Building a new Seven

[Tbox56]

My tame is Tom and I am new to this form, I owned a Europa twin cam in the mid 70’s and always admired the Sevens. Tomorrow I am headed to Texas to meet with Dick Brink and likely order a Birkin. My biggest dilemma at this point is what engine to go with 2.0 Zetec, 2.0 Duratec, 2.3 Duratec or Busa power. I know Birkin doesn’t offer a prep for the Busa engine and gearbox and I would have to do some modifications to make it work but that doesn’t scare me. I am concerned about the longevity of the Busa setup since it’s original design is for a motorcycle of what 600 lbs with rider and using it in a 1200 lb car. I lean toward the Duratec because it is a newer engine than the Zetec. I would like to see something in the 250 hp range if I use a car engine. I like the higher RPM of the Busa and know I wouldn’t get or need the same hp with the Busa. I think my use will be split 70/30 between street and track. Any thoughts or suggestions.

Thanks

[11Budlite]

Welcome Tom,

 

I have a Zetec in my Birkin and am very happy with it, but if I was starting over I would definitely go with a Duratec. Lighter, more modern design, and better cylinder head/bigger valves so much easier to get 250 hp out of a Duratec. Not sure between 2.0 and 2.3, but I thought the 2.3 had a longer stroke and was taller so could have more fitment issues. Also the exhaust is on the passenger side for LHD cars so I would consider that a benefit as well. Dick Brink is a good guy to go to for all things se7en.

 

I'm more of a car engine guy, but I'm sure some of the BEC guys will be along with their recommendations. Good luck in your search.

 

Bruce

[JohnCh]

If I was planning to use the car mainly on track, then I would be very tempted by a BEC. The light weight, sky high revs, lack of reciprocating mass, and the sequential gearbox are at home in that environment. If, however, I was planning to use the car quite a bit on the street, then I’d go for the Duratec. Which is exactly what I did.

 

The 2.0L and 2.3L share the same head and bore dimensions, but differ in stroke length and block height (the 2.3L is about 14mm taller.) 250hp is easily, although not cheaply, achievable in either configuration. As you would expect, the smaller engine makes power with revs, whereas the stroked version relies on big gobs of torque. I currently have a 210hp 2.0L Duratec and love it. I wish it was a bit more frantic up top, but the broad torque curve is pretty compelling. With my gearing, 7500rpm in 3rd is 102mph – so not particularly short – yet starting in 3rd from a dead stop isn’t a problem and still results in strong acceleration.

 

-John

[Hank]

I bought my MEGABUSA for the ultimate track day experience with the budget I have. Although my car is not finished yet my FlatShifter paddle shift setup arrived today in the mail. Paddle shifting the sequential motorcycle tranny around the circuit without the clutch will be a big plus. I believe the sequential trannies offered for the Car Engined Cars (CEC) are expensive adders indeed (i.e. Quaife). Power to weight was my deciding factor and the Bike Engined Cars (BEC) have that stock. Now if you modify a Duratec engine then the BEC's power/weight doesn't shine as much. Longevity is an issue with modified BECs or so I hear. Turbocharged BECs are the worst. Maybe I will prove them wrong if I get bored with the stock Hayabusa power this fall.

 

I'm ditching the factory reverse box for either an electric or manual reverse. More on that in the coming weeks.

 

Take what I say with a grain of salt. My car has yet to hit the road (other than on the back of a 20' trailer). She's been up to 70mph though!

[scannon]

Let me offer a slightly out of the box alternative. I have an internally stock 1,800 cc Miata engine with a turbocharger in my Caterham. It dyno'd at 301 RWHP and 260 lb ft of torque. It is totally docile in normal driving, not fussy or high strung at all, that is until you allow it to go into boost.

 

Since the Miata engine was originally designed as a turbo engine for the 323 GTX/GTR it is capable of handling those levels of power without internal mods as long as you keep the rev limiter at 7,500 RPM. With internal mods you can easily get 350 - 400 hp. One person has taken a 2.0 version to well over 600 hp for a dragstrip Miata.

