Modifications Required to Race an Ultima

[rs_man]

Hi all, I am considering racing an Ultima next season and would be interested in comments from experienced owners about what modification might be beneficial.

[Rusti Evo]

Which series is it you fancy - there don't seem to be many obvious choices for an Ultima

[budala]

rs_man said:

Hi all, I am considering racing an Ultima next season and would be interested in comments from experienced owners about what modification might be beneficial.

Have a look on Grasser Racing website and their shop.
Gottfried Grasser is helpfull too.

[Boosted LS1]

Proper racing or track days? I've a customer who goes to all the big circuits and has done so for three years or so. Spa, Silverstone, Donington etc. He's pretty serious about the car and he'll have done mods to suit. If you want his details let me know, I think he comes here occasionally.

[V8Dom]

went to the Bricar at silverstone at the weekend and there were 2 cars very very simular to the ultima called prosports....... interestingly they had same interior, bins, dash, windscrenn, body but front and rear clip different and front and rear supension was inboard shocks...... worth a look anyway..

one went very very well until he broke down but considering he was low budget team against the high budget teams.... alot of teams were very very supprised.....

Dom

[bluesatin]

I would speak to Master Motorsport who used to run an ultima in British GT series.

http://www.mastermotorsport.co.uk/

[Boosted LS1]

^^ Scuffers runs a Prosport, quite well by all accounts

[Chewy]

I raced my road going Ultima in 2006 successfully in a mid engined sports car series.
I investigated the possibility of racing in 2007 and 2008 in the Britcar series but was not allowed at that time. Times have changed and I see no reason why they would not let the Ultima in Britcars next year – I would expect them to welcome it in the current climate.
I raced with a fairly low spec Chevy engine (311bhp at the wheels) and went for high torque low bhp as it’s bhp that’s measured and torque that gets the car moving.
I found the car easy and a pleasure to drive on the limit even for a beginner like me.
I used a winged race wet sump which worked well but nearly got black flagged due to oil escaping from the dip stick on long right hand bends. I last week got my engine back after fitting a dry sump system which will suit racing better (although the engine showed no sign of wear or failure from using the winged wet sump).
I had a side scoop to help with oil cooling.
I would insist on the rose jointed suspension which uses stronger wishbones and is more tuneable.
I have a Getrag transaxle and needed to replace the cable linkage with a stronger solution after the cables started to seize.
About half hour after a 45 minute race I touched the transaxle and nearly burnt my hand – I have had 2 connectors welded to the box to allow an external oil cooler to be fitted. (After 14,000 road miles and 6 races there were no signs of wear to be concerned about in the transaxle).
I increased the spring rates by 80% but still suffered heavy roll - Anti-roll bars would be advisable. Use the spring helpers as springs became unseated on inside wheel then snapped back in place and unsettled car momentarily.
Well pad the roof roll bar or better still move it towards the passenger side as I struck my helmet on it during a side impact – and I am only 5’8 and was harnessed in very tight.
Leave in the air conditioning as you soon mist up without it and it gets very warm (there was talk a couple of years ago about making it compulsory in GT cars).
Check the regs for the spoiler as I had to remove the second winglet and the main wing could have been much larger.
I would trim the front wings to help tyre clearance.
I had inner half of front split rim wheels changed to increase width to allow wider tyres - that helped with balance. I restricted steering rack as wider tyres would rub on chassis during slow manoeuvring.
I would fit battery boost cables as the small battery can struggle when engine very hot or during freezing mornings before qualifying.

80% stiffer springs and rolling


The Master Motorsport car was a heavily modified sport with a GTR body. Whilst he was very quick he suffered issues with things like gearbox etc. I tried to keep it simple and relatively low spec in the hope of getting reliability whilst keeping costs down.

[k wright]

Chewy,

Would greatly appreciate more details:

spring rates and vendor

how you restricted the steering angle

changes made to the front wheels

Thanks for the post.

[Chewy]

The last set I bought from Demontweeks They were Faulkners I think – went for the cheapest I could find at short notice.
The factory ones are metric 110N/mm rear 80N/mm Front with inside diameter 60mm.
I bought imperial springs and went for 1000 1b/in rear 6501b/in front with inside diameter 2.25in which is 58.5mm.
The slightly smaller inside diameter fit the Intrax shockers better – the standard springs seemed to float quite a bit on the dampers.
I have not used the spring helpers offered by the factory as they were not available at that time but recommend them or something similar but do not know if they accept the smaller diameter springs.

Factory
110 N/mm = 628 1b/in
80 N/mm = 456 1b/in

Springs I fitted were harsh on the road but helped on track (Not quite 80% increase I quoted):-
1000 1b/in = 175 N/mm
650 1b/in = 114 N/mm

The steering rack was restricted simply by sliding a collet over the arm where it extends from the rack. It can’t be seen as it sits under the rubber gaiter.

