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methanol build

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okay let me start this off by saying methanol is still pretty new to me, im used to the old spray and pray but im currently building a 2jz-ge stock bore, wiseco 8.5:1 pistons, slapping a oem 1.3mm gte head gasket in there should bring my compression down to 8.9:1, brangers billet main caps, some kings rod bearings, stock rods arp hardware, crower 272 cam and crower springs, tuning on ms3x 7m cps swap for the distributor, borg warner s300sxe r154 with a spec twin disk clutch, theres a bit about the build but im trying to figure out the ring gap for my build now typically if im building for 30psi of boost wiseco suggests .008" so id be 3.39"x.008"= .027 and some change but my question here is should i bring the compression down for methanol mix? ill be spraying the intake with the methanol or should i stay around that gap size? little stumped on it. thanks in advance

Just to clarify, exclusive use of methanol as a fuel or as a detonation suppressant?

If the former, I'd probably be looking at as much compression as I could get - it's the primary reason for using that fuel.

I'm running it as a mix with my normal fuel which around here I can get between 93 octane and at most 105 octane then my local performance shop offers race fuels which I'd like to keep on hand for track use, I'd say it's a 50/50 use between suppressant and fuel, I've read in a few areas that making the compression changes I'm Making increase detonation risk so I'd like to limit that but I would also like to get power increase safely. I want to run the car as a street strip set up with the maximum amount of power I can reliable maintain.

Woops I didn't realize I asked about bringing comp down I meant should I make the gap in my compression rings smaller run like a .025 or smaller?

I'd recommend leaving the 'tight' gapping to the professional engine builders/racers who can afford to lose the engine while testing/racing. Running a ring a little tighter is something you may get away with but there is no real reason to* and, if the ring ends do butt up, you can expect to lose the entire bottom end of the engine and, if you're really unluck, the head as well - if you're really, really unlucky you could wreck the car and end up in hospital.

*Every back to back test I've ever seen published has shown negligible loss of power/torque, or increase in blowby, until gaps greater than ~40 thou' are used and, even then, there is only a slight variance. Cylinder machining, surface finishing, and 'running in' would be expected to make much more difference.

Ah okay that clarifies some things up for me so I should stay within the ~27 thou' and ill be okay in terms of blow by. I wasn't sure if I was okay going tighter in the aspect of cast iron block but realized that wouldn't have made much sense still. Yes it expands slightly less and yes pistons have thermal coating I'm still certain I shouldn't tighten the gap in relation to that

Depending on the engine - some are notorious for cylinder distortion and resulting blowby - you 'should' be fine, the slightly wider gap isn't going to be an issue according to any liturature I've read on this.

If "reliable" is one of your aims and the gains, if any, are negligible I can't see any reason not to use 27 thou'.

I know these engines can run 800whp stock internals but the "for how long" is an iffy topic it comes down to the tuning as everyone swears on but I think the extra knock protection and slight power adder will help, I'm trying to build the engine to handle more than I plan to run so hopefully between the God awful wiring in the car I'm putting the motor in and what I'm doing with the motor I can make something work

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