[roland2003]

Hi Guys, one of our customers has just sent us over a RR printout of his car on an independant RR.
The only mods are as follows:-
GTT Stage 3 head
Shrick cam
GTT17% pulley
GTT Re Route pipe
GTT/JCW hybrid filter upgrade
JCW injectors
Re-Map
Power..... 244bhp.
Prior to the head the power was 210bhp (on a different RR)

Car has stock intercooler and stock cat.
Apparantly the RR operator said this was easily the most powerful MCS he had tested & judging by the the graph the power was still climbing at the 6800 soft cut rev limit.
I dont know any more than this, but is looking good
Best Regards Roland GTT
GTT CNC MILLED HEADS With our heads not only do we mill out the exhaust ports (3D) but also the valve throats (again 3D). Im not aware of anyone else doing the latter.
The head was supplied to the customer for DIY fit with ONLY the milling parts done ,(normally we hand fettle them a fair bit more) and was fitted to the engine just about 'as it came off the mill'. With the fettling fully completed there may? have been even more power. .

[Ant FR]

something i have been thinking about for a while, how much does uprating the head and cams cost on its own. Although i feel now that with my car what is effectively a 230+ conversion, every bhp more i gain will cost me 100 pound or so to do.

[GTT 280]

Roland,

What are the main differences between your stage 2 and stage 3 heads? I appreciate the stage 3 head uses different valves, but what are the specific design differences?

Cheers,
K.

[Aberdeen Al]

I've been toying with getting some headwork done and in fact hoping to get a MCS head for nothing off a mate which I could use as an exchange unit so I would be interested in the cost versus power benefits of Stage 1, 2 & 3 heads.

[roland2003]

Hi guys, we also do a stage 4 head(even larger exhaust valves). This is now on our turbo'd MCS
Were also putting 3 angles on the valve seats, this too is all CNC interpolated
-See this car on the track at the Castle Combe Mini day in Sept.
Best Regards Roland GTT

[GTT 280]

Stage 4 GTT head.... interesting

[Bhozar]

Quote: Originally Posted by roland2003 (original)

Hi guys, we also do a stage 4 head(even larger exhaust valves). This is now on our turbo'd MCS
Were also putting 3 angles on the valve seats, this too is all CNC interpolated
-See this car on the track at the Castle Combe Mini day in Sept.
Best Regards Roland GTT

Is the stage 4 head useable on a standard-ish engine? Then if someone wants to upgrade to the turbo kit you do they dont need to buy that part of it?

[roland2003]

Ant...Hi, pm/telephone and we will work out some prices.
Al....Difficult to quantify the difference,but our car had GTT stage 2 when it made 273 bhp (240 wheel horse power). Just prior to taking our car off the road for the GTT300 turbo conversion,we put a GTTstage 4 on in pllace of the Stage 2 (no other changes). The car was definatly quicker particularly at high rpm,but its not a massive difference.
Bhozar.... This is a good point. As it happens we have a car coming down in 2 weeks for GTT stage 4 head & cam,with the intention of bringing it back again in 3 months for GTT300+ treatment. The car is a ex JCW challenge car,and I know its going to get some serious stick on trackdays. GTT300 uses stock head,our car with GTTStage 4 head is dubbed GTT350.There are other minor differences such as 3 bar MAP and even bigger injectors. This runs (and holds) 24psi to redline. GTT300 will run (and hold) 21psi to redline. Rev limit only slightly raised to 7200 which is 7000 'soft cut' . Stage 4 head on a mildly modded car is absolutly fine.
Best Regards Roland GTT
Karl.....stop it!

[Loui]

Quote: Originally Posted by roland2003 (original)

,but our car had GTT stage 2 when it made 273 bhp (240 wheel horse power).

Blooming eck roland at that you should have held the fastest quarter mile time for a M45 superchargd mini. Cause this was a fair while ago now. What times did you run?

[1320autos]

Nice 34bhp delta there Roland, has the customer got the 210 dyno sheet or can he overlay them.

