Disappointing DynoJet test: GMS coil packs, K&N filters


632C2

GT Owner
Oct 23, 2006
86
Puyallup, WA
I have been anxious to test the Granatelli Motor Sports 4V coil pack system since Tony @ HP Performance first told me about them a month or so ago.

On paper and on their website video they looked real good. Unfortunately for me, the results were mediocre. I have displayed 8 runs on this graph to give you an idea.

gt_6.jpg


RUNFIL~3.DRF: Stock coils. TR7-IX plugs @ .030". The Max Power on this run should be 771.70 and not 782.07. The 782.07 was a spike at the end of the run and not valid.

RUNFIL~5.DRF: GMS coils. TR7-IX plugs @ .030". First run with GMS coils. Lost a little power.

RUNFIL~6.DRF: GMS coils. TR7-IX plugs @ .035". According to the instructions, they recommended experimenting with increasing the plug gap by .005" to .010". It didn't sound good above 6200 rpm.

RUNFIL~7.DRF: GMS coils. TR7-IX plugs @ .030". Besides closing down the plug gap, I leaned out the A/F a little and the results were good. This time it sounded good above 6200 rpm.

RUNFIL~8.DRF: GMS coils. TR7-IX plugs @ .030". A duplicate of the prior run.

RUNFIL~9.DRF: GMS coils. TR6 plugs @ .028". Just for kicks and grins, I put in the plugs from my previous dyno session. Basically no change.

RUNFI~12.DRF: Next day. Stock coils. TR7-IX plugs @ .030". I wanted to check the stock coils again. There was a small increase in power over the last run from the previous day.

The conditions were a little bit different on this day as compared to the previous day. On the previous day, the ABP=29.8 / Temp=55.2* / Humidity=51%. On this day, the ABP=29.5 / Temp=52.8* / Humidity=49%. On the previous day the SAE correction factor was 96.2% and on this day it was 97%.

When I was removing the GMS coils from the car, the ear on one of the coils cracked and broke loose. The attachment of the coil to the "rope" and the "rope" to the spark plug is much more positive with this system and requires some effort to detach the coil assembly from the spark plug. Now I see why the stock ones are so easy to remove.

The bottom line is very little to no difference when running the GMS coil packs. Like I said, disappointing. A lot of work for no payback. Oh well, this it was testing is all about. At least I didn't lose any significant power like the next run.

RUN_FI~13.DRF: Stock coils. TR7-IX plugs @ .030". K&N filters. This run was actually worse than it looks. As soon as I put on the filters, the car ran like crap. It was hunting up and down at an idle and almost died. It was struggling to maintain an A/F of 14.7 in closed loop. When shifting gears, the motor wanted to die when I let off. The A/F during the run was very rich. These filters are very restrictive when compared to the stock ones. Looking at them, you can see that they have less sq.inches of filtering material. Once again, the results speak for themselves. I made one more run with the factory filters and the numbers were back up where they belong and the idle was smooth and clean.

Well, there you have it. In terms of finding more power, this was a waste of two days. That is all the dyno testing for me for now. I am quite satisfied with the overall results of the Whipple install and I can't stand having to wait before I am able to drive the car. When the weather finally does clear up (springtime) I will be heading out to the drag strip to see how many runs I can get in before they kick me out.:biggrin

Steve
 

B O N Y

MODERATOR & FGT OWNER
Mark IV Lifetime
Sep 5, 2005
12,110
Fresno, Ca.
I have been anxious to test the Granatelli Motor Sports 4V coil pack system since Tony @ HP Performance first told me about them a month or so ago.

On paper and on their website video they looked real good. Unfortunately for me, the results were mediocre. I have displayed 8 runs on this graph to give you an idea.

gt_6.jpg


RUNFIL~3.DRF: Stock coils. TR7-IX plugs @ .030". The Max Power on this run should be 771.70 and not 782.07. The 782.07 was a spike at the end of the run and not valid.

RUNFIL~5.DRF: GMS coils. TR7-IX plugs @ .030". First run with GMS coils. Lost a little power.

RUNFIL~6.DRF: GMS coils. TR7-IX plugs @ .035". According to the instructions, they recommended experimenting with increasing the plug gap by .005" to .010". It didn't sound good above 6200 rpm.

