Rx7_Nut13B

iTrader: (1)

When i do my build on my FD i want to replace the main bolts with studs

So far i have found two companies that supply these stud kits, both look about the same, except the Mazdatrixs ones have better bolts i think.

Just wanted some feedback, If anyone has used them, Worth the extra money, Witch one is better.

I really think these prices are a little high for what you are getting!!!

WWW. Turblown.net

13B stud kit

-Aircraft quality forged steel
-Hot rolled threads
-195000 psi tensil strength
-No maching is required
-Works with OEM or aftermarket flywheels
-All necessary harware included
-Replaces all 16 inner tension bolts

-More accurate tensioning of engine
-Studs will not yield(stretch) like the factory bolts, which act like bubble gum - high boost engine expansion reduced
-Factory bolts twist while torquing and eventually untwist overtime
-No friction at threads from twisting, not just reducing wear of threads, but friction gives inaccurate torque readings

-Less chance of bolt breakage from vibration or high rpms
-Superior quality material

$350 shipped


And

http://www.mazdatrix.com/studkit.htm

Stock Diameter Kit

Studs are less prone to stretching under high boost applications. More accurate tensioning of engine. Less chance of bolt breakage. High quality 12-point nuts rated at 180,000 PSI tensile strength. Studs manufactured from 4140 chrome moly, heat treated, centreless ground and black oxided. Note the standard factory manual flywheel cannot be used with the Stud Kit.

$406.80 + Shipping

Turblown

iTrader: (12)

Our studs are now coming with the allen head cast into the head of each stud for easier installation. The material out studs are made out of is very expensive. Having a stud with a poor quality material isn't going to do much besides offering more precise torquing. The better the material the more you increase clamping pressure.

Mahjik

iTrader: (1)

I'm using the ones from Xtreme Rotaries in Australia. At the time I bought mine, no one in the USA carried them (or at least they weren't advertising them where I could find them). Either Mazdatrix is selling the same ones or they are just reusing their pictures.

Here's a shot after installation:

http://mahjik.homestead.com/files/FD...7/DSCF0448.jpg

ErnieT

iTrader: (2)

Guru Motorsports were the first company to come out with the stud kit. Most others have coped in suit. The biggest thing is, YOU MUST have a fantastic machine shop to the drilling and tapping. It MUST be perfect, otherwise the purpose of the stud kit is defeated. Trust me, I know, I found out the hard way. I have the stud kit, but maching was a bit off and it had to be enlarged to fit all the studs, but at this point it looses its purpose of a dowel. I also have the Guru e-shaft which is a fantastic addition. The thing is you guys don't need this stuff unless your racing or running very high boost (30Psi and up).

Rx7_Nut13B

iTrader: (1)

The kits i am looking at does not req. you to drill and tap anything, they are the same size as the stock ones ( At least where they enter the iron at )

Mahjik

iTrader: (1)

The kit on my car is the kit which is larger than stock but does not require machining.

ErnieT

iTrader: (2)

How can it be larger but not require drilling? You have a link, by chance?
Thanks.

Turblown

iTrader: (12)

1mm larger diameter

Mahjik

iTrader: (1)

Its on the Xtreme Rotaries site (which are selling the Guru products). The stock bolts are just under 10mm and the studs are a little over 10mm. Sorry, I don't have the email from them anymore with the exact measurements but it was a little under 1mm difference.

Rx7_Nut13B

iTrader: (1)

Well i used the search and didnt find anything on these on the fourm, so i posted this..


MAN, I HIT A GOLD MINE OF INFO.




I think you are right the kit from Turblown and Mazdatrix both are just a little bigger but doesnt req drilling.

ErnieT

iTrader: (2)

Thats cool. I bought my e-shaft and oversized bolt kit from them. I'll get my next bolt kit, stock sized, like you did. Save me a boat load of headaches that way. I shouldn't need it anyway using the e-shaft.
Thanks again.

TrboRty

iTrader: (1)

Notice with those kits you can't use the factory flywheel..uh what other options do you have? Because I like the acceleration with a stock flywheel that I get.

hondahater

iTrader: (2)

I think there is one...maybe turblown? Not sure but it does let you retain the stock flywheel. I was thinking about getting this stud kit as maybe not only is it a little bigger but also isn't the material used for these studs alot harder than the stock tension bolts?

Turblown

iTrader: (12)

Just needs to be mentioned with the order, and ours will fit with the oem fc3s flywheel.

BDC

No reason to change to studs, guys. Stay with the factory tension bolts.

B

Blake

Not entirely true. We were doing oversized studs around the same time as Rohan or perhaps a bit earlier, but no one knew it because my business parter Rob is the biggest Secret Squirel in the universe and kept it underwraps (like almost all the cool stuff we do). We didn't know anyone else was doing it until Rohan showed up at Sevenstock with a display several years back. The difference in approach was intereting, however. Rohan's stuff was all custom while we "borrowed" a stud from a 6000hp Top Fuel dragster head, manufactured by ARP. Amazing what you find in catalogs! Rohan also replaced *all* the bolts while we only did the critical ones around the dowel and combustion areas.

Anyway, we hardly ever find applications requiring these massive studs, since you can make 700rwhp or more (with proper tuning, of course) before you start to see a need to reinforce the dowels on a 13B-REW.

Mahjik

iTrader: (1)

I've seen/read a lot of road race cars recommending dowel pinning (one's running a lot less than 700 HP). I believe all the PP engines Daryl Drummond builds for GT3 RX7's (if he's still building them) are pinned. In which case, these studs would be a good alternative for those road racing RX7's who don't want to deal with the added cost of pinning.

IMO, any car application being put in extreme usage (i.e. high powered drag racers or road race cars under constant high rpms) would be the ideal candidates this type of modification. I believe Pettit Racing was also looking to use them in their race engines although I don't know if they ever did.

banzaitoyota

I only wish some shops paid MORE ATTENTION to detail during assembly; than playing "secret squirrel"