Adding 2.02 intake to J heads

gliderider06 said

Question. Would having 2.02 intakes be beneficial to have added the 1.88 J heads on a street car? When I upgrade the cam soon, I was thinking of putting 2.02's in. I have heard that it will not be beneficial if the motor is not seeing a consistent 4000 rpm and also that it will lose bottom end. I also heard that it can add up to 20ish HP across the board. I am upgrading the 360 soon with the Xtreme 268 cam, speed pro flat-tops and 3.91's in the rear. I have less than 1,000 miles on the heads and if it doesn't give significant gains, i'll skip it.
Thanks for your thoughts!

Click to expand...

'The Old Adage > 1.88" vs. 2.02" Intakes

If > the current 1.88" Intakes are sitting low in the Valve-Seat, then an upgrade to 2.02" Intakes is worth 'every penny' of an investment.

But > if the current 1.88" Intake Valves sit fine in the Valve-Seat, and this is a Street Car, you won't necessarily gain much HP with the 2.02" Intakes, unless you're pounding in the 5000 RPM range.

The Comp-Cams XE-268 works great with 'J-Heads' with 1.88" Intakes.

Lift ....................... .477"/.480"
Duration................. 268*/280*
Duration @ .050" .... 224*/230*
Overlap................... 54*
LSA ....................... 110*
Centerline............... 106*

#901 Valve-Springs.... #104 lbs. Valve-Closed ~ #259 lbs. Valve-Open