I'd be pretty bummed about those numbers too. See sig.. 14#s, 94 pump.. Extremely safe tune. I mean dynos can vary, etc.. but that seems pretty low to me.
Hellion Twin Turbo Kit
- Thread starter Mashburn94
- Start date
The hellion kits use the stock manifolds. Could that be why it reads low?
Nope. Ive built plenty of Hellion cars that made great power on stock manifolds. I bet there is something wrong with this car or its just a low reading dyno. But without the correct data its really hard to determine whats going on
The stock manifolds perform significantly better than most "turbo headers" as the cast iron holds in heat, even more so in a twin setup as the exhaust pulse doesn't have issue going into the single turbo.
ok. I was also thinking about how well the stock manifolds perform. These are two different setups but I remember buster running 8's with the hellion kit, single turbo though and trapped 154 or 156?
My buddy aj trapped 164 165 with the hp twin turbo kit but it has turbo headers. aj was on 25lbs or a tad more I believe? I know two different setups but I always questioned if the stock manifolds are holding these cars back with the hellion kit
My buddy aj trapped 164 165 with the hp twin turbo kit but it has turbo headers. aj was on 25lbs or a tad more I believe? I know two different setups but I always questioned if the stock manifolds are holding these cars back with the hellion kit
Turbo cars don't behave the same as N/A cars in terms of exhaust (or even S/C for that matter). You want velocity to get that turbo spooled up. Several people tried "shorty" headers on hellions and lost power. A TRUE properly sized turbo header may improve performance some but unless you are nearing that 900-1000 mark it would be next to nothing gained. In a single car it would be more beneficial, exhaust pulse timing can really help improve spool time, this is why many people switched to the twin scroll housings to help assist in this.
I have JBA shorties on my car just because I sold my stock manifolds way back when I did LTs.. Difference is probably negligible at my power level, but I am for sure not picking up a bunch of flow from the shorties vs the stock logs just from eye balling the two..
What about valve float? Hard to tell without a dyno sheet
I have to correct you. Assuming all parameters are the same besides turbos the larger turbo will always make more power even with the same boost levels. The reason being volume or cfm and that's why a larger turbo makes more power. If your reasoning was true noone would need to do any turbo upgrades or even convert over from a supercharger because your saying 10lbs is 10lbs as long as everything else is the same.
This will explain more.
http://www.rx7club.com/3rd-gen-archives-73/why-bigger-turbos-make-more-hp-same-psi-645551/
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Bigger turbos make more power when they are more efficient at moving the required air.
The reason you get a larger turbo is to move MORE air, when you aren't requiring more air it does not add power as you have not reached any additional CFM by the larger blower. In your theory a Fiesta ST could have a 76mm turbo on it and make more power with the same airflow. You are wrong, the 76 would be in a terrible spot on its map and would perform like dog crap, you have to read the compressor map and plot the correct sized turbo. Slapping on massive turbos will not create horse power as you claim. My reasoning holds true and is backed up by the "evidence" that you posted.
Bigger turbos make more power because they dont work as hard to move the same amount of air as a smaller turbo.compressing air creates heat.bigger turbo,less compression to move a certain amount of air.bigger turbos also usually have a bigger turbine wheel/housing.this reduces backpressure which increases an engines volumetric efficiency,more power.Its like porting heads,same amount of air with less effort.Yes bigger turbos wont be in their "sweet spot" but that doesnt mean they wont make more power.Theres 2.0L hondas out there with 80mm turbos,you think they give a crap about a compressor map?When you are dealing with a displacement challenged engine family like the modular,getting a 4.6 to make a certain amount of horses,you dont really need to look at a compressor map.compressor maps are used for someone trying to build a car with good mid rpm power.racing,peak/high rpm power is whats important.your not worried about sacrificing top end power for mid range power if your doing 5-8k rpm down the strip.just pick a turbo that supports the power you want and go,not too big,not too small.if you want to make 1200 horses,chose a turbo that will support 1300,so you dont have your turbo blowing a bunch of hot air trying to get those last 100 horses.when your stomping on the gas,racing,doing pulls,does low rpm power really matter?making good power at 4k is useless if your not there when your smashing.
A bigger turbo will blow cooler air and be less restrictive than a smaller turbo.AT THE EXACT SAME AIRFLOW,bigger turbo makes more power.
A bigger turbo will blow cooler air and be less restrictive than a smaller turbo.AT THE EXACT SAME AIRFLOW,bigger turbo makes more power.
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I don't think you understand the basics of volumetric efficiency. VE has to do with more air being in the charge and the motor being able to move that air. The size of the turbine does not factor in to the amount of air in the cylinder until the turbine has been maxed out. Those "80mm 2.0 Honda's" still use compressor maps, those are insanely high revving high compression cars that use their compressor maps albiet at a higher point in the RPM and require that much air to be moved. People do not put MASSIVE turbo's on cars expecting them to get more poor. A properly sized turbo will be more efficient and have no change in charge temp between it and a turbo significantly larger. At the EXACT same air flow, a proper turbo will make the same power but with a better power band than a turbo that is larger. That is my point and in your post you've simply argued an undersized turbo will be out performed by a big turbo, to which I say... Duh.
Turbine size DOES factor before AND after its maxxed.Change the turbine housing to a bigger one in ANY turbo engine and theres a 99.9 percent change there will be an increase in power without ANY other changes,why? Less restriction,better VE.bigger hotside on a turbo helps move that air,maxxed or not.
20 lbs/min from a smaller charger at 100 degrees DOES NOT produce the same amount of power as 20 lbs/min from a bigger charger running cooler at 90 degrees.engine receive the air colder,and spits it out easier,same amount of air.smaller charger has to work harder to move the same air,needs to compress more which causes hotter air.Its simple.Easy money.
You've completely missed my point and are attempting to prove me wrong by focusing on an extreme example. If I require X amount of air and my turbo is most efficient at X amount of air going to a turbo that is larger and X falls out of it's compressor map then a larger turbo will not do shit but hurt your performance across the power band. If I'm not RESTRICTING the air there is no additional heat. You are trying to argue a maxed out compressor or near maxed out that is generating heat because of it's inability to move air to a large unit that doesn't have a restriction. Heat is a by product of inefficiency if there is no wasted energy there is no heat. In a situation where a 76 will cover all needed flow with head room slapping a 88mm on there will not increase performance holding all else equal.
Were not talking about anything you just said.were talking more power.switch your turbine from 84mm to a BIGGER 86mm,nothing on the compressor side changed.tell me,why wont this make more power? Backpressure is going to be lower.it doesnt matter if your at 3k rpm or 7k.it will help VE.bigger makes more power.theres alot of threads on this topic and they all come back to the same answer
You clearly don't understand the first thing of VE or how an engine/turbo works. Go hang twin 76mm's on a 4.6 then an 80mm. Tell me at 3k if the twins will out perform the 80? It won't. If you are implying the engine can handle UNLIMITED rpm then you would be correct as the 80mm would then run out of the ability to push the air required through the engine. Under the curve where the engine makes power an 80mm will wipe the floor with twin 76's and make more power through the usable power band. A motor is a restriction, shoving more air into a restriction does not result into more air coming out the other side. If your motor was never a restriction then you would be correct but this is real life.
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