CHEAP LS TURBO TEST-EBAY GT45 vs SUMMIT S475

[Music] hey guys richard holden here let's talk turbos more importantly let's talk low block turbos on one side we've got our low buck ebay dna gt45 clone and on the other side we've got our kind of low buck summit racing s475 so which of our low buck turbos is actually best in this video we're going to take a look at a shootout i did between two low buck turbos the first one is one of my favorite ones it's the ebay gt45 and i call it an ebay this one was actually offered by the guys at dna but you can find it in a lot of places including amazon obviously ebay there's a lot of places online that sell this same turbo because it's very popular and very common the other one is an s475 turbo t6 s475 offered by the guys at summit racing now it's more expensive obviously than the very low dollar gt45 clone but it's also a lot more powerful and i know you might be thinking hey richard doesn't this sound familiar didn't you already do this video yes i did if you look back when i first started this channel back in december of last year and 2019 although it was a tough year for our family 2020s turned out to be even worse but i did it back in 2019 as one of the first videos that i put up almost a year ago now but if you look back it's only like two or three minutes long and that's not long enough to cover all of the data for this test it's an important test there's a lot of cool stuff here and i'm going to cover it all we're going to take a look at the power outputs we're going to take a look at the boost curves of both turbos we're going to compare them at the same boost level and show you all the things that i did wrong in this video let's check it out okay guys you can see i will have a lot of information to provide and that's the reason i'm redoing this test is because a two or three minute video just does not cover what happened when i compared the ebay gt45 stuff to the summit racing turbo both of which are fairly inexpensive but they're different turbos kind of for basically different power outputs not necessarily different applications because i might use the two interchangeably but i think i would do it if i was looking for different power levels on our n a combination and and right off the bat i'm showing you this power curve this is just a representation of what the n a power output would look like had i actually run it but we did not run the n a power motor the motor we did not run the motor n a before we added the boost i just put the turbos i just put the combination up on the dyno and started running it with the turbo combination right away because i only had one day to get this test done and doing turbo testing at different boost levels can sometimes be problematic but having run hundreds of of n a uh ls combinations i can tell you this is kind of what it would look like but anyway our test motor our na test motor had we run it uh i borrowed from david freiburger it was a 5.3 it had forged rods and forged pistons and it was a 5'3 block it had lower than stock compression ratio it had about a half pound or three quart or or a half point or three quarters of a point lower than stock compression because it had a dish piston in it it had a set of trick flow 205 heads it had a summit stage 3 turbo cam in it that was a 600 575 lift split a 231 234 degree duration split and a hundred and fifteen plus five lsa one of their stage two turbo cams works well we've run it on a lot of stuff and the reason that i haven't run this thing n a is we we had run it before uh on a with a different intake manifold but this was run with the factory truck intake manifold had i run it this is what our n a power output would likely be like it would be somewhere near 450 horsepower and this thing made 418 or 19 foot pounds of torque but let's get to the testing that i actually did here is the uh we ran the ebay gt45 turbo and i call it that but this one actually came from the guys at dna there are a lot of guys out there that offer this particular turbo it's very popular it's very common obviously it's made offshore and we've used it a lot i've had this particular turbo it has to be six or seven years now and we've run it a lot on a lot of different combinations if you take a look at the other video check it out it's right here i'll make sure to put it here and it's where i compare the ebay gt45 turbo on a number of different combinations including the 2.4 liter honda and all the way up to a big block 454 so we're running on a lot of stuff i've had it for a long time it's lasted a long time so i know that guys maybe have had problems with durability but on this particular one we haven't and it's worked fairly well although i have to say we have not run it out on the street for a long time shutting it off and running and then doing all the things that you do when you normally run in the vehicle i'm running out on the engine i don't think it's probably a little bit easier but here's what happened we also ran it with an air-to-water intercooler we had uh big injectors in this thing i think that they were oh i think that they were 120 pounds and i think we ran this thing on e85 so here's what happened we ran that's somewhere near 8 pounds 9.6 pounds 11.8 pounds 13 and a half pounds and finally a little over 14 pounds so our this the ebay turbo was able to convert our 445 horsepower motor into a 775 horsepower and we made 786 foot-pounds of torque now there probably was just a tiny bit left there might have been another 25 horsepower the most power we've ever made