MY PARTS GUIDE TO MAKING YOUR GT HANDLE & GRIP BETTER !!

MY PARTS GUIDE TO MAKING YOUR GT HANDLE & GRIP BETTER !!

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Gibbo205

Original Poster:

3,572 posts

214 months

Tuesday 1st March 2016
quotequote all
Hi there


Right I promised to right up a review of all the handling modifications I have added to my Mustang GT PP. Let me start by saying I won't be mentioning products such as exhaust, decklids, oil seperators, stripes, steering wheels, gear knobs, LEDs etc. Reason being such products are only changing the aesthetics or the sound of the car, as such a review is not needed to understand their impact. All I will say is the Shelby GT 350 wheel and exhaust are one of the best and most pleasurable upgrades you can make to this car, they totally transform the feel and sound.

So lets get started, I shall use a three tier rating system:
  • HIGHLY RECOMMENDED* - So a must have item, the improvement is fantastic.
  • RECOMMENDED* - Noticable improvement with no/little downsides.
  • NOT RECOMMENDED* - I simply cannot recommend, due to say to much NVH or too little change.
Please bear in mind I fitted each part *ONE AT A TIME* so I could truly discover its effect on the cars handling and dynamics, plus easily pin point any issues that arose.




[size=5]Steeda transmission bracket & bushing insert - $100[/size]




First lets start with the bad, the transmission bushing insert as pictured on the left simply for me created far too much NVH, the resonance/vibration/humm coming through the chassis was too much for me, especially on a road car. YES before anyone ask this was with a 1" hole drilled in the centre. I removed this from the car and my NVH issues were resolved, some might like the race car buzz this part gives, but for me, no thank you!

  • NOT RECOMMENDED*

Now onto the transmission bracket from Steeda, this part adds zero NVH and even though on my car the gear change felt great and I rarely had issues with 2-3rd shifts, this part does make the 2-3 shift easier especially under power on corner exit when changing in the 6000-7000rpm region. As such for so little money and for the fact it offers a slight improvement with no downsides this is staying on the car!

  • RECOMMENDED*




[size=5]Steeda G-Trac brace! - $200[/size]




As our UK/EU cars do not feature a front strut brace the front-end at times can feel a little vague even though turn-in grip is generally fantastic. Adding this part is certainly noticable, not night and day but you can feel its presence and of course a lower brace such as this is more effective than your typical strut tower brace. The car feels more direct and more connected with maybe a hair line wisker more feedback/feel. Overall I like this modification as for me it completely sorts the front-end of the car out, yes its a little expensive and ideally you do need a ramp for installation, but overall a great part from Steeda.

  • RECOMMENDED*




[size=5]BMR Delrin/Spherical Vertical Links - $150[/size]






The stock items are spherical at both ends and do have some deflection. This new part is not only stronger but features a spherical top bearing and a very firm delrin bottom bushing. Installation is relativey easy though lining up the bottom hole for the delrin bushing can be a pain as the delrin bushing has zero play in it. This part is designed to help reduce wheel hop (axle tramp) and by itself in isolation on the car again the results are minimal, it does make a difference but minor again and the ride is a touch firmer, but marginally. So wheel hope is reduced a little and the car seems to have a tad more traction on corner exits. Unfortunately a few weeks after install the bottom delrin bushing started to creak/squeak constantly, that will be our winter weather and salty roads, yes I did use energy suspension lube at installation and generous amounts but in short the delrin bushing has no place on a UK daily driven car. Literally my car sounded like an old banger squeaking/creaking down the road. But BMR stood by their product and agreed to send me new spherical bearings for the lower mount, excellent customer service.

The product is now off the car and stock items are on and can I tell, well it is hard and the car handles and drives fine on stock items with all the rest of my suspension parts added. Will I refit, maybe once I get the spherical bearings but as I won't be drag racing, I might just sell the item with spherical bush.

In short avoid delrin/spherical and delrin/delrin vertical links for this car if daily driven, stick with stock items or go spherical/spherical.


