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I need to block a few coolant passages of the oil cooler or inside some sort of restrictor ring -

either split the coolant flow (to bypass the Laminova) or fit it in the heater circuit with a flow-restrictor in the pipework?

another possibility is to make a restrictor-ring that fits the Laminova core that blocks flow through the outer channels BUT. I think this will only slow heat exchange from cold as the aluminium will transfer once up to temperature :unsure:

the last-resort is to machine some of the fins from the Laminova's core (oil-side) BUT once removed they cannot be replaced...

personally I'd leave as is, ~95* isn't too hot or cold(y) (this also is dependant on temperature sender / gauge accuracy & where the sender is...)

Rich.
 

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Discussion Starter · #183 ·
Oh those numbers sound about what I’m thinking too Scotty, but for the sake I’m gonna go for my ‘dream / pie in the sky’ figures:

242bhp at 7500rpm / 184 ftlb at 6000rpm


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I really loved reading/following this. Thank you so much for taking the time to write this up.

I am super interested in the calculations you have done in the engine development. Any chance you would be so kind as to show your working a little bit? Where did yo get the information?


Thanks again
 

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Discussion Starter · #185 ·
Hi JRB, I gleamed most of my practical knowledge from reading books on the subject and talking to engine builders in my local area. You'd be amazed how nice to engine building community regardless of engine design/type (I've used so many 'tricks of the trade' in my engine build which I learned from a gentleman double my age messing with V8s & pinto engines!). In terms of calculations, I have performed pages & pages worth for this engine, I'm happy to talk you through a specific point if you'd like? I wouldn't like to try and type all of them on here as quite frankly it would take me ages!

The dyno session was an incredible day, it was super hot at 26 degrees outside (IATs were roughly kept at ambient throughout) and really sunny, lovely day for it really. Myself and Dave at Canems ECU had a good 30 minute chat before we started the tuning session, explaining what I'd done to it and after driving her for 100+ miles running in I explained some of her issues (such as part throttle stumbles / excessive overrun etc).

We go her strapped to the dyno and the tuning began. The first pull was very rough, only to 5500rpm and she still made 193hp - After looking over the fuel flow demand we knew this engine was strong so Dave continued to get her dialed in and smoothed out (Just fuel mapping to start with). After the fueling was sorted, I seem to remember we were roughly 233bhp / 185ftlb which was promising news, but the timing map was very conservative so Dave started to play with the timing maps next.

This is where it got extremely interesting, when we started to play with the timing curves it was obvious this engine is very sensitive to timing, not from a knock threshold perspective but actually where it wants to be (The window of good performing ignition advance was quite narrow). We did a blanket 4 degrees advance across the board to see what the power curve looked like and it jumped to 246bhp / 198 ftlb for peak numbers but it actually lost power in other areas so we were getting ever so closer to the sweet spot she wanted. Finally, after adding/removing timing at pretty much all points in the power curve we ended up with our final figure for the day:




she did very well indeed, pulling 267bhp at 7100rpm and 204ftlb at 6500rpm for peak figures. What's more impressive is that she has over 140ftlb torque from 3000rpm onwards.

For comparison, on the same dyno and corrected using the same software package, here's my stock bottom end 211bhp engine compared to the 2.0 long rod built engine:




the new engine is pretty much better everywhere! some people say that long rod engines won't produce as much bottom end torque than the standard rod ratio but in this instance, the increase in CC has meant I have kept the bottom end power but helped the engine breathe better at the higher RPMs and less frictional losses = more power up top.

I'm not done with this engine just yet, we still need to mess around with cam timing & intake trumpet length which is for another dyno day in the future - for comparison when I did the same second day with my stock bottom end engine I gained another 10bhp & 5-6ftlb so I reckon theres more potential to be had.

The dip in the torque curve at 4000rpm is most likely cam timing / tuned lengths in their negative sequence - this will get ironed out as best we can next time on the dyno during intake length & cam timing tuning.

As expected, the exhaust manifold is restricting power beyond 7000rpm and considering the power level she is achieving the jenvey 45's could also be the restriction (Ideally you want 48's beyond 60bhp per cylinder).

Overall very impressed with the this little BP, she runs like a smooth sowing machine throughout the rev range, feels like a race engine should do, love it!

the car is currently 600kg, 267bhp so its around 445bhp per ton - very fast indeed!
 

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Discussion Starter · #186 ·
Overdue update - yet again! (I don't any better at this blogging business!)

