MegstuBMW Posted June 23, 2020 Author Share Posted June 23, 2020 On 6/22/2020 at 11:25 PM, glanzadude said: What happened to the front off the car? Great build tho Driver in front braked hard and I haven't seen it in time Quote Link to post Share on other sites
MegstuBMW Posted September 7, 2020 Author Share Posted September 7, 2020 (edited) Edited September 7, 2020 by MegstuBMW Quote Link to post Share on other sites
MegstuBMW Posted September 7, 2020 Author Share Posted September 7, 2020 Quote Link to post Share on other sites
Sam44 Posted September 8, 2020 Share Posted September 8, 2020 (edited) Are you running any of the head braces used with the factory engine, and what engine mounts are you using. Did you get the engine deck skimmed/checked. Also which head gasket is this you have used, boost pressure and fuel pump. I can't see the rpm at which the hp starts to fall off?. For hp to be hit like this before 6000rpm I'd put my money on fuel delivery rates (fuel pump, fuel rail, filter) if it's the standard pump I'd try this first. If it's after I'd say valve bounce/wobble. Possibly I see you have uprated valve springs. The decate pipe after the turbo I'd say go much bigger diameter as well, this help reduce back pressure, I call it the turbo dump pipe. Looks good I've just had a catch up on the build. The intake looks good for that power, what exhaust diameter are you running and turbo. Torque will drop off after peak head flow rates as stated below but you should be able to keep hp figures building or at least level off till redline. Nice work. Edited September 8, 2020 by Sam44 Quote Link to post Share on other sites
RobSR Posted September 8, 2020 Share Posted September 8, 2020 The drop off is common with stock style cams, usually after around 5500rpm. Hope you get it fixed up soon Quote Link to post Share on other sites
Claymore Posted September 8, 2020 Share Posted September 8, 2020 (edited) 5 hours ago, Sam44 said: Are you running any of the head braces used with the factory engine, and what engine mounts are you using. Did you get the engine deck skimmed/checked. Also which head gasket is this you have used, boost pressure and fuel pump. I can't see the rpm at which the hp starts to fall off?. For hp to be hit like this before 6000rpm I'd put my money on fuel delivery rates (fuel pump, fuel rail, filter) if it's the standard pump I'd try this first. If it's after I'd say valve bounce/wobble. Possibly I see you have uprated valve springs. The decate pipe after the turbo I'd say go much bigger diameter as well, this help reduce back pressure, I call it the turbo dump pipe. Looks good I've just had a catch up on the build. The intake looks good for that power, what exhaust diameter are you running and turbo. Torque will drop off after peak head flow rates as stated below but you should be able to keep hp figures building or at least level off till redline. Nice work. Snaffled some graphs from the youtube vid. Top shows all power runs, bottom shows first 2 runs with rpm as reference for top graph: Assuming its up to date, the thread mods list looks like: Block was decked, Head skimmed 1.3mm, Athena MLS 1.2mm HG, Walbro 255lph + 560cc injectors, possibly 1.5bar boost, K04-023 turbo (couldn't find the comp. map) 60mm exhaust, adjustable intake cam gear and adjustable exhaust pulley (unknown settings). Edited September 8, 2020 by Claymore Quote Link to post Share on other sites
Sam44 Posted September 8, 2020 Share Posted September 8, 2020 What's the wastegate size. Are you running the standard fuel rail. Quote Link to post Share on other sites
MegstuBMW Posted September 8, 2020 Author Share Posted September 8, 2020 (edited) 13 hours ago, Sam44 said: Are you running any of the head braces used with the factory engine, and what engine mounts are you using. Did you get the engine deck skimmed/checked. Also which head gasket is this you have used, boost pressure and fuel pump. I can't see the rpm at which the hp starts to fall off?. For hp to be hit like this before 6000rpm I'd put my money on fuel delivery rates (fuel pump, fuel rail, filter) if it's the standard pump I'd try this first. If it's after I'd say valve bounce/wobble. Possibly I see you have uprated valve springs. The decate pipe after the turbo I'd say go much bigger diameter as well, this help reduce back pressure, I call it the turbo dump pipe. Looks good I've just had a catch up on the build. The intake looks good for that power, what exhaust diameter are you running and turbo. Torque will drop off after peak head flow rates as stated below but you should be able to keep hp figures building or at least level off till redline. Nice work. Not sure what do you mean head braces? All engine mounts I made from polyurethane rod, just cut off and grinded to fit in to original engine mount housing. Head gasket was Athena 1.2mm, 1.6bar boost, fuel pump WALBRO TIA 255 bolt on upgrade. From 6000rpm Nm is going down hill. My AFR is good, injector duty cycle does not reach 70%. Valve springs is upgraded, more than double strength compared to NA springs (not sure how it compares to 4E-FTE springs). Yes, intercooler piping, it is not big enough, good point. Exhaust diameter is 60mm, turbo is k04 from audi tt 1.8 (I know it is too small and that is my guess why power is falling in top end so much). Thank you for your support and ideas! Edited September 8, 2020 by MegstuBMW Quote Link to post Share on other sites