  • Delrin/Spherical: NOT RECOMMENDED* *Spherical/Spherical: RECOMMENDED*





[size=5]Steeda differential bushing insert system - Red: $90[/size]




The differential on stock bushes has generous amounts of play to the point if you launch the car too hard and get wheelspin you can get a lot of wheel hop (axle tramp) and if your aggressive it can feel like the differential is violently bouncing in the car, not a good feel at all. This car stock also has quite a rubberized feeling to the rear like it is over-bushed, no doubt for maximum comfort but Ford went a little to far in my view which gives the rear a feel of being to soft, floaty and bouncy, for example power oversteer can feel floaty though easily catched within reason.

Add these simple parts really do make quite a dramatic difference, it is certainly noticable and even better they are just supporting the stock bushes, meaning they will last longer. This part does reduce wheel hop (axle tramp) for sure and helps eliminate a lot of rear rubberized feeling the car has and also gets rid of some of the floatyness. In short the rear-end feels a lot more direct, more connected and ride comfort is not impacted this part just goes a way in making the car feel more direct/connected, bringing this GT a little closer to sports car dynamics. I noticed barely any added NVH, infact all I could notice and I had to turn the radio off and listen damn hard was a slight humm/whine at 1200rpm when pulling off very slowly in traffic. It is so minor that now I no longer notice it. This part does so much, is easy to install and cost so little.


  • HIGHLY RECOMMENDED*





[size=5]BMR Cradle Lock Out Kit CB005 - $160[/size]

https://www.youtube.com/watch?v=ZeB1RZdlIr0




I really recommend watching the youtube video, it is far easier than trying to explain. This product is simple but hugely effective. In fact this single product from BMR does the function of three seperate Steeda products and cost half the price. In short this product eliminates the rear-end rubberized feeling and floatyness. It also vastly reduces wheel hop (axle tramp) and certainly makes putting power down in all circumstances easier, it tightens the whole car up and really transforms it. It has to be without doubt one of the best modifications for the S550 and is super easy to install. BMR you did a superb job here, congratulations!


  • HIGHLY RECOMMENDED*





[size=5]FRPP Dampers/Shocks, FRPP Toe knuckle bearing & Steeda Ultralite Linear Springs - $850[/size]






So unfortunately as these three parts and the alignment were all done at once I have to talk about the change to the car from all of these items, I cannot pinpoint what part caused what and only assume.

So the dampers, well the GT PP suspension has a major issue of not enough rebound control which causes it to bounce in the rear-end and being rather un-settled over bumpy sections of road at higher speeds which is simply a case of the stock GT PP rear dampers not having enough rebound control. I also believe that when fitted springs with a higher spring rate of more than 10% over stock then one should definetely also upgrade the dampers to more closely match the new spring rates. So even though the upgrades done earlier (listed above) did help reduce rear-end bounce it was still present, it is now completely eliminated after this upgrade.

The springs, I went with Steeda ultralites linear, instead of using the supplied progressive FRPP springs for two reasons, I dislike progressive springs plus they are heavy and I wanted a bigger drop than the FRPP springs provide (1" F / 0.5" R). The ultralite springs are 20% higher spring
rate than the stock GT PP springs, here is a collection of spring rates and drops I compiled:

Front/Rear

GT: 160 / 668
GT PP: 165/728
FRPP Track 5300-Y springs: unknown (1" F / 0.5" R)
BMR Performance: 170/740 (1.2" F / 0.5" R)
BMR Handling: 300/980 (1.2" F / 0.50" R)
BMR Drag: 150/800 (1.2" F / 0.5" R)
Steeda Sport Linear: 198/874 (1" F / 0.95" R)
Steeda Ultralite Linear: 198/874 (1.20" F / 1.05" R)
CJPP: 182-217 / 799 (1.5" F / 1" R)
Eibach Pro Kit: 200-314 / 800-914 (1.1" F / 1.0" R)
Eibach Sportline Kit: 217-331 / 879-994 (1.50" / 1.3" R)
Swift Springs Progressive: 270 / 782 (1.1" F / 1" R)

So the ride quality on the ultralites is superb, at lower speeds the ride is marginally firmer but not to a point where the car is ever uncomfy or to harsh even on some of our UK poorer roads. At higher speeds though the ride quality is improved as the car no longer has any bounce to it as it
just glides effortless over bumps.

