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Rb20det s13 runs perfect but slower than a civic

Hey everybody, i just made this account because ive been browsing this site everytime i need to learn something about my engine(rb20det) and the info yall got here is incomparable to any forums in the US where its just a huge internet argument. With that being said i havent found anything on this forum that adresses the issues im having so here goes. 

I have a rb20det swap in my s13 running everything stock, its holding boost at 10psi, the wideband reads 11-12 on boost and around 15 at idle, the timing is set at 15* and everything appears to be running perfect except a little idle fluctuation from 680-780rpm and sometimes i need to hit the gas when cranking to start it. The major issue im having is my car is slower than my honda accord but seems to be running fine, i can feel the turbo spool and the boost comes on but its still very very slow. Any help would be greatly appreciated 

The new V6 Honda Accord has over 200kw IIRC, whereas an RB20DET had 158kw, and that's when it was brand new, not 20+ years old.

Your question is pretty vague bud without more details, but really it isn't hard to imagine your RB20 being slower.

@niZmO_Man it has the stock ecu and stock everything, ive been in a stock rb20det powered s14 and it felt much faster, mine pulls as hards as a single cam KA

@inmaniacmy honda accord is an old 4 banger i was just trying to emphasize how slow my s13 is lol something feels wrong fersure

Sounds like it behaves like its n/a. I sure u got a turbo in there?

jokes aside check if you don't have a boost leak or if ur turbo is dead. All i can think off. And AFM like nizmo_man said

@drunken0elf @iruvyouskyrine @niZmO_Man Timing is at 15* all spark plugs look perfect sandy color and coils look good. AFM reads 11-12 on boost and 14-15.7 at idle or low throttle. My boost gauge says it holds 10psi which sounds about right for the stock turbo. Could there be a boost leak or busted turbo even though the gauge reads 10psi? It really does preform like an NA engine but it holds 10psi on boost and about -18 vaccum at idle. It seems to rev slow under load as well, maybe driveshaft issue? There is a clunk from the rear sometimes when i shift or hit the throttle hard which i believe is my center support bearing but i wasnt under the impression that it would cause a massive power loss like this

Edited by Tortise240
4 hours ago, Tortise240 said:

@drunken0elf @iruvyouskyrine @niZmO_Man Timing is at 15* all spark plugs look perfect sandy color and coils look good. AFM reads 11-12 on boost and 14-15.7 at idle or low throttle. My boost gauge says it holds 10psi which sounds about right for the stock turbo. Could there be a boost leak or busted turbo even though the gauge reads 10psi? It really does preform like an NA engine but it holds 10psi on boost and about -18 vaccum at idle. It seems to rev slow under load as well, maybe driveshaft issue? There is a clunk from the rear sometimes when i shift or hit the throttle hard which i believe is my center support bearing but i wasnt under the impression that it would cause a massive power loss like this

The clunk you've described is likely just the centre bearing of the driveshaft. So no, it wouldn't cause a power issue, but yes it should be sorted eventually.

It's strange that you're holding boost, timing is good and AFR's are fine. Quite a conundrum. Maybe you could get a video of the car accelerating for us? Hard to identify further, for me anyway (but I'm no mechanic lol)

Could be your knock sensors playing up and you're falling into the knock maps of the stock ECU...

Get a new ECU or a Nistune, add more boost.

10psi stock RB20DET won't move anywhere.. even more boost you'll still get spanked by a MK5/MK6 VW Golf GTI

  • Like 1

@inmaniac Quite the conundrum indeed ill get a video up soon as i can, it would help alot to get a second opinion on how it revs under load, seem sluggish to me but maybe thats just because its so slow 

@Dose Pipe Sutututu Ima go check those knock sensors i hope its not that though cuz rb parts are hard to come by in the shitty ol UsA lol

@vxsr33 Dyno time is too expensive where im located, and its a DET hence the issue with it feeling slower than a ka24

2 hours ago, Tortise240 said:

 

@Dose Pipe Sutututu Ima go check those knock sensors i hope its not that though cuz rb parts are hard to come by in the shitty ol UsA lol

Nistune it, then highlight the timing map on the knock cells and press 'K'.

@Dose Pipe Sutututu i dont have the time or money for a nistune at the moment but as soon as i can send them my ecu ill get that board installed and tuned. Thanks for the reccomendation i didnt know about nistune before but it looks like the best tuning option by far...cant beat what is essentially a standalone for 500$! Knock sensors looked fine physically but i dont know how to check without nistune

I just ran a compression test and with a cold motor it pulled 125-130 psi in every cylinder. #3 spark plug came out black and was gapped to .6 maybe it wasnt getting enough spark due to improper gap? I double checked the gap for the rest and they were all smaller than .8 but only #3 looked fouled

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