Rb headgasket questions

[mixeds14]

So I'm finally getting around to install all the parts I'm being gathering for the passst few years on my rb (due to life being life) and need some info from y'all guys that had experience on upgrading the goodies on these motors..

Info on my motor.
Stock rb25 neo never being molested
155+ across the board(if I remember correctly)
Ls coils
Freddy intake running stock boost since late 08

Will be running gt30r
75lb injectors
Stealth pump
Power fc with data logit for the neo
Don't know how much boost yet cause that's we're my questions come in.

Is it necessary to change the headgasket and bolts?

Can I get by with the stock headgasket as it is and just change out the head bolts, how much boost could I run?

And if only bolts are require how would I go about changing them without disturbing the headgasket? Any specific order ( by this meaning taking them out in the reverse order one by one or one by one starting with the last bolt that gets torqued if that makes any sense.


Plans for these are autocross purposes maybe some drift from time to time but I dout it

Guys I really appreciate if y'all could help me out, I'm sure this will also help others sometime along the way on how to go about changing out the head bolts.
Thanks again

[xracerx972]

75lb injectors

Where did you find high impedance 787.5cc side feed injectors? Just out of curiosity..

Anyway, I wouldn't change the head bolts or HG if your goals are 500hp or below. Your weakest link (which is well documented) is your ring lands, bottom end hardware and your oil pump crank collar. Being a NEO, you may be lucky and have the revised collar.

I know people that beat the #### out of their internally stock 25's and they just take it. The main thing to ensure is oil pressure and water cooling capability. Plenty of 411 on all of these topics. Hope this helps.

[mixeds14]

75lb injectors

Where did you find high impedance 787.5cc side feed injectors? Just out of curiosity..

Anyway, I wouldn't change the head bolts or HG if your goals are 500hp or below. Your weakest link (which is well documented) is your ring lands, bottom end hardware and your oil pump crank collar. Being a NEO, you may be lucky and have the revised collar.

I know people that beat the #### out of their internally stock 25's and they just take it. The main thing to ensure is oil pressure and water cooling capability. Plenty of 411 on all of these topics. Hope this helps.

They are top feed injectors, neos also come with top feed.
I know there a lot of tread about this but some have mixed answers and not say about the bolts wich is my main concern.

[Darius]

I feel slightly differently. If your goal is 500HP, I think cheap insurance is to replace the head bolts with ARP studs/nuts. That will greatly increase the abuse the stock head gasket can endure and they only cost $150 (202-4301).

Another fastener that RB's are notorious for breaking are the exhaust manifold studs. I'd recommend removing and replacing them even if they aren't broken/seized currently. It is only a matter of time and a boost leak will cause you problems and confusion later on when you're trying to tune. A NEO is quite a bit newer than S1/S2 engines so you will have a better chance of simply removing them with a double nut or even a vice grip. See if you can find some high grade steel studs from McMaster-Carr to save some $$. Their thread size/pitch has been posted if you search.

[mixeds14]

guess bolts will do for insurance. However my question dint get answer on how to go about changing the bolts without distorting the oem head gasket.

Matt, glad u sold the car to someone that's actually Goin to take good care of it and the time/work u put in to it.
Also I will be hitting u up on the fc tune in the next month or so..

[Darius]

guess bolts will do for insurance. However my question dint get answer on how to go about changing the bolts without distorting the oem head gasket.

Matt, glad u sold the car to someone that's actually Goin to take good care of it and the time/work u put in to it.
Also I will be hitting u up on the fc tune in the next month or so..

Oh sorry, that's the easy part. Wait until the engine is cool. Loosen the head bolts from the ends of the block, while alternating, and work your way towards the middle. The ARP studs have a #4 allen key on top and you lightly lube them and lightly tighten them in place. Finish up by installing the ARP nuts in the order shown in the FSM but using ARP's torque specs. I like to tighten them down part way first and then go for 90% torque and then final torque everything, but I'm anal.