I managed to enjoy what was left of the year, season wise, with the car and getting used to the new performance and ironing out the niggles. The first niggle was I had a slight oil weep from one of the AN10 fittings on the sandwich plate which was easily resolved

The first big issue I'm finding is the rear tyre treads is literally ripping off the tyre's carcass! The problem is, I drive normally/gentle to moderate until the engine is upto temperature both from a coolant & oil perspective like you should. But, with the car being so light, the tyres don't particularly heat up at <60 mph / slow corner speeds / light acceleration so when the engine is ready to have some fun the tyres are not! So what happens is with the 195/50/15 R1Rs, I can give it 80-100% throttle at 35-40mph in 2nd gear and she'll just spin the rear tyres (literally feels like clutch slip its that instantaneous) and because she spins them when cold the tread tears off at the water relief cuts.

To sort this, I have ordered 205/50/15 R888R's for the rear and 195/50/15 R888Rs for the front (Fresh rubber as the R1Rs still have 90% tread left but the rubber will have hardened due to heat cycles). I'll also look to mess with the tyres temperatures once fitted to get them into the their sweet spot.

On the engine front, I wanted to further understand the engine's torque curve (Mainly to improve my knowledge and also assist with my engine development program). To do this I knew I needed the capability of a steady state dyno or in other terms a load bearing dyno (Hub dyno). After a quick google search, I found a local one to me at Garyspeed performance in Doncaster so after a quick phone call I got myself booked in - sadly I didn't have enough time to spend the day there due to other commitments but I managed to get a 1 hour slot!

So the first step was getting the wheels off and getting her bolted up, these dyno's are amazing bits of kit - I can't remember to capacity of this dyno specifically but I'm pretty sure it was near or over 1000hp so you can imagine all the hardware & hub adapters are pretty beefy!




Then it was time to get the car warmed up and ready for some pulls & steady state checks. The first thing we did was hold the engine at specific load points as I wanted to see/hear what was happening at specific RPM points. the first was the torque dip at 4000-4300rpm, you could pretty much hear the excessive reversion occurring which was quite something (I didn't think it would be so obvious) which definitely proved that the intake & exhaust lengths were completely out of synchronisation and rather than forcing more air into the cylinders, it was actually drawing exhaust gases in instead!

The other main notable point was doing a steady state hold rpm of 7000rpm - Firstly, this is bloody terrifying! your sat still with the engine literally barking its head off - fantastic! Interestingly though she made more HP at on a steady state hold, from memory around 260-263bhp but it proved that the engine was very happy & the AFRs were spot on. After the steady state points were done, we decided to do three power runs which were all done the same coolant & oil temperature to see how consistent the engine is as I have always wondered how consistent engine's are power production wise. It also provided me with an non-smoothed dyno chart which would help me to identify where harmonic boosts / exhaust length tuning points are actually occurring compared where I think they should be happening.

So firstly, here is the wheel power chart (No correction, just actual power/torque at the hubs)





And the corrected dyno chart (this should be roughly close to Inertia based dynos at 16% correction)





Overall, I just love this little BP! Its performing really well, doing exactly what I wanted it to do and is currently limited by its exhaust manifold primary diameter (Its 1.63" but this engine needs 1.75" to make power higher up) and the 45mm jenvey throttle bodies are also a limiting factor (more top end with 48's but less torque below 5000rpm plus I'd need +2mm intake valves to really make the 48's work correctly).

So plans going forward, get the tyre situation sorted and stop her spinning up the rears in second/third gear so she's actually 'fast' again below 80mph!
 

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Really interesting thread and wish I knew half as much about engine design and performance.

Have you thought about adding a couple of tyre temperature sensors, I think AIM do a kit that isn’t too pricey. Maybe possible to bond them to the inside of rear arches, then you could find out at what temp the tyres “turn on”


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Discussion Starter · #188 ·
Hey Miked5,

That would be a really cool solution, I would definitely go that way if I was going to do more track work with the car but If I'm perfectly honest I'm struggling for time as it is so I reckon It'll be a case of choose a cold tyre pressure, drive the car to warm the engine up then pull over and measure tyre temp with my IR gun. If the tyre is too cold, reduce tyre pressure (more friction/drag/load on the tyre to turn) and perform the same test until the tyre is in an acceptable temp range.

these little caterham style cars do tend to be sensitive to tyre pressure, more so than most cars ( I assume its due to their weight & suspension setups but I don't actually know the reasons!).

I've seen someone using a michelin App on their phone with a set of 'connect sport' michelin tyres which have a sensor built into the tyre (or maybe a modified version of one of those TPMS valve things most modern cars used for on-board tyre pressure measurement). Must be really cool to have live tyre temp data in car during trackdays, bet it would make you feel like a race car driver haha!
 

