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Zenas new engine


Delbert

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So far we have a head with large valves , 285 H cams , ported and flowed, PTP botty throtlers..... obviously an Emerald

 

when it comes to the Bottom end I seem to have 3 choices

 

1) Standard 1800 K bottom end , 7,200 rev limit around 180bhp say £400

 

2) Standard 1800 K bottom end, forged pistons, balanced crank and steel liners with a 8,000 rpm limit arond 195bhp say £700

 

3) Scholar Bottom end 1900 around 220 bhp at £1275

 

what is the difference in

a) acceleration 0-60

b) top speed

c) "Roadability as 75% of my mileage is on roads

 

I want 4 sec 0-60 and the ability to do 2000 miles in 7 days

 

When I get the mean reds the only thing to do is jump in the 7 ( with applebogies to Audrey)

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Drunk, Confused and once in a while you need to ask the experts.

 

 

I'm available for sarcatic comments, lightweight put downs or Decking quotations

 

But seriously I need to find out what I am getting for each pound I spend.

 

I need to balance the need for speed and the need for a new Chair and sofa

 

When I get the mean reds the only thing to do is jump in the 7 ( with applebogies to Audrey)

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Revs are lovely - but how often will you wring it out to the far end - which is where your peak power will be...? Actually, having just re-thought what it was like to go from a std. 1.6 (6.5k limit-ish) to my current engine (7.5k) - on the road, this *is* excellent because you suddenly can do overtakes in the Cadence-approved single gear (i.e. no gearchanges).

 

The 1900 should give you plenty of oomph low down as well though.

 

I'd suggest you either go for a or c. b is too close to c in terms of cost. C should also get you away from HGF through wobbly/low liners.

 

There is an alternative - but one that is probably not worth pursuing, cost-wise. Don't Scolar also do an 1800...?

 

          🙆🏻 🙆🏻 🙆🏻 🙆🏻 🙆🏻

Alcester Racing

7s Equipe™

🙆🏻 🙆🏻 🙆🏻 🙆🏻 🙆🏻

 

Alcester-Racing-Sevens.com


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you need 220 bhp for no reason other than you *can* have it. The hydraulic cams are your rev limiter so the only way you will get more power is to increase capacity *smile* *thumbup*

 

on the other hand

 

the ability to do 2000 miles in 7 days

 

Thats only 11.9 mph, so you may be better off with a pushbike 😬

 

 

 

here is C7 TOP

South Wales AO *thumbup*

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  • Support Team

A CSR200 is quoted at 3.7secs but I think you'd be hard pressed to actually match that figure on the road.

My 227bhp on Avon CR500s gave me a best of 4.0 secs at Dunsfold using one of those AP performance meters (not the most accurate but I am sure it gives a reasonable idea). My 60ft times at sprints are around 2.4 secs (some room for improvement there) using the same tyres. The guys on ACB10s are quicker.

The 1900 scholar engine with the mods you are proposing is a nice torquey engine (mine peaks at 167lbft), easy to drive round town and extremely rapid once you start using the full revs. As Myles says the Scholar conversion will make HGF highly unlikely. They do an 1800 as well but the extra couple of hundred pounds for the 1900 is well worth it.Think about your choice of pistons - I have the Pistal pistons as supplied by Scholar but these are a slipper design and should be checked every 2-3 years (depending on use - more frequently if lots of races/trackdays). I believe that Omega now do an 82mm piston which could be considered - talk to Oily.

Sticking with hydraulic tappets is a good idea as it eliminates the need to regularly check/adjust the tappets - it's also a significant cost saving!

 

Yellow SL *cool* #32

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Shaun, aren't the solid cam folowers shimmed?

 

I've never seen a shimmed cam need adjusting at low mileasges. Usually 50-60k will do. Even the old XK jag engines would go way over 60k before reshimming was needed.

 

Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here

You and your seven toThe French Blatting Company Limited

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Del, whatever you go for the other way to a faster car is to lose weight.

 

Get rid of spare and screen and get some carbon stuff fitted.

 

oops there goes the new carpet.

 

 

ed to put the "s" in "faSter" 😬

 

Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here

You and your seven toThe French Blatting Company Limited

 

Edited by - nverona on 20 Nov 2006 09:55:52

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Shaun,

Thanks for that its good to know I will not ruin ZeNA for her continental trips as that is the main reason I have her I think I have always known I'll end up at Scholar it just involves another few months of saving as I am determined to keep the stock engine so ZeNAS numbers match if I ever have to sell her.

I'll have to ring Oily at some time as he will prob be putting all the bits together but I waiting unn til I have somewhere near the budget

 

Dave,

I do stop for lunch 😬

 

Norm,

I've lost 2 and a half stone

 

When I get the mean reds the only thing to do is jump in the 7 ( with applebogies to Audrey)

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Del,

On Stunners my lardy SV (696kg inc driver) with 140bhp did repeated 0-60 of 5.1 at Dunsfold. My 0-62feet times were a couple of tenths quicker times than Shaun which shows I think that lower powered cars are often easier to get off the line quicker.

ChrisB with 180bhp in his whippet can do 4.1 0-60.

 

My performance goals are more based on 0-100 times as I think there show more differential in total car performance. I'd like to get to 10secs. That will need 200+bhp!

 

From your options the difference between A and C performance wise is very big for 'only' £900. I think you'll end up kicking yourself if you saved the £900 now and then had to spend £2000 in 6 months time to get the extra horses....

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Neil,

my lardy SV (696kg inc driver)
How much does the car weigh without driver? (Aren't I polite today *tongue*)

 

I must weigh ours, but I thought they only weighed 25kg more than a similar Chapman chassis car......

 

 

 

 

 

SeaView!!!!

😬 😬here *eek* *eek*

 

Edited by - Unclefester on 20 Nov 2006 19:41:56

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