Kooks 1 5/8 headers before and after

sur_real1

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Maybe it's in the tune... Maybe the engine is choked with your current modification list... I'd be curious to see the dyno sheets to see just where it loses power.
 

Jumpmaster2015

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Maybe it's in the tune... Maybe the engine is choked with your current modification list... I'd be curious to see the dyno sheets to see just where it loses power.
The new headers would just let my mods breathe better than the factory ones did, its still a night and day difference in tube length. Like I said putting the old tuning file on the car made a huge difference she drives great now, just have no clue where she stands. I am going to try to get on a dynojet now that I have a clean datalog.

I would go back to the same dyno, but I exit the army next week, move back to mn, and they cant squeeze me in.
 

Jumpmaster2015

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Well, ran more data logs and monitored the knock sensors via the x4 this week, and there is still no knock. There is a dynojet tuner in minneapolis that I can use when I get there in a couple weeks. It is not the data I advertised, but at least I can have some bragging numbers finally!

The car is running strong and pulling like hell in the low range. Very happy on the butt dyno end of things!!!
 

Lstruck03

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Any update on this? Ever solve any issues and re-dyno?

Shaun's old thread has me really considering the 1 5/8" kookd mig lengths as well.
 

Jumpmaster2015

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Any update on this? Ever solve any issues and re-dyno?

Shaun's old thread has me really considering the 1 5/8" kookd mig lengths as well.
Your timing is impeccable. I am actually going to the local dynojet tomorrow. I am finally settled in here in Minnesota, and will post the results. I can tell you that she pulls amazing, and I am happy with the car 100%. I would go ahead and buy the headers if my numbers are good. I am also going to the track here in MN soon, so you guys can see those results as well.
 

Lstruck03

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Your timing is impeccable. I am actually going to the local dynojet tomorrow. I am finally settled in here in Minnesota, and will post the results. I can tell you that she pulls amazing, and I am happy with the car 100%. I would go ahead and buy the headers if my numbers are good. I am also going to the track here in MN soon, so you guys can see those results as well.
Awesome. I'm anxious to see the results, and how the power curves show.

I work in a performance shop and 99% of coyotes are either stock header and 3" straight pipe, or 1 7/8" header and full, crazy loud 3" exhaust. I'm not happy with the typical power curve. Very soft down low.

I'm planning a much quieter and nicer sounding setup focused on low/midrange.

Sent from my 2PS64 using the svtperformance.com mobile app
 
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Jumpmaster2015

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Awesome. I'm anxious to see the results, and how the power curves show.

I work in a performance shop and 99% of coyotes are either stock header and 3" straight pipe, or 1 7/8" header and full, crazy loud 3" exhaust. I'm not happy with the typical power curve. Very soft down low.

I'm planning a much quieter and nicer sounding setup focused on low/midrange.

Sent from my 2PS64 using the svtperformance.com mobile app
I am very hopeful that my cobra jet maniold + L&M intake cams + 1 5/8 headers full exhaust + E85 results is a power combo across the board. Maybe everything works together in the high and low/mid range.
 
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Lstruck03

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I am very hopeful that my cobra jet maniold + L&M intake cams + 1 5/8 headers full exhaust + E85 results in a power combo across the board. Maybe everything works together in the high and low/mid range.

I hope it does. I'm planning a very similar setup, only with 2.5" mid pipe and 2 3/4" o/a pipes. The only 3" will be the actual muffler
 

Lstruck03

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Do you have some sort of swap going on? That is not the normal exhaust piping

No swap, but I really want to use the prochamber mid pipe, and it only comes in 2.5" then expands to 2.75 for the o/a pipes.

I think it will be plenty for a stock intake car. I feel like 3" is overkill.
 
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Jumpmaster2015

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No swap, but I really want to use the programme mid pipe, and it only comes in 2.5" then expands to 2.75 for the o/a pipes.

I think it will be plenty for a stock intake car. I feel like 3" is overkill.
Good thinking, that might have an impact on exhaust velocity, which is an advantage of the 1 5/8 headers according to Shaun!
 

Jumpmaster2015

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Well, the good news is that there was never a huge power difference between the two tuning files. We switched tuning files between pulls. That issue must have been a fluke at the mustang dyno. Unfortunately, I am still down a ton of power for the amount of mods I have. I am at a loss. The highest she put out today was 436, and ignore the red pull because that was the dyno operator accidently pulling in 4th gear.

