ARP Head studs and Head Gaskets

[adamdix]

Hi

Im looking to reduce the amount of detonation from my sr20. Its running 340bhp at 1.35 bar on a gt2860rs (spiking upto 60-70 on my pfc commander on a 4/5th gear pull)

Im looking at getting arp head studs and a thicker head gasket, Where are decent places to buy these from (probably a full head gasket set tbh)?
I'm not sure about trusting eBay some of the time.

Also I've got new bkr7 iridiums and when apt mapped it for me we set the plug gap but for the life of me I can't remember what it was.

Finally I've thought about water meth injection too, it doesn't seem to have many down sides and with the sr being prone to knocking I'm wondering why I've rarely seen it used?

Cheers

[ANDY black s13]

Imo if APT mapped it speak to them first,as could be a timing issue they can tweak correct or something else they can deal with
the ARP's are good for further power gains,and a thicker HG will lower CR a smidge,but that alone won't really fix a det issue

[zeppelin101]

You need the map tweaking primarily, I wouldn't be seeking a hardware solution.

Finally I've thought about water meth injection too, it doesn't seem to have many down sides and with the sr being prone to knocking I'm wondering why I've rarely seen it used?

Cheers

Getting it to work properly can be tricky. Ideally you would need to inject the water directly into the cylinder at high pressure to get the maximum benefit, the further away the water is injected the more surface wetting there is which causes the efficiency to drop quite significantly. If you're mixing with fuel then you have more margin for error but methanol is really horrible stuff, I wouldn't use it out of choice. It's highly corrosive and doesn't burn with a visible flame.

All of the aftermarket kits are essentially just a switched valve as well, which means that you'll spend a lot of time injecting water at a closed valve which causes problems with fuel preparation during injection. This reduces the benefit some more as well.

It can work really well, but getting it there needs some careful thought as to how you're going to install everything.