Leeky 84 Report post Posted August 4, 2021 On 5/8/2021 at 10:41 AM, Varelco said: 280bhp seems to be the upper limit for the in tank fuel pump 280bhp seems to be deemed the safe limit on the twins. Above this you enter rod lottery, upgrades to the clutch and fuelling and running over the gearbox design limit of 250nm. Just thought i’d share that I’ve recently had a host of cooling upgrades done and a remap of my Cosworth Stage 2.2 Supercharger setup which made close as makes no difference 302bhp. Stock engine, stock fuel pump, stock coils and still factory front cat. Only engine upgrade being some cooler grade HKS plugs. Matt @ Cosworth was quite happy that I was perfectly safe running at this level and said I have plenty of margin left to stay reliable. I’m fully prepared for the fact that one day a rod may give up the ghost and i’ll need a rebuild but I just thought I’d share that he was happy that 300 was safe and no need to map power down to 280. 1 BRZ-123 reacted to this Share this post Link to post Share on other sites
MartinT 514 Report post Posted August 4, 2021 Good to know.Sent from my Oppo X3 using Tapatalk Share this post Link to post Share on other sites
BRZ-123 174 Report post Posted August 4, 2021 Just thought i’d share that I’ve recently had a host of cooling upgrades done and a remap of my Cosworth Stage 2.2 Supercharger setup which made close as makes no difference 302bhp. Stock engine, stock fuel pump, stock coils and still factory front cat. Only engine upgrade being some cooler grade HKS plugs. Matt @ Cosworth was quite happy that I was perfectly safe running at this level and said I have plenty of margin left to stay reliable. I’m fully prepared for the fact that one day a rod may give up the ghost and i’ll need a rebuild but I just thought I’d share that he was happy that 300 was safe and no need to map power down to 280.Very interesting. Are you on the smaller pulley and 2.5 inch manifold back exhaust? Sent from my SM-G781B using Tapatalk Share this post Link to post Share on other sites
Leeky 84 Report post Posted August 4, 2021 1 hour ago, BRZ-123 said: Very interesting. Are you on the smaller pulley and 2.5 inch manifold back exhaust? 3” Cosworth Midpipe/sports cat and Cosworth Catback. I haven’t changed the pulley and im running the 6PK2330 belt which I think would slip if I had the smaller pulley. But speaking to James at Amber he says it’s possible some of the later kits came with the smaller pulley instead of the larger one. I have a 6PK2315 belt to go on so at some point i’ll measure it to know for sure Share this post Link to post Share on other sites
BRZ-123 174 Report post Posted August 4, 2021 8 hours ago, Leeky said: Cosworth Midpipe/sportscat and Cosworth Catback. I haven’t changed the pulley and im running the 6PK2330 belt which I think would slip if I had the smaller pulley. But speaking to James at Amber he says it’s possible some of the later kits came with the smaller pulley instead of the larger one. I have a 6PK2315 belt to go on so at some point i’ll measure it to know for sure It has to be the smaller pulley, I reckon. The 300 mark is not crossed without smaller pulley unless the dyno you used, reads optimistic. Cosworth test car on standard pulley (with stock exhaust and with Cossie exhaust) , dyno attached. 265 with standard exhaust, 290 all in with Cosworth exhaust bits. Guidance must be changing over time as there are no known reported issues of engine damage with the Cosworth kit, so there is willingness to up the limits a bit. Look at the Video from 2:40 and see what Matt says in 2016. If you have time listen to the whole thing. The Fuel pump change is something he recommends in his installation guide. TD do it on their stage 2 turbo kit. It is easy to find out though if your fuel pump is at its limits by simply checking AFR's , if the Calculated AFR and Measured AFR are in the same ballpark range then its fine, if measured is going way above calculated... then the fuel pump isn't able to cope and you are running lean aka need a higher flow rate fuel pump.... Stock components could handle 300, its giving that headroom and not running things close to its limit, that's all. Official Dyno attached. Since yours is an Auto car i believe, the transmission is also at its limits and will benefit from fresh fluid and trans cooler too. Presumably, in your cooling upgrades, you got that done. Sent from my SM-G781B using Tapatalk Share this post Link to post Share on other sites
Leeky 84 Report post Posted August 5, 2021 12 hours ago, BRZ-123 said: Since yours is an Auto car i believe, the transmission is also at its limits and will benefit from fresh fluid and trans cooler too. Presumably, in your cooling upgrades, you got that done. Actually the Auto box is much stronger than the manual and can handle more power. Only issue with the auto is it gets quite hot. Yes I now have a Stark Performance cooler fitted with fresh fluids. I just took a vernier to my pulley and confirmed it’s definitely the smaller 63.5mm one. I just need to decide whether to try and find someone with the larger 70mm pulley to swap with or be prepared for the possibility of a bent rod followed by a rebuild. Share this post Link to post Share on other sites