from this eba gt45 turbo is right at 800 and that's with you know you're you're trying to maximize the tune on it and turn the boost up as far as you can and that's kind of where it will be there's no a lot of guys ask me why don't you just turn it up to 20 pounds well the thing is it won't make 20 pounds it might make 20 pounds down here at 3 500 or 4 000 where it will support that that power level but it just what will happen is this thing as you turn the boost up and up and up and up it'll just start making 800 horsepower earlier but then it'll just carry that 800 all the way across because that's as much flow as that turbo will support so you can't just turn turbos up and definitely and have them keep making more and more power that just doesn't happen you can only do that when it has enough capacity to support that so this is what the ebay gt45 turbo but i want to show you what the boost curve did on these different tests and that way we can talk a little bit about the mistake i made when i did the testing so now we've taken a look at the power output of the ebay gt45 turbo on the modified 5.3 liter i want to show you the boost curve so this is the eight pound run as you can see i'm calling it an eight pound run but it's not it made 8.25 at the peak but then fell off down to seven pounds out at 6 500 so you can label that whatever you want i called it an 8 pound run and here's what happened when we went up and boost to the various different boost levels so as you can see from the boost curve they all have a falling this is a falling boost curve and right off the bat you should know that when i ran this we ran this with a manual wastegate controller it's just a simple bleed valve so there are two things happening here one an electronic controller would try to make a much flatter boost curve because it would keep adjusting the bleed orifice basically to try to maintain a given pressure ratio and they work very well we run one at west tech and have done this this was done back before we i think before we had that tc1 controller hooked up but i ran a manual controller the other thing that happens is the the manual controller is basically dependent upon the back pressure in the system has a big effect on what the on what the actual boost pressure is because you have back pressure in the system working to open the gate unfortunately so it's a differential between the the boost pressure that you're applying to the diaphragm and the back pressure working against that so it will open up basically at a different rate at a at the same setting on the on the boost controller so here the end result was because of the size of that turbo and its associated back pressure that we had a falling curve the other thing that creates a falling boost pressure curve is the flow rate of the turbo itself once you get to basically the flow limit of the turbo you'll have a falling curve because the turbo just won't support the power output but had we been able to had i hooked up an electronic controller we probably could have maintained judging by the curves given here somewhere near like let's say maybe we could have had a straight 10 or 11 pounds um or again because of the the flow rate of the turbo which we definitely would have got to at this power level we could have had a lot of boost like we see here in the low rpm ranges and then less out at the top because ultimately that's what would happen regardless of what kind of electronic controller we had on it we could have played with the electronic controller and more spring rate and you know you could try to do that to try to optimize this but ultimately you'll get to the on at least on this ebay gt45 turbo you will get to the point where there's just no more flow left and you will have a falling boost curve but this was these were all the boost curves offered by that ebay gt45 turbo and as you can see you know it'd be nice to have it be flat but this thing will only support a given amount of power so now let's take a look and see what happens when we put the larger summit racing s475 turbo on so now we've taken a look at the ebay or dna gt45 turbo and its effect on the n8 power output let's take a look at the summit racing turbo so i'll give you the specs on the summit turbo the summit turbo was an s 475 so it had a 75 millimeter compressor and an 88 millimeter turbine it was a t6 hot side so it was the bigger normally we run t4 so this is the bigger t6 and it had a fairly good size 1.32 ar so it had plenty of exhaust flow so it was more than enough for our combination and here's what happened we ran the summit turbo with the same air-to-water intercooler and obviously tuned this thing so here's what happened when we ran our summit turbo show you this at the different power levels and ours was a you can see from the photos ours was a polished housing so you know super fancy for the show car people now we were able to run the summit s 475 up much higher in boost and power because it would support that power level but as we'll see we'll take a look also like we did with the ebay gt45 turbo we'll take a look at the boost curves as well and we and you can see from the torque curve you can kind of get an idea um that we had fairly good boost response but i'll be able to show you that again we had the two 75 or a 45 millimeter hypergate wastegates but run with the summit turbo we ran the boost up and the power up all the way to 923 horsepower and peak torque checked in at 880 and we can take a look and kind of do a comparison of similar um boost levels