RUNFIL~7.DRF: GMS coils. TR7-IX plugs @ .030". Besides closing down the plug gap, I leaned out the A/F a little and the results were good. This time it sounded good above 6200 rpm.

RUNFIL~8.DRF: GMS coils. TR7-IX plugs @ .030". A duplicate of the prior run.

RUNFIL~9.DRF: GMS coils. TR6 plugs @ .028". Just for kicks and grins, I put in the plugs from my previous dyno session. Basically no change.

RUNFI~12.DRF: Next day. Stock coils. TR7-IX plugs @ .030". I wanted to check the stock coils again. There was a small increase in power over the last run from the previous day.

The conditions were a little bit different on this day as compared to the previous day. On the previous day, the ABP=29.8 / Temp=55.2* / Humidity=51%. On this day, the ABP=29.5 / Temp=52.8* / Humidity=49%. On the previous day the SAE correction factor was 96.2% and on this day it was 97%.

When I was removing the GMS coils from the car, the ear on one of the coils cracked and broke loose. The attachment of the coil to the "rope" and the "rope" to the spark plug is much more positive with this system and requires some effort to detach the coil assembly from the spark plug. Now I see why the stock ones are so easy to remove.

The bottom line is very little to no difference when running the GMS coil packs. Like I said, disappointing. A lot of work for no payback. Oh well, this it was testing is all about. At least I didn't lose any significant power like the next run.

RUN_FI~13.DRF: Stock coils. TR7-IX plugs @ .030". K&N filters. This run was actually worse than it looks. As soon as I put on the filters, the car ran like crap. It was hunting up and down at an idle and almost died. It was struggling to maintain an A/F of 14.7 in closed loop. When shifting gears, the motor wanted to die when I let off. The A/F during the run was very rich. These filters are very restrictive when compared to the stock ones. Looking at them, you can see that they have less sq.inches of filtering material. Once again, the results speak for themselves. I made one more run with the factory filters and the numbers were back up where they belong and the idle was smooth and clean.

Well, there you have it. In terms of finding more power, this was a waste of two days. That is all the dyno testing for me for now. I am quite satisfied with the overall results of the Whipple install and I can't stand having to wait before I am able to drive the car. When the weather finally does clear up (springtime) I will be heading out to the drag strip to see how many runs I can get in before they kick me out.:biggrin

Steve


Interesting trial, thanks Steve. I am very anxious to see what you do on the strip, I am guessing trap speed of 145mph+:banana
 

todd

GT Owner
Feb 3, 2006
1,020
so. ca.
thanks for the info. I had heard before that K&N filters were not as good as claimed.
 
Aug 25, 2006
4,436
Your effort is well recognized and very much appreciated; the fact that you were so diligent in your efforts and then shared the results will certainly help many when it comes time to make critical decissions; thank you

As for the K&N filters I too stayed away from them however largely because of MAF associated issues in the past. Furthermore the OEM paper are huge and I see no restriction with them and also no associated MAF risk and yet I know that many folks love them. Opinions vary on these so I only share my direction not the direction that others should take.

All the best

Shadowman
 
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632C2

GT Owner
Oct 23, 2006
86
Puyallup, WA
Interesting trial, thanks Steve. I am very anxious to see what you do on the strip, I am guessing trap speed of 145mph+:banana
My pleasure. I would be ecstatic if the car runs anywhere near 145 in the quarter. The problem will be in making a perfect run right off the bat since anything quicker than 11.99 will require a roll bar. My experience is that tracks up here have a zero tolerance policy on the 11.99 rule.

todd said:
thanks for the info. I had heard before that K&N filters were not as good as claimed.
You bet! I have been a user of K&N since I can remember and have always had good luck with them. This one really shocks me.

Shadowman said:
Your effort is well recognized and very much appreciated; the fact that you were so diligent in your efforts and then shared the results will certainly help many when it comes time to make critical decissions; thank you

As for the K&N filters I too stayed away from them however largely because of MAF associated issues in the past. Furthermore the OEM paper are huge and I see no restriction with them and also no associated MAF risk and yet I know that many folks love them. Opinions vary on these so I only share my direction not the direction that others should take.

All the best

Shadowman
You are welcome and it's my pleasure. I agree with you completely on the filter issue.

