Had a very long, disappointing day at IMW yesterday.

Setup
ITR head w/ BC3+ cams
Itr intake manifold
64mm tb
GSR block
rs machine 81.5 itr's
Edelbrock header with 2.5 mod
2.5 exhaust w/ 200 cell cat, magnaflow res and muffler

The only changes made for yesterday were to Marcell's(Mar778c) old proven header and 3" exhaust w/ no cat or resonator and dynomax super turbo muffler.

Dotted line is edelbrock and 2.5 exhaust, solid is marcel header and 3". The plots are two weeks apart from each other but very similar conditions.


The new header has proven to make 10+hp on an identical(same header even) setup previously so we were all a little stunned when we struggled to make the same power as before. We even dropped the rear muffler because we were suspicious of it, but only gained a few wtrq in the midrange.

Im going to run a leak down test on it but I dont think it will reveal anything. This engine just seems like it hits a wall at 175hp.

Anyone have any thoughts or similar experience?

 

I thought Marcell was using a 68mm tb?
What size intake?
Did you run it open header?
Maybe the cat took a dump on you?
It seems odd. Is the head out of your old B16 set-up?

 

I'm assuming d-rob or JK tuned this car, so i won't question the AFR or timing on it.. it does sound like a mechanical issue.

What were the gear settings on those cams.. and although i'm not question Derek or JK, what were the AFR and final timing.

Neptune i assume?

I would see this car making 190+whp EZ..

 

Sorry to hear that he dyno sesh didnt go as planned. How were intake lengths and how did the fuel map look right at that 7kish drop? Pretty erratic to see such a quick drop like that.

 

Tonio,
Yes he was using a 68 and aebs intake but that shouldn't make too much of a difference. Both were run with the same intake, 3" about 18" long with vs and filter. Didn't run it open header but we ran it with just piping to the axle, hardly any change and no difference at top end. No cat on the new setup and same top end off my old b16.

Derek,
Drob tuned it and he tried everything fuel and timing wise. Nothing helped. The only thing we didn't try was cam timing because we ran out of time. Im going to play with the cams myself and run some datalogs. Im running a neptune demon setup.

Mikey,
We were all scratching our heads for sure. I didn't play with intake lengths but I'll take a look at the fuel maps.

Thanks for the responses guys. Im going to check a few things this week. hopefully get some answers.

 

Definately seems rather low for the mods... If looks like the motor is trying as hard as it possibly can to make peak power. It seems to breathe fine, but power just drops... I'm lost.

 

definetely get that figured out man, for them mods definetely not 170whp worthy at all

 

I'm going to go out on a limb and think a little outside of the box.. I had a few cars act kindof weird on neptune, like the dwell ign tables weren't completely compensating like they should...I switched those cars back to crome or whatever else software they had and they seemed to run fine.. they too, also felt like they hit a brick wall, the car revved but just didn't have anymore power..

Have you tried another tuning software?? If the cam gear adjustments dont work and the motor does check out good for leak down and compression, i'd try another software, i've had neptune do this a few times.

 

Maybe you should try the edelbrock vs. Marcels old header both open header.

 

[I've had QUOTE=ALL M0T0R;45223627]I'm going to go out on a limb and think a little outside of the box.. I had a few cars act kindof weird on neptune, like the dwell ign tables weren't completely compensating like they should...I switched those cars back to crome or whatever else software they had and they seemed to run fine.. they too, also felt like they hit a brick wall, the car revved but just didn't have anymore power..

Have you tried another tuning software?? If the cam gear adjustments dont work and the motor does check out good for leak down and compression, i'd try another software, i've had neptune do this a few times.[/QUOTE]

I've had a local tuner tell me something very similar to this,
It was a turbo setup and they changed a few things on there setup and added neptune rtp, and when they brought it back to the dyno it went from around 380whp to 320whp and he couldn't get anymore out of it. But when they put chrome back it the power shot up and went up to like 390whp.
This makes me wonder if I should just go with ectune or a s300 instead of neptune.
So I'm in for results if this is your problem.

 

Post the tables

 

I've had a local tuner tell me something very similar to this,
It was a turbo setup and they changed a few things on there setup and added neptune rtp, and when they brought it back to the dyno it went from around 380whp to 320whp and he couldn't get anymore out of it. But when they put chrome back it the power shot up and went up to like 390whp.
This makes me wonder if I should just go with ectune or a s300 instead of neptune.
So I'm in for results if this is your problem.[/QUOTE]

I know it seems weird.. I like Neptune and Jr is awesome at what he does...but I have had randomly cars act weird on it... Ive had my own share with ectune but nothing like that..

 

ive heard sometimes hondata has a problem from 5-6k, where there is a little hiccup you cant get out. I was tuned on ectune and it works great for how much it cost imo

 

I had a simalar issue where I had pro 1 cams in my all motor b16 and no mater what I did degreeing nothing made power even on crome or ectune so I. Got a set of ctr cams and my whp was much better then of the pro 1s only making 143whp and a 1/4 of 15.6 put ctrs in and was getting 14.1 in the quarter barly tuned

 

That would suggest you were over cammed rather than a tuning system issue and a good example of why bigger isn't always better.

 

I was thinking this as well. If I cant figure it out I may go back and swap them out on the dyno.

Never heard of issues like this but look into it as last resort.

Their dyno reads super low now after they changed a pressure transducer. It used to be a little generous now its the opposite. About 20hp down from before. Stock gsr puts out 135ish on there now.

 

u planning on taking it to the track n seeing what mph u can get out of it?

 

Their dyno reads more like it did when I had version 1 of the header.


It seems like your motor is being throttled. A cam switch is in order but i think we need to understand what is going on. I wonder if we could try one of my old bin files.

 

Yeah possibly but that will just be evidence on my lack of drag experience not really the cars potential lol. Its a heavy 4dr gsr anyway.

 

dam that is pretty low man, i guess only thing to do is take to the track if everything checks out and see how off those numbers are

 

Anything is worth a shot. When we go back I'll ask john to try his hardware/ecu on it.


It justs needs a turbo...lol.

 

do a same-day test with the different headers back to back to determine what the real difference is. If you compare results from some other time with results you get today, you don't know what else is different.

 

Sounds like user error.

 

Here are the original numbers same day testing.



The baseline with the proflow ~181 whp
The final numbers with the proflow ~ 186 whp (minimal tuning)
Initial numbers with the prototype ~ 191 whp
The final numbers with the prototype ~ 197 whp (minimal tuning)

Here's the thread.
https://honda-tech.com/forums/showth...2269504&page=2

 

NepTune gives you access to both the coil dwell times AND the rpm based ignition multiplier.

The coil dwell times at one point were not compensated properly for the expanded RPM scalars and this caused the dwell to be a little low in the upper RPM. This was taken care of well over two years ago.

The same applies to the RPM based ignition multiplier.. if you compare it to the stock table it is a little different, (1-2 degrees off) in the upper RPM range. But it also allows you to edit the values to compensate however you wish in this table OR in the actual timing table.

I have had multiple cars produce the same power via Crome, NepTune, Hondata.. so I am going to say this isn't in the program choice.