 

Skip

[Tbox56]

Skip,I met you at Jeff's house, I think it was 2 summers ago, and went for a ride in your car. You were still getting it dialed in at that time, sounds like you are all set up now.

 

Thanks to everyone for the feedback so far.

 

Tom

[scannon]

Skip,I met you at Jeff's house, I think it was 2 summers ago, and went for a ride in your car. You were still getting it dialed in at that time, sounds like you are all set up now.

 

Thanks to everyone for the feedback so far.

 

Tom

Tom,

 

I sorta remember meeting you there. The car only had 234 hp and 201 torque at that time. It's lots more fun now.

 

Tom should be coming down from Alaska soon to work on his Se7en at Jeff's shop. We usually have a Sunday midday gathering to drink a few beers and tell tall tales when he is here, you should join us again.

 

Skip

[DB6]

My tame is Tom and I am new to this form, I owned a Europa twin cam in the mid 70’s and always admired the Sevens. Tomorrow I am headed to Texas to meet with Dick Brink and likely order a Birkin. My biggest dilemma at this point is what engine to go with 2.0 Zetec, 2.0 Duratec, 2.3 Duratec or Busa power. I know Birkin doesn’t offer a prep for the Busa engine and gearbox and I would have to do some modifications to make it work but that doesn’t scare me. I am concerned about the longevity of the Busa setup since it’s original design is for a motorcycle of what 600 lbs with rider and using it in a 1200 lb car. I lean toward the Duratec because it is a newer engine than the Zetec. I would like to see something in the 250 hp range if I use a car engine. I like the higher RPM of the Busa and know I wouldn’t get or need the same hp with the Busa. I think my use will be split 70/30 between street and track. Any thoughts or suggestions.

Thanks

 

 

err, 250 for mainly street use??? think on my friend.

[Tbox56]

You think over kill, my problem is any tracks are over 120 milea away and I would be driving there. I want a killer street car and a good track car.

[jturrell]

I'm not sure about bike engine longevity in a seven, however there is a lot of data on this for Radicals. I would assume that the longevity numbers are similar as the cars weigh about the same. The Radical factory recommends a "refresh" about every 30 hours of race time. For track-days, it's about every 40-50 hours. For regular street driving . . . I don't know. Not many of these cars on the roads.

 

My refresh ran around $3500 for a wet sump 1300cc Powertec Hayabusa. You could buy a brand-new 2.0 duratec for less than that (without the ancilliaries of course).

 

If I decide to take the plunge on a seven (I'd really like to.), it'll be a 2.0 Duratec, and hopefully an Elite 6 speed sequential. It's cheaper and lighter than the Quaife. The sequential transmission in my old Radical was so much fun . . . I'd really like to have it in a seven.

 

Duratecs are so cheap, I don't think I'd go with the motorcycle engine option. It was fun in my Radical, but it will cost you a lot more in the long run. You may have additional hurdles with emissions testing, etc. In my mind, the bike engine isn't worth the hassle.

[DB6]

Let me offer a slightly out of the box alternative. I have an internally stock 1,800 cc Miata engine with a turbocharger in my Caterham. It dyno'd at 301 RWHP and 260 lb ft of torque. It is totally docile in normal driving, not fussy or high strung at all, that is until you allow it to go into boost.

 

Since the Miata engine was originally designed as a turbo engine for the 323 GTX/GTR it is capable of handling those levels of power without internal mods as long as you keep the rev limiter at 7,500 RPM. With internal mods you can easily get 350 - 400 hp. One person has taken a 2.0 version to well over 600 hp for a dragstrip Miata.

 

Skip

 

Hi Skip,

I had no idea that you had that Mazda set up, I had no idea that would fit; was it straight forward?Looks very good and reliable too no doubt

[scannon]

Hi Skip,

I had no idea that you had that Mazda set up, I had no idea that would fit; was it straight forward?Looks very good and reliable too no doubt

 

DB6,

 

It was a fairly easy installation. We fabricated motor mounts similar to the Caterham units and machined the transmission to use the Caterham rear mount. Wiring in the Link ECU took about 80 tedious hours. I have since re-wired to use the Hydra Nemesis ECU and water/methanol injection.