Steve
 

50 BMG

Well-known member
Aug 3, 2005
559
AZ
Do yourself a favor and go back to stock or try weapon X

IgnitionCoilInterconnects.jpg
 
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632C2

GT Owner
Oct 23, 2006
86
Puyallup, WA
Thanks for the info. I have been monitoring those threads since they were posted and decided to go with the GMS based on availability and Tony's recommendation.

I have no regrets about giving the GMS units a try but I am going to let someone else try the WeaponX units.

Based on my tests, either the stock units are doing as good a job as can be done or the GMS units are no better than stock. According to the video on their website, these GMS units should have produced far better results.

I would hate to go through the time and expense of buying a set of WeaponX units and then testing them only to find similar results to what I found with the GMS units. I can live with having one set of coils laying around but not two.

Steve
 

50 BMG

Well-known member
Aug 3, 2005
559
AZ
More than understandable.

We'll be testing the Weapon X units but not on a GT.

Thanks for the data...
 

Bart Carter

GT Owner
Mar 12, 2006
272
Las Vegas
The only time a different coil is going to be able to provide more power is if the current coil is not doing its job.
 

50 BMG

Well-known member
Aug 3, 2005
559
AZ
The only time a different coil is going to be able to provide more power is if the current coil is not doing its job.

Yep.

These different COP's were initially designed for the 4.6 2V & 4V...the stock COP's have been documented on dozens of cases to fail/peter out in higher HP applications.

Of course more data is needed, but unless your stock GT COP's are failing...party on with what you got :banana
 

BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
Thanks for the excellent write up and testing. Has anyone tried the Kenny Bell Boost a spark? I know only what I have read on the web site. I seems to increase the primary voltage to the coils during high boost situations. If the car's electronics can handle the high voltage then in theory one would get a higher spark voltage too and thus be able to gap the plugs a little wider.

Will that translate into more power? Who knows until the an experiment is done like this one.

It seems that the stock system works fine with higher boost if you gap them down to 0.030 vs. the 0.035 stock.

BlackICE
 

QKSTNG514

Well-known member
Mar 8, 2006
110
Orange Park FL
I see Steve has been busy!!

Bare with me I have been sick for a week.

We did some of the original testing on GMS coils using a an 01 Bullitt that we have been running for several years and using the ABA test we did see gains with them..Not much but 9HP was a lot with just a coil change..

I have installed them and not seen any gains on some vehicles.. Joe's has had the lower parts installed since we were at the 718HP level..

I will say that if you use the stock coils then use the GMS lower connectors since they DO transfer voltage MUCH better than the stock "Slinky" wires.

I have not seen he X's used yet but they do show promise.

I have talked to company that makes these for GMS and they are very forthcoming on info concerning them. I will pass this to them tomorrow and see what they say about the results.

Torrie showed no gains on his either but we had changed the plugs from what he had at the PRI show and I am curious as to what it would have done with the 7's in it.

Steve, I think we need to check the Tornadoes on the GT next!!!!! LOL

TonY G
 

tmcphail

GT Owner/Vendor
Mark IV Lifetime
Apr 24, 2006
4,102
St Augustine, Florida
I have been sitting here analyzing multiple dyno runs on my own car with the stock coils and the GMS units trying to see if I can visually see any positive or negative gain. I can't come to any sort of positive conclusion. The stock coils are back in my car now along with C16.
 

632C2

GT Owner
Oct 23, 2006
86
Puyallup, WA
Thanks for the excellent write up and testing. Has anyone tried the Kenny Bell Boost a spark? I know only what I have read on the web site. I seems to increase the primary voltage to the coils during high boost situations. If the car's electronics can handle the high voltage then in theory one would get a higher spark voltage too and thus be able to gap the plugs a little wider.

Will that translate into more power? Who knows until the an experiment is done like this one.

It seems that the stock system works fine with higher boost if you gap them down to 0.030 vs. the 0.035 stock.

BlackICE
Now that would be an interesting test. But like I said, someone else will have to do it. Now if there are some measureable documentable gains with either the Boost-a-Spark or the WeaponX, I'm there.


QKSTNG514 said:
I see Steve has been busy!!

Bare with me I have been sick for a week.

We did some of the original testing on GMS coils using a an 01 Bullitt that we have been running for several years and using the ABA test we did see gains with them..Not much but 9HP was a lot with just a coil change..

I have installed them and not seen any gains on some vehicles.. Joe's has had the lower parts installed since we were at the 718HP level..

