Ordered My 1st Cobra - Need Advice Please!!
 

Hi all,

Just ordered my 1st Cobra - a new Superformance MKIII from HillBank, CA. I live in New Zealand, so doing all of this from 6000 miles away is a bit hard not being able to go and talk to the guys at HillBank and see cars 1st hand, although they have been great over email. I have a love affair with the Cobra, but am not a serious garage mechanic!

Main use will be road, with the odd track day with friends for a laugh (nothing serious) - in NZ we have a 100km/h (60mph) limit that is staunchly enforced - I need a setup that will cruise well @ 60-65 mph for highway and obviously be a blast on the on back roads and fun track days.

I'm planning on Roush 427SR and R15s with Avons (295/50 rears). The trick is chosing the trans/diff to give good cruising and spirited driving options.

I may have gone overboard, but here is the current plan - T56 Magnum 6 spd (ratios 2.66, 1.78, 1.3, 1, .8, .63) and 3.73 diff. Tires give 465 revs/km giving following speeds at engine revs:
1st - 6000rpm/48mph - good reach with 1st?
4th - 3000rpm/64mph - in the band for backroads
5th - 3000rpm/80mph - in the band for backroads
6th - 1800rpm/61mph - perfect for cruising with 427SR/TW and having "not-awful" gas consumption?

I could save some real $$ going for TKO 600 and 3.45 stock diff, but the 0.82OD seems too short and 0.64 seems a bit tall in the 60mph range:
0.64OD - 60mph in 5th - 1650rpm - revs seem too low - engine lugging??
0.82OD - 60mph in 5th - 2150rpm - revs higher than necessary for mild cam 427SR??

So the big question is, am I going overboard and wasting money with the T56 and 3.73 diff, or would the 427SR and TKO600 with 0.64OD with stock diff be OK around the 60mph range?

Next question is engine/trans installer. No NZ shops are familiar with Superformance, so I'm keen to get US guys to install enginge/trans and import into NZ as a turnkey. HillBank have put me onto V's Performance in Orange CA as their prefered shop. I've had a couple of good talks to Vlado there - seems like a great guy. Anyone familiar V's?? Recommendations or not??

Miscallaneous stuff:
- V's has recommended ball joint upgrage - thoughts?
- Have seen posts recommending rear shock mount upgrade - is this necessary with new SPF MKIIIs these days?
- Is it worth a front/rear sway bar upgrade for mostly crusing use with a bit of friendly track comp?

Thanks in adviance for the advice.

Steve

Congrats!

'V's" (Vlado) is well versed on the installs and will do a fine job for you.

MY OPINION is that the 6 speed is overkill and the double overdrives are wasted on most "Cobra" applications. The 427SR is not really happy cruising at 1800 RPM and you will experience some surging and bucking at a steady cruise speed at that RPM. Most of our customers go for the TKO600 and the
.82 fifth gear.

Do some searching here at ClubCobra on the choices. As you said, you will save some serious coin with the TKO/3.46 as opposed to the T56/3.73.

If you are going to obey the 100 KMH limit even the TKO .82 is gonna be geared "tall", don't even think about the .64 setup on the TKO.

Hey Steve, MkIV gives sound advice on these things. I have installed a ball joint upgrade and saw/felt a huge improvement. I'm not sure what's up with rear shock mounts these days but look for 4 bolts in place with a spacer/crush collar between so the bolts don't collapse the brackets. Sounds like you've done your homework mate. You'll have a blast with it on the coastal roads. Those Avons are a good call too. Keep your eyes skinned for the "brown paper bags".
Congrats.

These guys are spot on.

Go with the TKO 600. The T-56 is a waste of extra money, space, and weight in my mind, and I'm a distributor for Tremec. Keep the 3.73 gears though. ;)

Oh, and do a search on Roush engines....

Steve I presume you've obtained all the relevant import and compliance approvals from your Transport and Customs departments so that when your new SPF lands on the dock in NZ there won't be any tears..... %/

What you're trying to do would be impossible to accomplish in Australia on so many fronts. Perhaps things are more liberal over there.

Not trying to be a party pooper. Just make sure you've done your homework.

I made the mistake of getting a .64 overdrive with the tko600. So I swapped in the .82
With the 3.46 rear, the .82 is perfect

First of all, do an extensive search on Roush engine problems on this forum and then choose wisely. Read their warranty closely. Does not cover oil usage and getting service means you must pull the engine and ship to them. Find a local engine builder if you can.

If you do go with the 427SR, and IF you have roads where you can safely cruise at 70-75 mph, then the stock 3.46 rear end and the .64 fifth gear will be fine. The SR engine is a torquer and will cruise effortlessly at 2000 rpm and still pull away quickly if more pedal is added. If you are limited to speeds of less than 65-70, then get the .82 fifth gear with the stock rear end.

Since you are so far away, if you want to set the car up properly from the start, have the cobra valley ball joints, adjustable shocks and 450 lb springs, along with their front and rear sway bars installed. They vastly improve the handling and overall feel of the car.

If you look at my specs, I have the same setup you are thinking of, and the engine has been nothing but a headache for me and several others. Mine needed a complete rebuild after 13,000 miles with no help from Roush. If you are set on the name Roush, buy a different engine and I will send you my Roush valve covers and air cleaner. After the rebuild, I replaced anything that had their name on it.

Once again, just my opinion. Enjoy the ride.

Hey thanks for all of the great advice guys!!! Just responding to a view points.....