for the two but unfortunately again because i had uh manual wastegate controllers and we'll take a look at the boosters on these on these summit power outputs it's hard to get exactly the same boost curve but i can kind of give you an idea we can talk a little bit about that about the difference between you know a big turbo and a small turbo what happens when they're running the same boost is there a difference in power and we can go over that a little bit but again you know this thing made plenty of power 923 horsepower and this s475 especially with the t6 housing certainly has the capability to make a thousand horsepower because that's kind of what an s475 size turbo is and this clearly kind of indicates that because this was only about 17 pounds and we had more left we could continue to go but let's take a look at the boost curves and we can talk about that we ran with the same um manual wastegate controller so let's see if we have the same issues as we had on the gt45 so here are the boost curves offered by the summit racing t6 turbo on our test motor seven and a half pounds that was eight and a half over ten showing thirteen 15 and then finally i think this is our 17 pound run so you can see the curve was flatter on the summit racing turbo and part of that is because we're again we're using a manual wastegate controller but the much bigger hot side and just general overall flow of this s475 compared to that gt45 clone we have more exhaust flow we have less back pressure so we basically have the controller is doing more what it should be and the back pressures have less having less of an influence although as we go up in boost pressure and go up in power output we have a lot more exhaust flow and we start to have a more of a falling curve at the higher boost pressures with the summit because again we're introducing more back pressure into it and all we have is a manual bleed valve so again had we had and had i run an electronic controller on this the summit certainly could have provided a fixed or a flat boost curve instead of dropping down to about 15 at the top it could have had a constant 17 and a half pounds because we know that the summit would support that and that would probably bring us really close to the uh to the 1000 horsepower mark as it is this this this thing made 923 horsepower but really did it at about 15 pounds and not at a not at 17 and a half pounds which again is closer to our formula if our n a power output makes 450 then you know at 15 or 15.2 pounds or so at the power peak it would definitely be right near 923 which is kind of where it was and that's what we would expect so these are the boost curves offered by the summit turbo and as you can see different than the boost curves offered by the the gt45 but now let's take a look at we'll compare maybe a couple of different boost levels if we can and see if we have some consistent or or some runs where we had the same boost or at least at some rpm or we can kind of compare the power outputs and you guys might be surprised so is the bigger turbo going to make more power you know at uh at any given boost level let's check so the question for everybody has to be in a comparison between the s475 and the ebay gt45 clone is well what do they do at the same boost level and as i said before it's hard to get these to be the same boost level unless i have an electronic controller which i did not do but what we can do is compare a couple of the runs where we had the same boost at least at one or two rpm points and we can kind of get an idea from there and it will correlate with every other test that i've run on turbo stuff and we'll go over that so let's take a look at this is about 13 and a half pounds and this is 13.4 or so depending on where you measure it but right here in the 4041 4200 rpm range they basically made the same power and as and as the summit turbo obviously made a lot more power getting up near 850 compared to 760 on the ebay turbo and the reason for that is because we had a following boost curve so what i'll do is i'm going to go ahead and show you that so we can kind of compare that and you can see for yourself that we did indeed make the same power at the same boost level so here's this one here's a summit so in this range of the 4000 you know actually 41 or 4200 where they crossed exactly they made the same power but when we start to see and this is kind of an anomaly in the boost curve for in the reading probably because the boost never dropped like that but as the summit turbo starts to make more boost it starts to make more power which we would normally associate with with any turbo higher boost equals higher power but these two turbos where they're making the same boost even at a fairly high rate of 13 and a half pounds which is a lot for that and a lot of power for that little ebay the gt45 clone they're making the same power and that's my point in all of this a lot of guys will say well yeah what about a name brand if i get a real garrett turbo and run it it'll make more power than these low dollar you know cheap imitation turbos the reality is that they don't and here's here's where they don't and here's where they do they will make if you run two motors or run the same motor n a you run it n a then run it under boost and control it with electronic controller like you're supposed to and you run two turbos one low dollar turbo and one high dollar turbo if you run the motor at the same air fuel and the same timing and and roughly the same back pressure if you can make that happen as well and