It is plain to see the motor pulls until about 6000, and then stops making power. Those are some fun as hell 6000 RPMs though lol. I need to rethink my car life at this point, not sure where to go from here. The dyno operator recommended we datalog to see if we can uncover some hardware concerns, and once I get a job here that may be logical
Dyno1.jpg
,
 

Jumpmaster2015

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Could it be possible that I have false knock that shows up in the high RPM range on the dyno? I datalogged on the street and couldn't get any to show up...
 

sur_real1

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In my honest opinion, you really seem to be right about where I would expect with your mods. Your cams aren't very aggressive, nor are they a matched set. Your headers are actually small for this motor, and probably your setup. (yes, I know there are lots of opinions about this, but these motors have enormous 4 valve heads that flow tons of air, more than any big block head).

You have amazing, solid mid-range power, which is what you wanted in the beginning of your adventure. To make more power on these motors N/A, you will need to let go of the need for strong mid-range and focus more on the higher range. Which requires more aggressive cam profiles, a larger, quality header, and possibly more fuel or different fuel. There is a thread with a gentleman making about 477+rwhp with a similar setup, but with 1 7/8" headers and Comp Cams stage 3 cams and he spins it to the moon.

Honestly, your setup now kinda lends itself to some boost and that's where I would go if you aren't willing to tear into the engine again. You're motor is strong and looks like it runs really well. Good luck!
 

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^ I agree with that statement. First and foremost, a dyno is a tool. At the end of the day, if they are calibrated correctly, you will get very accurate numbers.

There is a ton of opinionated comments on the boards about how Mustang dynos are the only true dynos, Dynojets and Dynocoms inflate numbers, etc.

I had a similar setup to you, but, with Kooks 1-3/4" headers, stock cams/engine, and laid down 443/388 with knock due to lack of "good" fuel/octane. It's funny as I've seen boss manifold 5.0's on dynojets (I dyno'd on a Dynocom) without headers make 450+ RWHP on a non-ported boss, at that.

AED uses a dynocom which has proven to be very accurate, especially if maintained and calibrated as needed. Numbers on any dyno can be inflated, depends on the operator and their software. Some inflate on purpose to get more business by marketing high numbers, which a lot of people love to see that don't care to track their cars.

Datalogs are a must. Get several. I'd do a normal acceleration log shifting from 1st-4th. Cool the car, then do a harder pull through all gears, followed by cooling the car, then doing a half and a full WOT pull. This is what I did when dialing my car in with Shaun years back. You get a better idea of where the car is lacking and making it's power so you can tweak it at every RPM.

Good luck Jumpmaster.
 

Jumpmaster2015

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In my honest opinion, you really seem to be right about where I would expect with your mods. Your cams aren't very aggressive, nor are they a matched set.
Thanks for everything you said! Yeah the dyno operator said he seemed to think my power is on par with a CJ car with headers and stock cams. It doesn't matter if the cams aren't matched, my exhaust cams are the boss 302s which are practically on par with stock coyote exhaust cams (they don't really add a whole lot, another 2mm lift). I think these numbers prove the exhaust cams are not the baby cobra jets.

Yeah she is fun where she does pulls, It just sucks my up top performance is murdered. I may switch back to the stock intake manifold and sell the CJ if this cant be corrected. Its pointless to have a CJ that cant pull up top.

Good luck Jumpmaster.
Thanks! This aint over. I think I nailed an interview for a business analyst position today, which is what I just graduated school for, so if I get the job I plan on going apeshit with car building.
 

noldevin

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Unfortunately, I am still down a ton of power for the amount of mods I have. I am at a loss. The highest she put out today was 436, and ignore the red pull because that was the dyno operator accidently pulling in 4th gear.

It is plain to see the motor pulls until about 6000, and then stops making power.
A few things:
You mention one pull was in 4th, what gear were the rest in? Should be 5th, lower gears should give lower numbers. Given that the 4th gear pull was the highest, were the rest in 3rd? That could be hurting your numbers.

Second, sur_real and grabber are right. You have pretty conservative cams and have strived to maintain a strong mid range. That typically limits your horsepower numbers but gives you a wider power band (and you have a very fantastically wide and flat power band from 6k straight to almost 8k, that is not a bad thing).

Which brings me to my third point: you don't stop making power at 6k, you level off at 6k and continue to make basically peak power for almost 2k rpm. Your top end is not by any means "murdered", the curve looks exactly how it should, just a bit lower than you hoped.

I'd expect your combo to be making about 460-470rwhp. Either the dyno is reading low, it was in the wrong gear, or you are actually down on power for whatever reason, but the only way to know for sure is go get some trap speeds and see what she does at the track.
 

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