MegstuBMW Posted September 8, 2020 Author Share Posted September 8, 2020 6 hours ago, Sam44 said: What's the wastegate size. Are you running the standard fuel rail. Wastegate is integrated, using standard fuel rail. Quote Link to post Share on other sites
Sam44 Posted September 9, 2020 Share Posted September 9, 2020 (edited) Yeh the fuel rail is quite restrictive also. To me it looks like exhaust back pressure and temps plus high end valve overlap. But at your hp the fuel rail will start to show it's flow potential. The standard 4efe and 4efte has head braces either side of the cylinder head. The cylinder head were it bolts to the block is a wedge shape leading to shorter and longer head bolts!!. It's common to for these to have different torque settings in the proformance world plus the added weight of the new bigger turbo kit on 1 side of the head. Are the arp bolts stretch bolts. Do you do a warm up final tightening torque down. A higher lift cam would be better as well I feel. Are you monitoring exhaust gas temperature. Loving the progress. Edited September 10, 2020 by Sam44 Quote Link to post Share on other sites
Claymore Posted September 9, 2020 Share Posted September 9, 2020 2 hours ago, Sam44 said: The standard 4efe and 4efte has head braces either side of the cylinder head. Interested in this as well, do you mean the braces for the catalytic converter and intake manifold to take stresses off the head? Or are these different ones to hold the head to the block? Any pics or diagrams? Quote Link to post Share on other sites
RobSR Posted September 9, 2020 Share Posted September 9, 2020 22 hours ago, MegstuBMW said: Not sure what do you mean head braces? All engine mounts I made from polyurethane rod, just cut off and grinded to fit in to original engine mount housing. Head gasket was Athena 1.2mm, 1.6bar boost, fuel pump WALBRO TIA 255 bolt on upgrade. From 6000rpm Nm is going down hill. My AFR is good, injector duty cycle does not reach 70%. Valve springs is upgraded, more than double strength compared to NA springs (not sure how it compares to 4E-FTE springs). Yes, intercooler piping, it is not big enough, good point. Exhaust diameter is 60mm, turbo is k04 from audi tt 1.8 (I know it is too small and that is my guess why power is falling in top end so much). Thank you for your support and ideas! You can fit a GT30 my friend and you’ll still loose torque after 5500rpm with the stock head/and cams. That’s where the main restriction lies. Standard fte fuel rail is fine, you can run 1000cc injectors at upto 5 bar pressure with no issues whatsoever. I think your issue is either head / block prep or you have been unlucky with the gasket. I’ve seen a few Athena’s fail like yours, I’d try swapping to a cometic, redeck the block and skim the head. Quote Link to post Share on other sites
MegstuBMW Posted September 9, 2020 Author Share Posted September 9, 2020 2 hours ago, Sam44 said: Yeh the fuel rail is quite restrictive also. To me it looks like exhaust back pressure and temps plus high end valve overlap. But at your hp the fuel rail will start to show it's flow potential. The standard 4efe and 4efte has head braces either side of the cylinder head. The cylinder head were it bolts to the block is a wedge shape leading to shorter and longer head bolts!!. It's common to for these to have different torque settings in the proformance world plus the added weight of the new bigger turbo kit on 1 side of the head. Are the arp bolts stretch bolts. Do you do a warm up final tightening torque down. A higher lift cam would be better for as well I feel. Are you monitoring exhaust gas temperature. Loving the progress. At this point there is no symptoms showing fuel rail limit. Maybe sequential fueling is helping. About head studs, I just used IRP instruction that came with studs, there was no mentioning about heat cycles or different torque settings, I just trusted that. I do not monitor exhaust temp or pressure, that is good idea. Quote Link to post Share on other sites
MegstuBMW Posted September 9, 2020 Author Share Posted September 9, 2020 3 minutes ago, RobSR said: You can fit a GT30 my friend and you’ll still loose torque after 5500rpm with the stock head/and cams. That’s where the main restriction lies. Standard fte fuel rail is fine, you can run 1000cc injectors at upto 5 bar pressure with no issues whatsoever. I think your issue is either head / block prep or you have been unlucky with the gasket. I’ve seen a few Athena’s fail like yours, I’d try swapping to a cometic, redeck the block and skim the head. I see, thank you for info Quote Link to post Share on other sites