you run the same boost pressure with an intercooler on it they're going to make the same power even if you have two turbos where one is if you can read compressor maps that they have compressor maps for both of them and one is at 63 percent efficient and the other one is at 66 or 67 percent efficient you won't see that sort of difference in the compressor map on the power curve it's just really hard to measure so the big thing is and this is what i want to get everybody to realize is the big thing is the n a power output add a turbo multiply it by the compressor ratio or not the compression ratio but if you get 14.7 pounds of boost and add it to an n a motor it's basically going to double the power output it will do that with a cheap ebay turbo and it will do that with a really high expensive name brancher well they both will do that and here's where they won't do that and that's if like in this case if you get to a point where the turbo size itself and that's the critical thing you have to have the turbo sized to do what you want it to do you cannot put an 800 horsepower ebay turbo on this thing and turn it up and hope that it will make a thousand horsepower it simply won't do that it's not physically big enough either on the hot side or the cold side to do that just like with any supercharger or any turbo it has to process a given amount of air it's got to go from one side to the other and it can't do that it's just too small you can't keep turning the boost up it will not support that so if you have one turbo that will support a big a high power level then it will be able to do that and the small turbo will not so that's an instance where not just a high price but a different size turbo will actually make more power than the small one but if you run both of them in a range where they both will support the same amount of power the power output of both of those turbos at the same boost level will be very very similar let's get to our conclusion okay guys before we discuss the conclusion in our comparison between our low buck ebay gt45 dna turbo and the kind of equally low buck s475 from summit racing i want you guys to make sure to tune in to this channel support the channel on tuesday nights where i'm having turbo tuesday where we normally talk about turbos some days we might talk about turbos and something else or some days we might just talk about something else but i'm calling it turbo tuesdays six o'clock pacific standard time that's california time and it's going to be later obviously on the east coast but make sure to tune in we're going to talk about cool stuff turbo stories all kinds of great stuff but what about the comparison between our low buck ebay gt45 turbo and our kind of low buck s475 the reality is it's hard to compare two turbos unless they're identical and these two turbos are obviously not these two turbos i normally recommend for different applications if somebody calls and says hey i want to make 500 or 600 horsepower what turbo should i go with i kind of steer them toward the ebay gt45 or something similar so the turbo the power output because that's usually my first question what kind of power are you trying to make and then the power outp output will dictate what turbo use if they're if they want to go with a thousand horsepower i will steer them toward the s475 like the summit racing one or a 7875 gen 2 like i have from byron over at vs racing something that's sized in that range because that turbo will support a thousand horsepower the gt45 will not but a lot of guys ask and they kind of ask the same question why can't you just turn the boost up on the gt45 and just turn up to 20 pounds the reason is because on any kind of reasonable ls application that gt45 will not support 20 pounds it certainly won't support 20 pounds out at the power peak and we covered that it will only flow enough air basically to support about 800 horsepower that's kind of the limit and even that is getting like into the unhappy spot on this turbo so i wouldn't recommend it for an 800 horsepower application although there are guys out there doing it now if you want to make more power than that step up to a bigger turbo like the s4705 turbo and you can make upwards of a thousand horsepower the other question that a lot of people get to and we might cover this on turbo tuesday also is i wanna i've had guys that sell turbos that tell me if you put this turbo on you're gonna make more horsepower per pound of boost and that's nonsense because the turbo is not going to do that what dictates how much power you make per pound of boost is the power output of the n a motor obviously the turbo has to be sized to also do that so if you have a 500 horsepower motor and you add 14.7 pounds of boost you're going to make an extra 500 but if you only have a 300 horsepower nn you had 14.7 pounds of boost you are only going to make 600 or another 300 horsepower so the n a power output of your combination dictates how much power you make per pound of boost but the turbo also has to be sized to make that power so if we have a little gt45 and it won't support a thousand horsepower you can make more horsepower per pound of boost with the s475 but only at a higher power level arbiter holder guys make sure to like share subscribe ring the bell do all that stuff more testing coming up

Channel: Richard Holdener

Views: 162,708

Rating: 4.9165931 out of 5

Keywords: s475, ebay gt45, summit, racing, turbo, intercooler, ls, 5.3l

Id: cY9lAI9vnF4

Length: 22min 45sec (1365 seconds)

Published: Mon Dec 07 2020