 

There are more pictures and a "how it was done" writeup at http://www.britishv8.org/Other/SkipCannon.htm.

 

The build log is at http://www.cardomain.com.Skip/ride/2175152

 

Skip

[yellowss7]

 

Duratecs are so cheap, I don't think I'd go with the motorcycle engine option.

 

I'm curious... Could you explain Cheap? I've seen the prices on the Cosworth site for a 2.0. at 10K plus.

 

Where do you get them for $3500? What level of Hp? What other ancillaries are needed and at what cost?

 

ECU,Mapping, TB's etc.

 

Tom

[DB6]

Tom

I was thinking that myself.

I know the prices are lowest on the Xflow,then the Zetec with the Duratec thru the roof.

[Hank]

The Radical factory recommends a "refresh" about every 30 hours of race time. For track-days, it's about every 40-50 hours. My refresh ran around $3500 for a wet sump 1300cc Powertec Hayabusa.

 

What is included with a refresh? What is required?

 

I figured I'd change the oil every track day and put gas in it.

 

I paid $3000 for my 2005 Hayabusa motor complete with wiring harness and ECU with 4000 miles on the clock.

[Ian7]

 

... and hopefully an Elite 6 speed sequential. It's cheaper and lighter than the Quaife...

 

 

Before taking the plunge, check with Taylor Race Engineering in Plano, TX. They do both Elite and Quaife, may advise you to go Quaife in a street car. (Thats what I chose). Elite's had some durability issues in Formula Enterprise chassis'.

[Sean]

I'm curious... Could you explain Cheap? I've seen the prices on the Cosworth site for a 2.0. at 10K plus.

 

Where do you get them for $3500? What level of Hp? What other ancillaries are needed and at what cost?

 

ECU,Mapping, TB's etc.

 

Tom

 

I did a quick search and immediately found a complete 2.0 for under a grand:

http://cgi.ebay.com/ebaymotors/08-Ford-Focus-2.0L-DOHC-Engine-2.0-Duratec-Motor-4K_W0QQitemZ350152855881QQcmdZViewItem

[DB6]

I did a quick search and immediately found a complete 2.0 for under a grand:

http://cgi.ebay.com/ebaymotors/08-Ford-Focus-2.0L-DOHC-Engine-2.0-Duratec-Motor-4K_W0QQitemZ350152855881QQcmdZViewItem

 

Sean, I agree with that, however, if you look back the earlier posts were to do with 250 hp plus with reference to Caterhams via Cat USA/Cosworth.

I am sure that a basic 130 hp low mile Duratec off a modern Ford could be found at a local wreck yard for @1K.

I also think that the Caterham USA engine costs are way high across the board, (I guess there are other companies tuning this engine,I wonder what they charge)

To be frank, if I was doing this over again myself I think I would def go Japanese on engine and trans.

Note: it is common knowledge that Mazda used the original Lotus Elan as a model for the Miata right down to the sound of the exhaust, but the engine even looks like ringer for the Lotus twin cam too,and I have not heard a bad thing about that engine(or come to that any other Japanese engine).

In an even Tbox56, Dick Brink is as capable of answering your questions as well as anybody, and a knowledgeable7 enthusiast .

PS, you say you would not mind taking on the bike engine even tho you would be swimming alone, I applaude you sir,but I myself would not go that route.

Edited March 6, 2009 by DB6

[yellowss7]

Thanks Sean. A 130hp engine for a grand is a good deal. I'm sure it could be loaded up with new Thottlebodies, hotter cams some porting, etc. for several additional grand.

 

You know the answer to the old question. "How much Horsepower can I get out of this engine?" Answer "How much money do you have to spend?"

 

Tom

[TheDingo8MyBaby]

Tom

I was thinking that myself.

I know the prices are lowest on the Xflow,then the Zetec with the Duratec thru the roof.

 

I would say the Zetec is generally cheaper than a crossflow, though probably not by much.

Edited March 6, 2009 by TheDingo8MyBaby