I run a 2006 353 with 496hos and CMI headers but am planning on doing raylar 525 kits in future and was thinking of adding extension boxes. I was told 353 really likes them? Any one have experience with them that could help me decide? I know drives on my boat are little higher that older 353s. Was thinking 12 inch boxes 1 inch up? Will boxes help or hurt prop slip? Will they help carry the bow up?

to retrofit, a lot of $ and work for 2-3 mph.

stock drive height was raised in 2000/2001? If I remember correctly

step bottom boat does not want to run "bow up", They run on the bottom correctly fairly level

99 353 hp500s Stellings boxes and shortys 5 blade hydros won't pull the bow runs dead flat. Don't think u will ever get the bow up on a 353

funny you say that... i had 2 formula 382s 97 and 99 and both pulled the bow and held it .. i now have a 38 top gun twin step pulls the bow
just like the formulas ..you saying thats wrong ???..i know for fact many complaints about 353s riding flat also the formula 312 fastech .i spent alot of time and money on props trying to do so

There was a big difference in attitude from my 311 and my 353 ... Now that I am use to it , no issues ....m

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