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Posted

Hiya,

 

Reinald just made me aware about this forum which I had totally overlooked...

 

I'm Nikolai from Germany. I currently have 2 Spitfire 1500s, one for racing and one for the road (to be sold soon - time only allows working on one).

I race in the Triumph Competition Series (championship win in my 1st season 2005, loads of class wins since then ;-) ) and share the garage with Reinald.

Together we are continuously debating performance optimization for the Spits and try various routes.

Hope to get some fresh thoughts from the crowd here as well (actually - not neccessarily from everyone.... ;-) )

 

Here's the spec of my race car as dynoed September 2008 right before the Eifelklassik race on the Nordschleife (where Murphy prohibited a proper start...)

colour: powder blue

weight: ca. 690kgs (WIP...)

cam: TH7 from APT (OMG!!! - one of those non-functioning, flat-spotting, evil pieces of xflow cr*p!!!)

rods: standard - but you could use them as a shaving mirror

pistons: AE TR6 +0.020 (Spitfire bore +0.060) - chosen for price and weight

crank: standard, nitrided and balanced

Flywheel: Bastuck lightweight (so light that I managed to bend the piece of sh*t with a std. clutch - now upgraded to proper Fidanza)

block: std., decked 4mm to accomodate the TR6 pistons

head: fairly modified ;-) with 39mm inlet and 30.5mm exhaust, 7mm stem with lash caps

C/R: ca. 12.0:1

Rockers: 1.65 Titan Rollers

Springs: Isky/APT with Schrick titanium caps

Exhaust: Phoenix 421 with enlarged tailpipe (57mm)

Carb: Dual Weber 40 DCOE / 34mm venturis

power band used in races: 4500-7000

 

The car employs custom-made Summres-Brothers back axles (one broken axle at the Tarzen turn in Zandvoort tought me a lesson) but still runs with Spitfire brakes (lighter than GT6).

Wheels are race steel wheels from US - lighter than Revos and (in my opinion) much more mean-looking than the ordinary Minilites.

 

That package brings

165Nm at ca. 5200rpm

141hp DIN at ca. 6650rpm

(and at time of dynoing the engine was end-of-life, having only 8.5bar compression on cylinder 3 due to damaged cylinder wall (it had tried to eat a valve guide some months before...)

 

I'll upload the dyno sheet to the web later today.

For those who are interested to compare figures here some infos on the RR used

Manufacturer: CARTEC

Built in 2004 (installed early 05)

fully computer controlled

re-calibrated every 2 months

This is the by far (5-8%) lowest reading RR I had my car on so I am pretty sure the numbers are not inflated. Furthermore the shop is no speed shop but primarily an "ordinary garage" that managed to get a reputation within the racing crowd for being competent in setting up carb'ed cars very well.

 

For 2009 2 major changes have been carried out and the RR session is end of march (if the fluids in the freshly assembled engine decide to remain where they ought to be ;-):

- custom 421 exhaust (same as Reinalds, we have had the lenghts calculated by Burns for a rev range from 4-7k)

-  custom grind APT camshaft that is slightly shorter than TH7 at the seat but has much higher acceleration rates (google for Crane Tight Lash profiles). Goal was to extend the TH7 power band by 500rpm at the low end. Curious to see the results...

 

Picture of my car (nice) and myself (no comment ;-) )can be found here

http://www.triumph-competition.de/fahrer/aktuell/Nachname/aufsteigend

 

A little video from a Hillclimb we did in 07 is available here:

http://www.100octane.de/cms/content/blogcategory/27/43/

(search for "spitfire" - direct linking to the video itself is prohibited by the site's webmaster)

 

Looking forward to "talking rubbish" with you - and hopefully meet the one or the other on a racetrack.

 

cheers

niko

 

Posted

That looks like a very nice car. Welcome here Niko - sure you will enjoy this forum. I am curious to why your car is 15 kilo lighter than Reinalds?

 

Cheers

¨Nick

 

Posted
Hiya,

 

 

cam: TH7 from APT (OMG!!! - one of those non-functioning, flat-spotting, evil pieces of xflow cr*p!!!)

 

 

 

Mine was horrid from 3700-4200 or so?

 

I smoothed this area by retarding my ignition system (ECU)...I ran advance that was best from idle speed to the main flat/rough area, then retarded the map/ignition backwards by 3-4degrees within the bad area and started to increase the advance again at 4200...others have done similar things. Of course you need ECU not distributor.

 

I found the TH7 ok at the top-end on my 1300, power was good from 4800-7300, could rev to 7800 if needed. (118HP (flywheel) max. 33mm chokes in DHLA40C Dellorto carbs. This was a road-engine.

 

Posted

Hi Dave,

 

I'm pretty shure, the APT TH7 has nothing in common with the Kent TH7 than the basic valve timing. Lobe profile might be quite different, even though I never reverse engeneered the profiles. Even the blanks look a lot nicer than then Kent ones that I've seen - made more solid and more precise.

 

Reinald

Posted

Ok, I notice the 3500-3700/4000-4200 spike on all TH7 (254) KENT cams....

 

The 264 seems to have a wider spike than the 254(TH7)...The TH6 has one also, less than TH7. TH5 has a spike too, smaller than the TH6...

 

Makes sense? These cams are rubbish.

 

As you say, the timing is the timing, the shape of the lobe can be quite different from one "grinder" / manufactoring company to another!

 

Numbers are meaningless.

Posted

Hi,

 

have to disagree on the (APT) TH7 being rubbish (in my 1500).

Works perfectly well for me as my rpm band is 4000/4500 - 7000 (where the TH7 pulls strongly). The flat between 4000 and 4500 is what I want to get rid of with the new custom grind cam.

THX for the tip re. ignition retard, but unfortunately programmable ECUs are banned by regulations... ;-(

 

cheers

niko

Posted

want to put my 2cents in for APT. they are a very knowledge shop with an equally vast background and customer base. have been developing  BL and BMC race engines since those concerns existed and i am a satisfied customer. they are located in Riverside Ca. (east of LA) formerly the home of very good race track at which the NASCAR oval racers tried to compete on every year.also in response to several posts about rolling road figures and what it takes to go way beyond what BL designed. there was a 60's TV show Dragnet  a cops pysdo reality show.the dead pan lead cop would always say to an emotional witness "just the facts please"

  • 3 weeks later...
Posted

Hi Andy,

 

any particular idea you have in mind?

Mine are primarily "stolen" from a certain Mr. Vizard...  ;)

(have to admit one idea is stolen from Jon: "go on a diet")  ;D

 

cheers

niko

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