[roland2003]

Hi Guys, we never dragged it with 270bhp. In fact the only time was when it had GTT220 (plus IIRC GTT Re-Route & GTT 63mm Throttle Body & early GTT prototype stage 2 head &cam ) at the pod with usual strong headwind 14.21 secs and 100mph.
I'll see if hes got the original plot before the cam& head were added.
Best Regards Roland GTT

[Revolution Mini Works]

what was the correction factor they were using on the Dynodynamics dyno?
If they dyno'd the car on a different dyno how can you be sure the delta was 34bhp?

It makes it difficult to compare apples to apples when there are so many variables in the equation. Never-the-less , I am excited to see what your turbo car will produce with the stage 4

[1320autos]

I put it down to age Roland, I know I do

Went to Santa Pod Raceway yesterday for our 'debut'runs.
Ambient 18degrees C.dry but cloudy,moderate/strong headwind plus uphill 3ft over the quarter!

SPEC GT TUNING LTD Cooper S:
GTT Cold Ram '360 degree' Intake, GTT Large Throttle body,
GTT Stage 2 Cyl Head &Manifolds ,GTT Modified OE header with one cat removed, GTT Re-route pipe on OE exhaust (deletes one silencer),GTT Camshaft(With adjustable timing) GTT 15psi pulley plus GTT Idler pulley,GTT knife edged Snoot,
STD intercooler, STD V37 Map,
OZ 17" Wheels with Road Legal tyres , ie Dunlop Sport DO1J (Hardest compound)
STD Diff, Pump fuel (UK97 Ron ,US 94?)
WEIGHT : STD less substitute wheels /tyres&rearseat out.
TIMES Best Quarter mile 14.21secs @99mph ,(also other 14.2's.)
Best terminal speed 100mph ,Best 60 ft 2.4secs
Regards Roland GT Tuning

[roland2003]

Well it was over 2 years ago,I knew I'd posted it somewhere. The clutch ((Standard)
was never the same after the pod. , -I'll stick to the racetrack .
I also occasionally have memory failure in the opposite direction aswell , I thought Tonys car made 210bhp prior to the GTT head & cam. It was actually only 204 (I'll put the graph up later), making a difference of 40 BHP not 34BHP!
1320 Autos.. ...BTW Is your RR able to measure (as opposed to adding a correction factor if required) the rundown losses?
Best Regards Roland GTT

[1320autos]

Congrats on finding an extra 6bhp and you didn't even have to get your hands dirty.

Its a Hoffman dyno and uses the TAT system to record all data etc etc

Chassis Dyno Software Chassis Dynamometer Software Rolling Road Software Inertia Dyno Data Acquisition and Control ,

it is a heartbreaker of a dyno and most of the time I hate it because what I think will work doesn't.

We made 19 runs experimenting yesterday and finally tuning the afc, I'm looking for more trq at the moment rather than peak numbers

[Revolution Mini Works]

any word on the correction factors used on this dyno?

[roland2003]

No,but a standard GP went on the same RR as this one a week later and made 202bhp (flywheel),which is 16bhp down on manufacturers claims,so it would appear this RR doesnt inflate figures .....possibly the opposite?
Best Regards Roland GTT

[Revolution Mini Works]

Quote: Originally Posted by roland2003 (original)

No,but a standard GP went on the same RR as this one a week later and made 202bhp (flywheel),which is 16bhp down on manufacturers claims,so it would appear this RR doesnt inflate figures .....possibly the opposite?
Best Regards Roland GTT

Thanks Roland,

I took my GP to the same dyno we dyno'd our head on and it only pulled 180whp to the ground, the car with my head on it pulled 231.9whp. It happens to be a dyno dynamics , by the looks of it they are NOT using a correction factor of 12%. Regardless its still a nice gain.

It's too bad everyone doesnt use the same correction factors as it's already difficult enough to compare apples to apples.

btw... how is the turbo car coming along? Have you got the new head on it yet?

[1320autos]

Here's the dyno results that Roland is referring to in his GTT stage 4 head ...50bhp? title thread. Is this the Surrey Rolling Road we were at the other Saturday??

[Revolution Mini Works]

Quote: Originally Posted by 1320autos (original)

Here's the dyno results that Roland is referring to in his GTT stage 4 head ...50bhp? title thread. Is this the Surrey Rolling Road we were at the other Saturday??

I don't see any dyno sheet..... is this word of mouth again?