbo days would result in a nice setup. The other real question is will the performance standard be as radical between big bore and turbo as it is between stock and turbo and I think most likely not. Then it's not worth the big bore plus the turbo. Also think there is such ease and high performance in the 800 stock with turbo that most shops aren't going to invest the time and money on something that doesn't appear to be marketable.
If you want to give her a run I have a nice turbo setup ready for your credit card. Gonna bet Wurston could custom make you a head. Do it..I want to know!
Now the difference here is the carb'd version and the fact that most of the big bore small blocks are on some kind of porting and slightly elevated compression over a stock 600. Turbos are sensitive to porting (not that you can't port one and have success because I have a radical 670 rotax that is turbo nitrous and ported and it hauls the mail) and nobody has really been willing to spend the money as a pioneer to find out on this application. I think they have the theory down and by speculation simply reworking the head to mimic our early turbo days would result in a nice setup. The other real question is will the performance standard be as radical between big bore and turbo as it is between stock and turbo and I think most likely not. Then it's not worth the big bore plus the turbo. Also think there is such ease and high performance in the 800 stock with turbo that most shops aren't going to invest the time and money on something that doesn't appear to be marketable.
If you want to give her a run I have a nice turbo setup ready for your credit card. Gonna bet Wurston could custom make you a head. Do it..I want to know!
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Spaarky
Well-known member
I think that the 685 is a great idea... but I am going to give you a little different perspective on it. F-bomb is right, turbos dont like the porting that typically would be on a BB small block. You may be looking at new cylinders or if it is possible getting your cylinders ported for the turbo. Porting for a turbo is sketchy IMO. Some have done it/are doing it, but I dont know if there is really that much to gain. In the end, a stock porting is the most reliable. I just hate to see people being guinee pigs(sp?). Unless you have very deep pockets to support that.
One kit builder told me he spent $30,000 in motor parts to get a sled running perfectly. Think about that for a minute.
I find it hard to believe that there was that big of a difference between the 3. That has not been my experience. Some of the kit builders will even tell you their 7's will out run their 8's. Yeah, doesnt make sense, but I have seen it before.
If it was me here is what I would do. Obviously you are not afraid of a carb turbo. Contrary to most belief, they are very simple and easy to tune. Sell the little small block BB, and buy a old carb 700 or 800, your choice. Lets say you can sell your small block for what 1500+. You can pick up a 700 for under a $1000. Then drop that in your chasis(very simple task), and do a turbo version of that. The only disadvantage would be the added weight, but you are adding a turbo and a bunch of other parts that will add up too.
This means you would have the same or more HP than the small block. You would then be back to stock cylinders... easy to find and cheap. The 7-800 set up is already proven and your not reinventing the wheel.
this is just my opinion... if you want to turbo the small block... go for it, but be ready for what could be some frustration and lost riding time along the way.
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Yeah I hear all of the responses. I love the power that I have with my T600 that I am running now. It has been absolutley bullet proof. Pull and go sled for 3 years.. With that said I have been finding myself cranking the boost way up and wanting more.. I have thought about just buying a 700 and bolting that in but I have also been very curious about the 660-685 idea too. I think a carb t700 would haul the mail. Anyway its just fun to pick everyones brains and see what has been done or discussed as in robs case..
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Spaarky
Well-known member
They do... I love mine. I bought a 600cfi, yanked the motor, and dropped in a carb 700. The money I made on the motor swap almost paid for my turbo set up. I am lucky enough to have a turbo genius for a best buddy. Twister built my set up and it smokes. Bottom end of a WC motor and the top end is like the enegizer bunny... just keeps going and going.
I love the 700 motor.... you can crank the boost until the turbo will explode, but the motor will still live.
If you ever need any help just shoot me a PM.
The 685 is very doable and would run fantastic. You better be a person with a lot of patience though. You could nail it right away, or you could fight through it for a season or longer.
