As u can see im not running a stock TPI in my sig. As of right now im putting bosch plattinum(not plattinum 4). Anyway since my heads are from the corvette(alluminum)which spark plug is best for my motor. By next month i should get NOS using 150 shot. Anyonw know the torque rating for spark plugs on alluminum head and gap size for the corvette heads on a bored over .30 305 TPI

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92' camaro
New 305 block TPI conversion, Flat top pistons,Bore over .30 Forged parts all around,Edelbrock intake,ported plennum,ported corvette alluminum heads, accel cam,52mm throttle bodie, SLP runners Home aid cold air induction, Air foil,ford SVO 19lb injectors,fuel regulator,cloys timing chain, comp alluminum roller rocker arms and pushrods MSD 8.5 mm wires, bosch plattinum plugs, hypertech cap & rotor and coil, Edelbrock TES headers, free flowing catalytic converter and a 3 inch force II flowmaster exhaust system, and a 3 inch cutout,Zoom multi friction clutch, T-5 tranny,billenstien shocks&struts.
Soon to come!!!
Procharger system 12lbs o boost.
New paint job(hawaiin orchid purple)Cast alluminum ZR1 rims w/ 275 tires.
Favorite quote: "where ever u go, there u are"

Other car;
1971 plymouth Duster
Mods:340,edelbrock victor jr. intake, 650 4 barrel holley, heddman headers,40 series dual flowmasters, cold air intake,4:10 gears, just got a new paint job and cragar rims with 315 tires in the back.
:Yeah its not a chevy but damn how many 71' dusters have u seen in the streets.

 

whatever you decide, tell the parts guy that they are for whatever year vette w/ aluminum heads. when I look up vette plugs from late 80's/early 90's it always specifies iron or aluminum heads. the gap should probably remain the same, unless you have ignition mods such as an msd box etc. that might change tho when running NOS so i'd look into it further. as to which is best, you'll probably find out only by trying a set of each ($$$ ) but if you have good results w/ the bosch, they are pretty good plugs. a lot of people also like NGK's but I myself just run the plane jane AC's. I would use rapid fires, but I dont like any plug w/ the little pad on the tab because losing that in the cylendar wouldnt be good...

 

i see your point thanks+