BRZ-123 174 Report post Posted August 5, 2021 Surprisingly quite the opposite actually. The Auto box is much stronger than the manual and can handle more power. Only issue with the auto is it gets hot and I now have a Stark Performance cooler fitted to control the heat.Yes, my apologies. I did not mean torque limits but heat limits and hence my mention of a transmission cooler..Sent from my SM-G781B using Tapatalk 1 Leeky reacted to this Share this post Link to post Share on other sites
Mark@Abbey M/S 235 Report post Posted August 5, 2021 1 hour ago, Leeky said: Actually the Auto box is much stronger than the manual and can handle more power. Only issue with the auto is it gets quite hot. Yes I now have a Stark Performance cooler fitted with fresh fluids. I just took a vernier to my pulley and confirmed it’s definitely the smaller 63.5mm one. I just need to decide whether to try and find someone with the larger 70mm pulley to swap with or be prepared for the possibility of a bent rod followed by a rebuild. Quoting power gains on an auto is a little hit or miss, @Leeky what power did your Auto car record at the wheels please? Share this post Link to post Share on other sites
Leeky 84 Report post Posted August 5, 2021 33 minutes ago, Mark@Abbey M/S said: what power did your Auto car record at the wheels please? Sorry I dont know Mark. It was done on Ambers Hub Dyno (which I believe are DYNOmite’s) and the results I have on paper graph are based on flywheel power calculations only. They are going to be sending me over the dyno video so I’ll hopefully be able to see the whp from this. Share this post Link to post Share on other sites
Mark@Abbey M/S 235 Report post Posted August 5, 2021 I thought they had a dynapck like we do. These dyno read at the hubs and flywheel power ss estimated EDITTED they have a dynomite. 1 Leeky reacted to this Share this post Link to post Share on other sites
BRZ-123 174 Report post Posted August 5, 2021 I thought they had a dynapck like we do. These dyno read at the hubs and flywheel power ss estimated EDITTED they have a dynomite.The key question we are debating is , is 300 bhp safe and reliable power (ignoring dyno differences) or are we playing rod lottery or affecting long term reliability. And does the car need supporting mods at that power- fuel pump, injectors. What's your view Mark? Sent from my SM-G781B using Tapatalk Share this post Link to post Share on other sites
Leeky 84 Report post Posted August 5, 2021 Lots of forums/tuners say different things about the FA20 rods. But I know lots of guys in the US are running 10psi+ on stock rods and aren’t having rods bending. And people are running 330bhp on the stock fuel pump so I don’t think it can be maxed out at 300bhp. Just my opinion but I suspect most bending rods are caused by poor fuel/low octane/bad mapping/misfiring/knock rather than boost torque/power levels. Going back to the Cosworth charger specifically I honestly don’t think it matters which pulley you use. Correct me if i’m wrong but the larger pulley is 0.5bar (7.25psi) and the smaller pulley is 0.6bar which is 8.7psi. So less than 1.5 extra psi. I think even with the smaller pulley and 8.7 psi boost we’re still well on the side of caution. I think as long as the engine is well maintained, in good health and running 99ron it should be fine as long as temperatures are constantly monitored and you dont go dumping the clutch doing 1/4 mile drag racing as that really is asking for a rod to bend. 1 BRZ-123 reacted to this Share this post Link to post Share on other sites
Subota Boy 402 Report post Posted August 6, 2021 This is all very interesting, especially to me as I have the smaller pulley waiting to be fitted. I just have to be brave! Matt said that his map (specific for my car) would happily adjust to the smaller pulley, but that I was using up the safety margin built in and should not take it on track or "dump the clutch" too often in a short space of time. Thanks to Martin for accommodating all this specific chat on his thread. 1 BRZ-123 reacted to this Share this post Link to post Share on other sites
MartinT 514 Report post Posted August 6, 2021 54 minutes ago, Subota Boy said: Thanks to Martin for accommodating all this specific chat on his thread. It's interesting to me, too, as Mark made a very safe map for my Harrop. I did consider replacing the fuel pump with a higher performance one, but awaiting further advice. 2 1 Subota Boy, BRZ-123 and Leeky reacted to this Share this post Link to post Share on other sites
