I should be receiving my 4-2-1 header today - woohoo!

Would someone tell me what the metric bolt size is for the flange/head connection? (for example: M5 x 1.25 x 20mm or something like that.)

If I read the "how-to's" correctly, there are three bolts and two nuts holding the header flange to the head. Once I have my car apart, I don't want to reassemble it and drive to my hardware store just to buy new bolts. And, reading Mikochu's write-up concerns me that the stock bolts may be too weak or too short. Since I have an '06, Toyota may have put in the "new" shorter bolts which apparently don't work with aftermarket headers. The bottom line is that I'd like to pick up these bolts BEFORE I have a problem bolting the new header engine.

Thanks in advance for your input.

- Al

 

If you spray the bolts down with some PB Blaster or WD-40 like Mikochu said, it wont take a ton of force to get those bolts and nuts off, this will help so as not to strip the heads on them. I have an 06, and i did not have a problem with a single bolt or nut striping. Just make sure you get some good leverage on them and they will break free just fine. Good luck

 

Thanks, Proshop.

So, the bolts on an '06 are long enough for the thicker aftermarket header flanges?

 

Yup they should be fine and i put the same header on. The biggest problem like we told you in the other thread is getting the the two spring loaded bolts off( tons of muscle needed or air tools works). The best advice i can give you is just becareful, if you think your gonna strip the bolt, due to a bad angle on it or anything else stop and rethink if there is a better way to do it or reposistion yourself.