I got ‘Image wheels’ to split the front rims and bolt on new inner sections which they were able to match but were 1” deeper .

Please do not accept the above figures as gospel because I am going off memory and will not be home until Friday to confirm them

[Chewy]

Forgot to mention 'Dry Brake Refuelling'.
Dependent on the series you enter you may well need dry break refuelling system. The Ultima tanks are not ideal and are too small for endurance racing (40 litres each) - 120 litres allowed in Britcars.
After a 50 minute race both tanks showed empty and the car coughed and spluttered at one point when tanks needed swapping over (despite there being a small link pipe)- very distracting in the heat of a race.

Use the best Brake Fluid - the AP Brakes are great and never a problem on the road but the fluid supplied boiled during the first qualifying session and that was before I really started trying

Edited by Chewy on Tuesday 6th October 22:06

[rs_man]

Thanks for the feedback, much appreciated. I am looking at running in the BARC North West Sports and Saloons : http://www.barc.net/regional_centres/north_west/ch...

Surprised at the spring rates you are running, especially at the front, I currentky race a modified MG ZR and I run a fairly stiff setup with 700lb springs at front (Faulkner also) and that is my heavy end.

My main concern is head clearance with helmet, I am 6ft 1" and might have to look at moving seat over nearer to the centre.

Do you consider dry sump essential, currently running well baffled sump in my race car with no issues. How many stages on the pump is needed and was it difficult plumbing in?

Cheers Tony

[grasser]

in our view, its the most important to have a real good suspention system, what is strong enough for racing.
On the Ultima you have to reweld the pick up points and make some changes on the wishbones to have long fun with the chassis.
The next thing is to have a good brake. Min 360 mm disks. 6pot calipers.
And when there is still more money left, you have to build, like we did in our 2009 Race Ultima, complete different Uprights.
The result is, that the chassis alone was about 9 seks quicker than the original car with same horsepower.

Our 2009 Race car:

http://cdn.images.pistonheads.com/aimg/1370/137007...

was in total more than 15 sek per lap quicker than a good setup Ultima GTR with LS7 Engine and 650 HP!

But this car has alone 85 kg less weight and a full carbon body with flat floor tunnel system and sequential gear box.

[Builder]

Chewy said:

...Use the spring helpers as springs became unseated on inside wheel then snapped back in place and unsettled car momentarily.

Hi Chewy,

This is something I was concerned about in the build process. Looking at the setup, I figured the springs would unseat with the suspension fully extended and I imagined that happening quite frequently when running at the track.

In 4x4 racing, it's not uncommon to see a strap to restrict the suspension travel. What is a "spring helper" for an Ultima?

Thanks,
-- Scott

[V8Dom]

Chewy said:

I got ‘Image wheels’ to split the front rims and bolt on new inner sections which they were able to match but were 1” deeper .

Please do not accept the above figures as gospel because I am going off memory and will not be home until Friday to confirm them

hi Id be interested in this offering by image to replace inner rim for a wider one..

do you remember how much they charged and what options were available as regards to widths.. looking at wider toyo tyres on my car..

thanks dom

[Chewy]

Sorry can't recall the cost but I remember thinking it was quite reasonable.
They can probably do any size you require at reasonable prices.
I prefer the factory supplied OZ wheels as they seem a better finish and the lip on my image wheels turns out which means if I lay them flat it rests on the rim not the tyre and your more likely to kerb them. He may have other designs as it was 5 years ago that I bought them.

[Chewy]

[V8Dom]

hi

its the inners im thinking of widening so curbing wont be a problem, its because im looking at the toyo tyres which are wider so if i widen the front rim, it will pull some of the extra width to the inside and not hit the wheel arches..

ill ring image on tuesday

Dom

[chuntington101]

Builder said:

i Chewy,

This is something I was concerned about in the build process. Looking at the setup, I figured the springs would unseat with the suspension fully extended and I imagined that happening quite frequently when running at the track.

In 4x4 racing, it's not uncommon to see a strap to restrict the suspension travel. What is a "spring helper" for an Ultima?

Thanks,
-- Scott

Scott, i think, and im probably wrong here, that they are effective weak springs that would notmal fully compres with the weight of the car on them. However once the weight is taken off the suspension the effectily lengthen the overall spring. This should help keep the main spring better seated when the suspension is unloaded.

Someone please correct me if im talking cr*p. lol

[Steve_D]

chuntington101 said:

Scott, i think, and im probably wrong here, that they are effective weak springs that would notmal fully compres with the weight of the car on them. However once the weight is taken off the suspension the effectily lengthen the overall spring. This should help keep the main spring better seated when the suspension is unloaded.

Someone please correct me if im talking cr*p. lol

Helper Springs



Steve