Mark@Abbey M/S 235 Report post Posted August 7, 2021 On 8/5/2021 at 9:19 PM, BRZ-123 said: The key question we are debating is , is 300 bhp safe and reliable power (ignoring dyno differences) or are we playing rod lottery or affecting long term reliability. And does the car need supporting mods at that power- fuel pump, injectors. What's your view Mark? Sent from my SM-G781B using Tapatalk On 8/5/2021 at 9:19 PM, BRZ-123 said: The issue is the rods , people have lost motors at a lot less than 300bhp so as a tuner you have to look/tune on the safe side , The rods are powder forged and this adds a element of risk but the rods are the same as the FA-20 turbo motor in the late Imprezza so even Subaru are working these rods a little. 2 Leeky and BRZ-123 reacted to this Share this post Link to post Share on other sites
BRZ-123 174 Report post Posted August 7, 2021 The issue is the rods , people have lost motors at a lot less than 300bhp so as a tuner you have to look/tune on the safe side , The rods are powder forged and this adds a element of risk but the rods are the same as the FA-20 turbo motor in the late Imprezza so even Subaru are working these rods a little. Thanks Mark. So what do we consider as safe then Also I think the WRX FA20 engine is a 10.5:1 comp ratio and hence it can take more boost compared to our 12 5:1. Stock it makes 258 bhp out of memory but a lot more torque ( close to 400 NM). Sent from my SM-G781B using Tapatalk Share this post Link to post Share on other sites
Mark@Abbey M/S 235 Report post Posted August 7, 2021 boost isnt the issue it is cylinder presure that causes damage. peak cylinder pressure is at max torque , torque versus rpm is the issue that causes rod damage 1 BRZ-123 reacted to this Share this post Link to post Share on other sites
Jay Bamrah 29 Report post Posted August 7, 2021 7 hours ago, Mark@Abbey M/S said: boost isnt the issue it is cylinder presure that causes damage. peak cylinder pressure is at max torque , torque versus rpm is the issue that causes rod damage So when eveeyone says a gt86 can take 280HP and past that it’s the engine lottery do they actually mean 230lbs of torque ? Is 230 what you would call safe limit? Share this post Link to post Share on other sites
MartinT 514 Report post Posted August 7, 2021 Here's my torque curve again: 284nm maximum torque (209lb.ft for the metric challenged). The green/yellow curve is what the Rogue EL manifold brought to the performance over the red curve (TD UEL). Share this post Link to post Share on other sites
cliddell 9 Report post Posted August 7, 2021 Martin, I'm interested in your experience with the uprated coils. Do you think the the improved driveability is down to the uprated coils, or just due to new items vs old/tired originals? Cheers! 1 Jay Bamrah reacted to this Share this post Link to post Share on other sites
Jay Bamrah 29 Report post Posted August 7, 2021 9 hours ago, Mark@Abbey M/S said: boost isnt the issue it is cylinder presure that causes damage. peak cylinder pressure is at max torque , torque versus rpm is the issue that causes rod damage So are you saying that maximum chance of damage is at max torque (5000rpm) or when you’re full throttle at 2000rpm gear 6? 1 MartinT reacted to this Share this post Link to post Share on other sites
MartinT 514 Report post Posted August 7, 2021 Martin, I'm interested in your experience with the uprated coils. Do you think the the improved driveability is down to the uprated coils, or just due to new items vs old/tired originals? Cheers!The plugs that came out were in decent condition, so I would attribute most of the improvement to the Delicious coil packs. Sent from my Oppo X3 using Tapatalk 1 Subota Boy reacted to this Share this post Link to post Share on other sites
cliddell 9 Report post Posted August 8, 2021 13 hours ago, MartinT said: The plugs that came out were in decent condition, so I would attribute most of the improvement to the Delicious coil packs. Cool, thanks. I've had good experiences using high power coils on old skool, distributor based ignition systems before, but at least some purveyors of "internet wisdom" claim it's not worth it with COP packs unless pushing big power. Good to hear that's not the case. Another thing for my shopping list, and "little" job for Abbey at some point! 1 MartinT reacted to this Share this post Link to post Share on other sites
MartinT 514 Report post Posted August 8, 2021 1 hour ago, cliddell said: some purveyors of "internet wisdom" claim it's not worth it with COP packs unless pushing big power. I see this in my hi-fi forum a lot. "internet wisdom" appears to consist largely of people expressing opinions when they have no experience of the product! 1 SimonG68 reacted to this Share this post Link to post Share on other sites
BRZ-123 174 Report post Posted August 27, 2021 It's interesting to me, too, as Mark made a very safe map for my Harrop. I did consider replacing the fuel pump with a higher performance one, but awaiting further advice.https://www.counterspacegarage.com/products/engine/ecu-programming-kits-ecu-tunes-maps/csg-spec-tuning-toyota-86-brz-frsCSG are quote popular in the USA for our cars and they recommend not to change fuel pump as aftermarket is not as reliable. Please see link above. Sent from my SM-G781B using Tapatalk 1 MartinT reacted to this Share this post Link to post Share on other sites