Hi guys,

I forget every time i do this, but what length of bolts do you need for a HFC install??

The berk install manual i have states it comes with M10x1.25 bolts, but doesn't give a length......

going off pictures ive seen, im guessing at least 30-40mm long bolts will work?

I have seen people use grade 5 zinc 3/8 diameter SAE hardware too...so maybe 1.5 inch?

I know 10 total nuts and bolts are needed, (if brace is used)
Two studs hanging from the headers (one on each side is M10x1.25)

just need to confirm approx length to buy??

-J

 

This may or may not help but in the Greddy TT Install manual, the 2 studs they provide for down pipe/Cat install are;

M10 x 45mm Stainless Stud P=1.25 – 1.50

But; in there shitty instructions; they also use;

M8 x 15mm Stainless P=1.25
M8 x 25mm Stainless P=1.25

So basically 3 different lengths LOL

Ugh, worst install manual ever.

 

^ thanks, thats very helpful....

it has to be the 45mm length then because M8 is too small to use at the cats...it must be the M10 reference........

that should answer my question...thanks!

I told my bud just to just grab some 3/8 x 1-1/2" long hex bolts and lock washers......
We should be good.

-J

 

The only reason I offered the others is because the kit only included 2 of those M10 studs.

Confusing, I know.

 

^ okay, im guessing it must be #74 then???

at 35mm length...im think im good then..ill verify today when i do the HFC install..


-J

 

Yeah its really a moot point since you have the hardware, and when I built my car I bought all new hardware anyways.

 

I appreciate the help though.......im gonna confirm tonight..

-J

 

Okay guys I confirm that 1.5 inch length is more than enough.......

I failed in that i didnt measure the two flange widths but its a moot point....

So to reiterate:
Dia x length

SAE:
3/8 x 1.5" length work just fine.

or

Metric:
M10 x 35mm

Once again:
For a typical HFC or test pipe install you need 8 nuts and bolts, lockwashers, cut washers, etc as needed.

if your HFC or test pipes have the flange to connect the cross brace then you need 2 more additional nuts and bolts making the total 10 needed. these two can be much shorter than 1.5" length as the cross brace isnt thick at all and usually the flange from the HFC/testpipes isnt either. Just some fyi.

thanks random for your help bud!

-J