Handling is vastly improved, car is flatter, more agile and overall road grip and handling ability is higher and the car looks superb. My only upset is the car dropped more in the rear than I expected giving the false impression of reverse rake due to the wheel arch gap being less in the rear, a look I am not to fond off. I'd far prefer an equal arch gap front and rear or a little more arch gap in rear than front. The car does indeed have rake, as the front is 4.75" off the ground and the rear is over 6" of the ground, so it is impression of reverse rake. I do have a solution for resolving this potentially easily and at low cost, which I shall update with on this reply hopefully this week.

But in short the car looks much better, handles way better and now feels like a true sports car, the levels of grip this car has is staggering, especially considering its running on Pzero's and it handles beautiful with great feedback and progression.

Now back to springs, those who want the perfect stance, so similar drop in the front to mine but less of a drop in the rear to give that rake look and want to maintain stock ride quality then you could simply add BMR Performance springs to the stock dampers, they drop front by 1.1" and rear by 0.5" and are only around 5% firmer than stock GT PP rates.

For those who want same as myself go with ultralite linears or go with the Steeda sport linears as spring rates are same but sport linears sit ever so slightly higher in the rear. If you don't mind a firm car then consider BMR Handling springs but be warned they are firm and do require uprated dampers due to their 300/980 spring rates. These are really a spring for those who have great roads and do a lot of track work who don't want the expense of going coilover setup.

Now for my alignment settings which are for UK roads and tailored to give best handling in wet conditions, as such they are between the stock Ford GT PP recommended settings and Fords recommended settings for the FRPP Kit on track. Ford Recommends:

Ford factory specification is:
Front camber: -1.03
Front total toe: 0.00
Rear camber: -1.50
Rear total toe: +0.23

Ford Racing/Handling specification for circuit / auto X is:
Front camber: -1.55
Front total toe: 0.00
Rear camber: -1.98
Rear total toe: +0.23


As most of you know I've being researching parts for a year and settings so I knew the Ford Racing specification was truly only for track and not ideal for road as a few users had reports using such settings on the road impeded the cars performance, did not improve it.





To translate that into American it reads as following:
Gibbo's recommended settings for UK roads:
Front camber: -1.33
Front total toe: +0.05
Rear camber: -1.55to1.65
Rear total toe: +0.26

So a little more aggressive than the Ford Performance Pack settings from the factory, this will give a great balance of wet handling on roads along with good sporty driving in the dry.

Now onto what the stock suspension adjustments offer:

Toe front and rear, you can dial in easily with stock components.
Rear camber: IT IS ADJUSTABLE, once lowered you can get -1.00 upto -2.50, just undo the upper camber arm bolt, it is slotted, and has a good 2-3 degrees of adjustment available.

Front camber: Camber bolts are an absolute must, there is practically zero adjustment available for front camber, so bolts or top mounts an absolute must. I used BMR camber bolts, they work very well and cost £20.


  • HIGHLY RECOMMENDED* *BMR CAMBER BOLTS: MUST HAVE!!!*





  • VELOSSA BIG MOUTH COLD AIR RAM INDUCTION - $100*






This part is simple, the more cold air you can get to your air box and the lower you can get your IAT's then your car simply has more chance of making peak power more often and won't be pulling timing due to heat soak or higher IAT's.

The part functions as designed, I typically see IAT's staying as close to 2-3c above ambient and IAT's drop more quickly after standing in traffic. So it does its just great and if you were to pair it with a panel filter along with a tune you will no doubt have all the gains of a CAI kit without the heat soaking issues resulting in best quarter mile times and a good 40-50BHP gain which mostly comes from the tune.