Sam44 Posted September 10, 2020 Share Posted September 10, 2020 (edited) 11 hours ago, Claymore said: Interested in this as well, do you mean the braces for the catalytic converter and intake manifold to take stresses off the head? Or are these different ones to hold the head to the block? Any pics or diagrams? Yep the 4efe has the braces on the intake to the block and exhaust manifold to the block and the fte has the turbo to the block. The fuel rail information came from some of the lads that was pushing for 250hp+. The starlet I have came with a modified honda unit on it. Really enjoying the build I hope you get this sorted. Keep us posted. Edited September 10, 2020 by Sam44 Quote Link to post Share on other sites
MegstuBMW Posted September 10, 2020 Author Share Posted September 10, 2020 7 hours ago, Sam44 said: Yep the 4efe has the braces on the intake to the block and exhaust manifold to the block and the fte has the turbo to the block. The fuel rail information came from some of the lads that was pushing for 250hp+. The starlet I have came with a modified honda unit on it. Really enjoying the build I hope you get this sorted. Keep us posted. I think these braces is mostly to support intake and exhaust manifold from cracking-vibrating. I made one brace from turbo to block. Also intake manifold has one brace from intake plenum to cylinder head. Quote Link to post Share on other sites
Sam44 Posted September 10, 2020 Share Posted September 10, 2020 You would be surprised. the head bolts on the standard engine are stretch bolt design. They really do not need to deal with any stresses other than the combustion process. It's just a thought to consider. I believe what's happed to your head gasket is a common thing with these after a rebuild (highly modified). I'm building a forged 5e and working through the issues/errors. Like the different length head bolts. I've decided to go with studs. Quote Link to post Share on other sites
MegstuBMW Posted September 10, 2020 Author Share Posted September 10, 2020 5 hours ago, Sam44 said: You would be surprised. the head bolts on the standard engine are stretch bolt design. They really do not need to deal with any stresses other than the combustion process. It's just a thought to consider. I believe what's happed to your head gasket is a common thing with these after a rebuild (highly modified). I'm building a forged 5e and working through the issues/errors. Like the different length head bolts. I've decided to go with studs. Maybe you are right. By the way, I used 10mm IRP head studs. Quote Link to post Share on other sites
Sam44 Posted September 11, 2020 Share Posted September 11, 2020 (edited) On 9/10/2020 at 10:45 PM, MegstuBMW said: Maybe you are right. By the way, I used 10mm IRP head studs. Thanks for sharing the development. It is a strange thing that has happened to the head gasket especially the fact the studs have loosened off. Have the studs stretch at all?. If so there's an underline issue. Edited September 12, 2020 by Sam44 Quote Link to post Share on other sites
MegstuBMW Posted September 14, 2020 Author Share Posted September 14, 2020 On 9/11/2020 at 11:45 AM, Sam44 said: Thanks for sharing the development. It is a strange thing that has happened to the head gasket especially the fact the studs have loosened off. Have the studs stretch at all?. If so there's an underline issue. Not sure if studs stretched, I have already assembled everything back. Will upload updates soon. Quote Link to post Share on other sites
jiggaman_16 Posted September 23, 2020 Share Posted September 23, 2020 On 9/14/2020 at 11:23 AM, MegstuBMW said: Not sure if studs stretched, I have already assembled everything back. Will upload updates soon. Interesting build. Keep us updated plz Quote Link to post Share on other sites
MegstuBMW Posted October 11, 2020 Author Share Posted October 11, 2020 (edited) Edited October 11, 2020 by MegstuBMW Quote Link to post Share on other sites
Sam44 Posted October 11, 2020 Share Posted October 11, 2020 I'm really liking the wrap design. Nice styling. Did you get to the bottom of the power drop off. If I may ask what was the cam configuration on the first Dyno graph. Quote Link to post Share on other sites
MegstuBMW Posted October 11, 2020 Author Share Posted October 11, 2020 7 minutes ago, Sam44 said: I'm really liking the wrap design. Nice styling. Did you get to the bottom of the power drop off. If I may ask what was the cam configuration on the first Dyno graph. Thank you! Have not fixed power drop in high rpm, now I am thinking maybe bigger turbo would fix that. On first dyno graph, cam overlap was nearly non. I was on dyno after changing overlap and there is no noticeable difference (will upload photos soon). Quote Link to post Share on other sites
Sam44 Posted October 11, 2020 Share Posted October 11, 2020 Thanks for the replay. Are you running a ko4 turbo at present. Quote Link to post Share on other sites
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