I'am considering buying a 1999 353 fast-tec with twin 500 efi's how fast will this boat go?? If I added boxes will I see a big difference in speed?

Haulin-A, I had a 2000 353 with 500 efi's (no boxes) and after the props were lab finished I saw 80 on gps. High temp. and humidity would pull it back a couple though! Hope this helps.

I spoke with Formula president Scott Porter at the Miami Show and he that they had better results with the Stellings boxes on the 382 than the 353. Call Fomula directly and speak with one of the tech guys in customer service. They are very informative and know all the numbers.

01 353 no boxes with lab 31s 81.4 gps ARKANSAS SUMMER 90 DEGREES . NELEMS MARINE HAS 3 353 FROM 01 TO 03 BOATTRADER.COM

I believe in 02, not sure about 01 that Formula raised the x-dim. at least on the 353's. They ended up re-forming the silent thunder exhaust with depressions to allow for the drives raising. 2000 s. thunder is straight across on the bottom side. What I was told anyway!

Realize this is an old thread, but wanted to correct the previous comment: I own a 2000 353 and it has the ST box with the indentations over the drives, it is not straight across.

Most 500 EFI 353s should see 80 on GPS. There were two HP500 carb 353s that were 82 and 83 on GPS, one was a firestorm 98 model and the other a 99 I believe. I sold the 98 and another sold the 99 both from Glencove back in 01/02.

I'm thinking my new 353 with 415hp 502's should see 72? It has the factory 4 blade 28's which ive heard mixed reviews on.

This is a 98 btw

I get 76 out of mine and got 30s on it. I hope to see close to 80 with labbed props