I will say that if you use the stock coils then use the GMS lower connectors since they DO transfer voltage MUCH better than the stock "Slinky" wires.

I have not seen he X's used yet but they do show promise.

I have talked to company that makes these for GMS and they are very forthcoming on info concerning them. I will pass this to them tomorrow and see what they say about the results.

Torrie showed no gains on his either but we had changed the plugs from what he had at the PRI show and I am curious as to what it would have done with the 7's in it.

Steve, I think we need to check the Tornadoes on the GT next!!!!! LOL

TonY G
Hope you are feeling better. You sounded terrible on the phone. This has been a learning experience for me. No one twisted my arm. Their website is quite convincing. You have finally caught on to me with the statement about the Tornado!!:frown

BTW, what should I do about the coil with the cracked ear?


tmcphail said:
I have been sitting here analyzing multiple dyno runs on my own car with the stock coils and the GMS units trying to see if I can visually see any positive or negative gain. I can't come to any sort of positive conclusion. The stock coils are back in my car now along with C16.
Where were you when I needed you?:biggrin Seriously though, I need to follow your lead on this one. If you find something that works for you mega-horsepower beast, I'll get it for my deal as well.

I just need to show a little patience.

Steve
 

QKSTNG514

Well-known member
Mar 8, 2006
110
Orange Park FL
Call GMS tomorrow (May have to wait till next week) and get an RMA number.. Renee is a good guy to talk to there although you may not be able to get ahold of him since JR keeps him busy!!!


If you need me to intervene drop me a note and I will give them a call for me.. Take a few pics of the COP and send it to me and I will forward it to them if needed.

The Tornado was Joe's idea when we were building the original TT setup..

Tony G
 

ByeEnzo

GT
Mark IV Lifetime
Le Mans 2010 Supporter
Dec 10, 2005
2,283
Fort Worth, TX
Your effort is well recognized and very much appreciated; the fact that you were so diligent in your efforts and then shared the results will certainly help many when it comes time to make critical decissions; thank you

As for the K&N filters I too stayed away from them however largely because of MAF associated issues in the past. Furthermore the OEM paper are huge and I see no restriction with them and also no associated MAF risk and yet I know that many folks love them. Opinions vary on these so I only share my direction not the direction that others should take.

All the best

Shadowman

I went out for a spirited road run on Xmas day. Whenever I pulled up to a stop the car was idling really irratic. When I had my Ida pipes installed, I also changed over to K&N filters and vent blockers (Ida's cold air kit). When I got home I changed back to the stock filters and also cleaned the MAF sensor with alcohol. The car now idles normally after getting up to running temp. Makes me wonder if the K&N filters were restictive, or gumming up the MAF sensor.
 

STORMCAT

GT
Mark IV Lifetime
Le Mans 2010 Supporter
May 25, 2006
7,551
Ft. Lauderdale
Anybody want a good deal on a new set of GMS coils and connectors??:ack . If you do find any gains let us know the hot set up or I'll just leave them in the box...I guess I was hooked by their video!!
 

Accufab

Well-known member
Mar 14, 2006
142
In certain instances, these type coils will help when the spark is blowing out due to boost. That's not what is happening on the GT's. It appears to me that most on this site are either being mislead or assuming that the spark is blowing out based on dyno curves. What is actually happening is a valvetrain control issue (lack of control). It cannot be cured with plug gap, coils or any other tuning or spark amplifiers. If the valve isn't closed on time nothing else matters and tuning can make it a little better but that's all.

The only cure is to change the cams or get used to the problem. I will be conducting engine dyno testing in the upcoming weeks for a Muscle Mustangs story that will cover the details of this as well as new cams, testing a prototype Kenne Bell blower as well as the Whipple 3.3. I will post the information as soon as we are done testing.

John Mihovetz
Accufab Inc
 
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50 BMG

Well-known member
Aug 3, 2005
559
AZ
The only cure is to change the cams or get used to the problem...

I've been referring to your cam tech on MF (that long cam thread you started)...

If you wouldn't mind, when it's all said and done, could you share your cam specs please?
 

QKSTNG514

Well-known member
Mar 8, 2006
110
Orange Park FL
John,

Looking forward to the info on the cams/valvetrain situation. We have found several things that need more investigation on the GT's and I would like to discuss some of them with you sometime..

TonY G