You've all convinced me TKO600 .82 and save $$

I'm quite lucky in NZ - there are no import restrictions or import taxes (other than the blanket GST of 15%) as NZ doesn't manufacture cars locally. The compliance regs for "scratch built vehicles" as they're classified here are quite liberal. The certifier in my area is a great guy, keen to see the car and help get it through. The biggest hurdle can be noise levels, but get this... he has encouraged me to install a 2mm plate between the head and headers drilled with enough 6mm holes to allow the engine to run... this will guarantee a reading below the 95dBA threshold for his records, he can then pass the car, remove the plates and we can go for a blast - gotta love that!!!!

I've seen lots of posts about Roush issues, and lots who think they're great (there are a few Roushs in NZ that generally get positive raps). Any wise views here?? I guess my logic is they look great, they've sold heaps of 427SRs so they must be sorted by now and the Roush name will help with resale value if I ever decide to sell the MKIII. Or is the reality different??

Biggest Roush drawback for me is that warranty won't apply in NZ, so if there are minor issues, I pay for local shop to fix. If it "falls to bits", I will have to ship back to Roush at my cost for the warranty to apply.

Thanks again guys.......

Hey thanks for that jhv48 - that would be the scenario I fear given being so far away!!! I definitley need to think about a local engine build - will definitely get better support if engine does break!

Also, local build would help pay for sway bar upgrade......

Don't spend the money for a Roush motor, too much mark up for the name on the valve cover. Too many horror stories to risk it from long distance. There are plenty of competent engine builders out there who can supply a great motor. I am also a fan of the TKO600 with the .82 5th.

Ditto. Everything.

A rear end ratio of 3.50 +/- is perfect. No on 3.73's, unless you install the 6-speed, which I wouldn't.

PANAVIA here on CC did install a T56 into his SPF and you can find the thread by searching. I can't seem to find it quickly enough. :mad:

Found it. Here's the thread:

http://www.clubcobra.com/forums/tran...pf-we-did.html

Excellent choice.
You will really like the .82. It is a real gear as opposed to a useless overdrive.

I have the T56 Magnum with those ratios and a 3.54 diff. Yes, it was more money than other options. But, I'd sooner give up the oversized brakes, drysump, ti valves, ti rods, and a bunch of other "upgrades" before I'd give up this trans. It's the only upgrade that I find useful every time I drive the car...

Forgot to mention these things:

The stock sidepipes provided by SPF are extremely restrictive for any engine over about 350 horsepower. Mine had an inside diameter of about 1 3/4 inches. A lot of us have replaced them with aftermarket pipes that had internal diameters of 3 inches. They make a big difference in the breathing and will help your engine (no matter who builds it) develop all the power it was meant to deliver.

Also, quite a few of us with Roush engines quickly replaced the relatively useless vacuum secondary street avenger carb with our choice of double pumper carb. If you do order an engine from Roush, have them install a dp carb instead of the street avenger. They supposedly dyno their engines before they ship them so it should be properly set up for you when you get it. Makes a world of difference in driveability and throttle response.

That's great news Steve. The import regs in Oz are a nightmare to negotiate. Yours sound an uncommonly common sense approach, something unheard of in our strangled bureaucracy. I've never figured out how importing a Cobra, an Individually Constructed Vehicle in Aust, into the country (and let's face it, how many units per year would be brought in?) can be construed as a threat to our mass Commodore and Falcon market.
Good luck with the build, even if it is by remote control. Be guided by the advice you're receiving from the American guys, especially blykins. They've been there, done that. Keep your certifier in the loop and it should be a pain free exercise.
Would you be prepared to post pics/updates of the build over on the Australian site? Many of us would be really keen to see the whole process unfold.

Nice choice of Cobra. So that will be three SPF MK3, 1 SPF GT40 and 1 x Daytona Coupe (Peter Brock Coupe) in New Zealand.
Interesting that you brought directly from Hillbank and not through the Australasian agent as was the previous purchases in NZ. I'm guessing right hand drive, full American spec?

Go the .84, and TKO600.
I like your engine choice for a SPF but think a Keith Craft 482 is a good fit and probably a concensus call on this site.

If you are not purchasing a ADR car (specific for Australia) you will need to have:
Burst proof door latches.
Head restraint (if you are having harness's) you can remove the factory seats and slip in some tomb stones for certification and then change them out.

My SPF handles exceptionally well for a BB car, just dont get of the gas on a apex (slow in hard out).
Traction is no problem and never has been, the foot is a good moderator.
I'm running 17" with Nitto NT01 315x35 and 255x40.

Yeah, I tried to go woth the Aussie dealership, but it has gone out of business - emails bounce and phone rings but never answered??!!

Yep RHD american spec. I wasn't aware of the burst proof latches requirement oops - do you have any more details? I'll go back to Hillbank also. The LVV certifier here gave me the same advice re: headrests so all good there.

I'll post build pics on the Aussie site (still not sure if I'll get V's to build in California or do it locally - need to talk to more local guys)

Am going to talk to Brent and B2Motorsport and Keith Craft about engines.

I assume you live in NZ Nirvhana - can you PM me your number ? - it would be great to have a chat. I had a great talk to Rown Tonkin the other day (do you know Rowan?)

Cheers
Steve

The build is not complex...any good shop/hot rodder/fabricator can do it. Heck call Jac Mac to do it.

I can forward an install manual to review if you like. rick(AT)timemachinesauto.com

No Hardtop?
 

Steve, I have a Hardtop on mine and since you are going to be driving it frequently and cruising a lot, I would urge you to consider one. A bit pricy but, oh so worth it.

Plus my wife just loves riding a Cobra replica that is very protected on long trips weather-wise.

Congrats on your purchase. Product is well made, no, correction, excellently made, you will not regret the purchase. Enjoy.

Juan