The downside is this part is an absolute pain to install especially on a UK car, meaning you have to cut and modify the part and it is very expensive for a piece of plastic. Still this aside the part does the job.


  • RECOMMENDED*





[size=5]Eibach Rear 15mm spacers with longer studs - $150[/size]










You can buy them here:
http://www.ebay.co.uk/itm/Eibach-15mm-Pro-Wheel-Sp...


There are two types of wheel spacer, slip on type with longer studs/bolts which mean your only set of bolts are those bolting the wheel to the hub, this means you can use the Fords recommended torque setting of 148lb/ft which is actually unusually high for a car. This type of spacer is the safest and weighs the least, but seem to be only available upto 15mm, which for the rear in my view is absolutely perfect as it gives perfect stance with absolutely zero poke even on stock alignment settings.

Handling wise well widening the rear track gives the rear more grip, this means the car transitions to understeer more or otherwise known as push due to the additional grip in the rear. To resolve this you will need to add the same spacers to the front or larger. Unfortunately 15mm front spacers still leave quite a lot of recess as ideally you need 23-26mm up front to bring the stock wheels flush with arches with no poke/bulge.


  • HIGHLY RECOMMENDED*






[size=5]Motorsport Tech 23mm front spacers - $100[/size]






Now this is the other type of spacer which bolts to your hub and then your wheel bolts to the spacer, so twice the amount of bolts, so it only takes common sense to realise the risk of failure is increased with this type of design and of course it weighs more. Now thankfully this type of
spacer is common and is very common and thankfully there has being no reported failures and people having being running them for over a year without issue.

This spacer is designed to only take upto 100lb/ft when bolting to the hub and when bolting the wheel up which is quite a distance from Fords 148lb/ft recommendation. As such I installed the spacer to hub at 120lb/ft with blue loctite. I then torqued the wheel to 120lb/ft and a few days later re-checked spacer and wheels, all was tight.

However if you do track days I do not recommend this type of spacer at all, it could be un-safe and of course such a large spacer up front will wear your wheel bearings faster, but again no reported failings of wheel bearings on cars.

The 23mm spacer up front fits absolutely fine with no need to trim the studs, I checked by painting the wheel recesses with paint, torquing up and then removing wheels looking for any prints in the paint and nothing. On the rear though 23mm spacers might require you to shave the rear studs a little, but if you go with my recommendation of 15mm slip on spacers with longer studs you have no worries.

I am investigating some stud options for the front that will allow me to use a 20mm slip on front spacer. If I suceed I shall share this information and part numbers as this would then be track safe.

Contact Lenny at Motorsport-Tech for all your spacer needs, he custom makes them and the quality is superb!

Fitting these front 23mm spacers dialed out the understeer created by fitment of just rear 15mm spacers, car now has a real nice balance and rather insane grip levels in the dry!


  • RECOMMENDED*









[size=5]FRPP Anti-Roll Bars (Swaybars)[/size]


We started at the rear and this was very easy to do, took about 45 minutes:






Rear stock GT PP bar is 22.5mm
Rear FRPP Race bar is 25.2mm installed on softest setting.



Then moved to the front, three bolts are undone from the top and the one under the alternator on the passenger side is undone with spanners from underneath. You then have to wriggle the bar out but it came out easier than expected.






Front GT PP bar is 32mm
Front FRPP bar is 37mm set on softest setting.

The white stuff in the pictures is energy suspension lube, I like to use plenty.


Driving the car with these bars on have certainly eliminated body roll, car is now totally flat and my biggest worry was ride comfort, no fear as the ride comfort is un-changed. smile

So the car is flat, it changes direction better, they have certainly improved the already high grips levels even further and confidence level in the car is now much higher. The car is just so sure footed and the handling balance is spot on, get a little understeer, just add a little more lock and it will took in and the rear stays planted. Now on corner exit one has to try harder to break the rear loose and when it breaks away the car is hugely progressive and controllable, more so than the M3, its a joy. smile

I am rather shocked actually with the corner speeds this car can achieve and the grip it has in winter and on tyres I am not so fond off. Makes one wonder what the car will be truly capable off in warmer weather with wider better tyres.