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Yeah I agree for a track car it would be an ideal solution but a bit overkill for driving on the roads haha

Yes I’ve found that aswell on my GBS Zero, I run Nangkang NS2R at 18psi and this seems to be good although I’ve only done a couple hundred miles so far. I think the mass of the car has a big effect, normal driving just doesn’t put enough energy through the tyres to really get them warm.


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Hi,
Excellent results I expect the engine pics up really fast too.

I have finally got myself a donor engine.
I know you have now got over 100 thou head skim and 85.5mm bores.
Can you let me know what your piston spec is ?
I know its a cheeky ask as you have done loads of work on the engine.
I am planning to de stroke the engine to drop the capacity and want to put the small end higher up in the piston and fit longer custom rods. I am only trying to drop the capacity down to 1796 using 85mm pistons.
Cheers for any advice / help
 

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Discussion Starter · #192 · (Edited)
Really good results there, any videos of it running on the dyno?

Short term tyre solution, more weight over the rear wheels....better eat a few pies!
Yes I do have a couple of videos, the Dyno operator was very kind and took one with my phone from the rear of the car during the pulls! I'll see about uploading it onto youtube shortly (y) I definitely do not need to eat more pies, otherwise I won't fit in the dam seat! :ROFLMAO:

Hi,
Excellent results I expect the engine pics up really fast too.

I have finally got myself a donor engine.
I know you have now got over 100 thou head skim and 85.5mm bores.
Can you let me know what your piston spec is ?
I know its a cheeky ask as you have done loads of work on the engine.
I am planning to de stroke the engine to drop the capacity and want to put the small end higher up in the piston and fit longer custom rods. I am only trying to drop the capacity down to 1796 using 85mm pistons.
Cheers for any advice / help
Always nice to be working with a donor engine, not the one you need to race with :D So in terms of head/pistons:

Head shave - .130 thou shave or 3.3mm depending on your preferred units
Pistons - 86mm custom JE pistons - FSR forgings / CNC lightening of the underside / +7cc dome from memory / 2618 forging / tool steel shortened pin with DLC / 1.0-1.2-2.8 ring pack at roughly 20% less tension than stock & different ring designs / piston skirt coating / horizontal gas ports

There's probably more to the pistons but I don't have the tech sheet nearby but long story short expect to pay around £450-500 per piston for the same spec as mine were by the end of it - I had to reduce my options as initially they were £766 per piston which I just couldn't stomach! (They always say making power isn't cheap or straight forward when staying N/A)
 

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Yes I do have a couple of videos, the Dyno operator was very kind and took one with my phone from the rear of the car during the pulls! I'll see about uploading it onto youtube shortly (y) I definitely do not need to eat more pies, otherwise I won't fit in the dam seat! :ROFLMAO:



Always nice to be working with a donor engine, not the one you need to race with :D So in terms of head/pistons:

Head shave - .130 thou shave or 3.3mm depending on your preferred units
Pistons - 86mm custom JE pistons - FSR forgings / CNC lightening of the underside / +7cc dome from memory / 2618 forging / tool steel shortened pin with DLC / 1.0-1.2-2.8 ring pack at roughly 20% less tension than stock & different ring designs / piston skirt coating / horizontal gas ports

There's probably more to the pistons but I don't have the tech sheet nearby but long story short expect to pay around £450-500 per piston for the same spec as mine were by the end of it - I had to reduce my options as initially they were £766 per piston which I just couldn't stomach! (They always say making power isn't cheap or straight forward when staying N/A)
Thanks for this information.
I have decided to go for 85mm Wossners to keep the cost down a bit. My head already has lost 80 thou so I will have to check the clearance with the HC Wossners before I do any more skimming.
I am still spending money on a new engine for the car in my Avatar at the moment. Its got a Billet counter balanced crank going into it with custom camshaft and followers, slipper pistons.
 

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Discussion Starter · #196 ·
So after fitting the R888Rs to the car, the performance has improved dramatically - I have a feeling the R1R's were hardened from heat cycling (I had done multiple track days & raod miles on them) and as such were just due a refresh. Initially I had the tyre pressures too high at 20 psi cold so the new tyres felt like I had no suspension fitted anymore and a trip the dentist to put my fillings back in was imminent :LOL: After re adjusting them down to 20 psi hot (I think it was maybe 17-18psi COLD from memory) the car was back on form - it drives fantastic with new rubber thats for sure!

I replaced both front upper control arm bushings as they had some slight play which could be felt through the steering wheel, it meant under hard load/hard braking the car felt a little skittish which it had never felt like that before so after changing those back to new units it feels amazing again.

This is potentially my final update on this build thread as I've put the car up for sale - Now on eBay, item number: 284806508548

Its been a long, hard decision as to whether or not to sell it but the timing seems right!
 
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