alignment specs

[david c.]

For those of you who autocross your 944's, I'd like to hear what alignment specs you have found to be best.

For reference, the car is an 89 n/a, and it will have stock 86 951 front struts, stock 89 n/a rear shocks/springs, but with the big M030 30mm/19mm Porsche anti-roll bars, 16x7,8 dials, and 225/245 section rubber (but NOT "R" compound rubber).

With the rear bar set for maximum neutrality to counter understeer induced by the tire sizes, I'd like to find an alignment spec that favors the least amount of push. In fact, I wouldn't mind if it bordered just the littlest bit on tail happiness.

Thanks in advance.

[david c.]

I saw this post from an earlier thread. Whaddya think of this for an aggressively driven and autocrossed car:


Autocross is different than track driving and different than daily-driver street use. I recommend the following:

FRONT
1/32-1/16" toe-OUT (for quicker turn-in response)
-3.5 to 5.5 degrees camber (depending upon spring & swaybar rates)
2.0-2.5 degree caster (a little less than stock because you DO NOT need high-speed straight line stability in an autocross)

REAR
1/32-0 toe-IN
-3.0 to 5.0 degree camber (about 0.5 degrees less camber in rear works well)

[nynor]

changing your camber will put you in a different class for PCA autocrossing. if you aren't using R compound tires, this will not help you, as you will be competing against vehicles that are using R compound tires and are inherently faster at autocross.

that said, camber will help you corner faster.

[david c.]

I've been autocrossing various cars for years, but never a 944. I can't run R compound tires on the 944 in the class I want to run with it anyway. So, that's not an option. The 944 is a daily driver, so nothing wild has been or will be done to it's suspension.

I'm just looking for some baseline specs from those who with significant 944 autocross experience, given the above recipe of car and parts. Thanks.

[Techno Duck]

I would be very surprised if a region classed you differently based on alignment as there is no real way to check unless they eyeball it (subjective) or they run around with a Long Acre camber gauge. The MetroNY region and the NNJ (Northern Jersey) dont class differently unless you have suspension work...the NJ club being much stricter..the Metro club allows basically anything with stock mounting points. Also even if you run R-comps you run in stock class.

Check your local region rules of course.

Anyhow, this is the setup i have been running for the last 10k miles or so. Tire wear on my street tires is nothing out of the ordinary. Camber really dosent kill tires, its toe + camber that kills tires. Turn in is great, would love to run a bit more camber to save my tires at auto-x but thats going to kill my street tires. I am looking to get a camber gauge so i can make adjustments myself before each event.

Caster : 3° 18'
Camber : -1°30'
Toe : 0°06' Total : 0°12'

Rear...

Camber : -1°54'
Toe : Left.. 0°09'
Right.. 0°09'
Total.. 0°18'
Thrust angel : 0°01'

The alignment you posted is running alot of camber, if your car is primarly a weekend / auto-x car i guess thats alright...but if its a daily driver i would go a bit more mild.

[Techno Duck]

Also ive been running probably 6 year old completely bald Yokohama A-008P's. For most of this alignment. I corded them back in September. I finally switched to my SP8000 summer tires for the last event and was amazed how much better the car handles with a tire that still has tread on it. I just picked up a set of v710's and am very excited to run those this season.

With the particular alignment above, you will probably wear down the rear insides before the front insides.

[david c.]

Jon,

are you running positive camber in the rear?

David

[Techno Duck]

I think i forgot to put a negative symbol in there. Thats how we loose billion dollar space probes!

[david c.]

A-ha!

I note the post I found with the search function suggests at least a one-half degree difference in the front to rear camber spec (less in rear). Your spec takes a different tack.

I'm also wondering if that makes sense for me, since I'm going to be fighting the larger rear footprint.

[Techno Duck]

When i ran the Yoko's i was running 205 and 225's (stock sizes for 16's). The SP8000's i was running 225/245 16's. The car handled great with that setup for the last event. This season i am going to 225 all around. The wider tires in the front were really nice as i was able to brake just a little harder without locking up the fronts (turbo brakes and no ABS). The same day i corded the Yoko's i flat spotted the fronts really badly.

Its really very subjective what is 'best'. I would talk to the guy who does your alignment assuming he has some experience with 944's. The guy that has a DE prepped 951 and does plenty of 944's.

BTW, even with the offset tire sizes the car handles very well, i noticed with the 225's upfront i was getting much less understeer. The 205's are just way to narrow i think. The car still rotated very well with just a touch of thottle and i learned to trail brake to improve rotation even farther. The 225/245 setup felt the same characteristics of the 205/225 setup, just with less understeer. 205's are probably a better match for a car that weighs 400lbs less.

I also had significantly less tire spin (no LSD) with the 245's. Yes, 147hp can break the tires loose exiting sharper turns! .

[david c.]

Thanks Jon. I'll take your suggestions into the shop when I got. My alignment is off right now anyway since the tow truck that hauled it last week (broken linkage) must have yanked something askew.

[david c.]

Hey guys, if I get my car realigned this week will i throw the new alignment off by replacing rear shocks later this month? Any reason to wait until after replacing the shocks? My alignment is way out of whack from a tow truck and I don't have the new shocks yet anyway so I'm torn.

Thanks -

dave

[nynor]

rear shocks shouldn't affect alignment at all.

[Razorback1980]

Hey Jon,

Only asking because I don't know. When I read the tech note from Porsche on putting the 968 blocks on, it mentioned changing the alignment some...if he doesn't have those blocks should his alignment be different than yours by the amount Porsche suggested?

[david c.]

what are 968 blocks? I am quite unfamiliar with the nuances of the '44 series cars.

[Razorback1980]

Jon and Alex explain it very well here, so read this thread as there is a lot of good info in there. Note that in the Porsche tech bulletin, it recommends changing the alignment specs after adding the 968 caster blocks. I know Jon is running them on his and I was wondering if you were not, then should your alignment be a little different?

17" wheels and M030 suspension

[Techno Duck]

I am pretty sure only the caster settings were recommended to be changed by Porsche with that bulletin. Caster really does not have a huge effect on anything like tire wear, however it does have a noticeable difference in the feel of the car. A larger caster angle will make the steering more stable at speed and not as much wandering. To much and steering effort gets higher. It does have some effect on camber cornering hard.. but i dont think that really applies here.

From reading the bulletin, i think it implies the only reason caster should be set differently is because this tech bulletin is for cars running 17-inch wheels, not because the alignment for cars with 968 caster blocks is different.

One way to confirm this is to compare the stock alignment settings between the 944 Turbo and 968 (can check this in the back of the owners manual). If it does happen to be different because of the caster blocks and you do run 15's still, tell the alignment place to give your car the 968 alignment (which ran 16's stock). Honestly, i would not be to concerned with caster alignment.

[david c.]

I looked around on the parts locator but didn't see a "caster block" listing. Does Pelican sell the updated part?

[Techno Duck]

951.341.023.01

They are available cheaper at other vendors.