  • RECOMMENDED TO HIGHLY RECOMMENDED*










[size=6]CONCLUSION[/size]


The car handling wise is now completely sorted, I don't think I could improve it any further on the road, it is totally epic, any further improvements will only come from unsprung mass reductions and better tyres. Unsprung mass could be further reduced with two-piece brake disc, lighter wheels and alu/CF driveshaft.


To summarise here is two stages of recommendation I will make:


[size=5]Stage 1: Looks and handling improvement road[/size]

- Steeda differential bushing insert system - Red: $100
- BMR Cradle Lockout Kit CB005: $200
- BMR Performance Springs: $300
- Eibach 15mm rear spacers: $150
- Motorsport-tech 23mm front spacers: $100
- Alignment setup

TOTAL: $850 + Labour


The above will give you the drop/stance that is absolutely spot on and a nice handling improvement that tightens the car and goes a long way to eliminate wheel hop and reducing rear bounce.


[size=5]Stage 2: Looks & Superb Handling road[/size]

- Steeda differential bushing insert system - Red: $100
- BMR Cradle Lockout Kit CB005: $200
- Steeda Sport/Ultralite Springs: $300
- Eibach 15mm rear spacers: $150
- Motorsport-tech 23mm front spacers: $100
- Alignment setup
- FRPP or Koni Dampers: $600
- Steeda G-Trac front brace: $200
- Anti-roll bars (swaybars) front and rear, 36mm-38mm front and 25-26mm rear with adjustment: $500
- FRPP Toe knuckle bearings: $100

TOTAL: $2250 + Labour


The above will give the car a true sports car feeling and zero rear bounce with great dynamics and will also make it suitable for some light track work as well. Of course you could step it up even more with coilover kits, bump steer kits etc. but for the road I think I have found the best compromise.

Stage 1 is great for looks and offers a nice handling improvement and all way keeping price sub 1k.
Stage 2 gives you the looks but a vast handling improvement that brings the car I'd say to a similar level to a base GT 350 handling wise and well we all know what kind of cars that competes with. smile

My only other big recommendation is a tyre change to Michelin Supersports, the Pzero is frankly poor in the wet and cold conditions, it is OK in the dry but the supersport tyre is better in the dry, vastly superior in the wet and last twice as long.


I hope this helps, hit the thanks button and any questions feel free to ask! smile

mr-white

116 posts

235 months

Tuesday 1st March 2016
quotequote all
I was going to ask you for one of these a few days ago biggrin

Iron Duke

11 posts

109 months

Tuesday 1st March 2016
quotequote all
This is great Gibbo, I had been cutting and pasting your posting into a word document and it wasn't working! I really like what you have done. Keep up the Good Work!

Gibbo205

Original Poster:

3,572 posts

214 months

Wednesday 2nd March 2016
quotequote all
I also previously mentioned about the car having an appearance of reverse rake, due to the arch gap being larger in the front than rear. The fact was the car did have rake as was 4.75" from the ground at front and 6" in rear, but the arch gaps gave the impression of reverse rake. So doing a bit of research it turns out E36/E46 spring pads are of the correct overall diameter and you just need to enlarge the inner diameter to 3.25" for them to fit. I went with 8mm spring pads as the spring is not on the damper, as such there is a leverage ratio, so an 8mm pad gives around a 10-12mm height increase.


[size=5]NO SPRING PADS![/size]





[size=5]8mm SPRING PADS INSTALLED[/size]







I cannot tell you how thrilled I am at the results, the car now has the perfect stance, am absolutely over the moon with the looks and appearance of the car now. smile

So I am still working on locating longer M14 studs for the front so I can use in my view the safer type of spacer on the front.

Then the only visual changes that will happen to the car in the future will be some 19/20" wheels, still can't decide which but I've got a few months to decide. smile