10' GW Invader Help

[Malidrag]

Well I got a prop for a whole 32 bucks off of craigslist to start. It is a stock 11-3/4 x 17p. Threw the boat in and hammered down.. Got a good constant 45-47mph at wot. Not sure on rpms at the moment but wasnt planning on this prop to work as it did either..

I noticed 2 main things. the boat from when it gets on plan to about 30mph porposes a bit.. At 40mph the nose drops and plants down and shes ready to rock. Then the second thing at WOT happens. Feels like the ass end is slighlty shifting left to right like ur fishtailing in away but not to a large extreme.. Is there anything I should be doing or can do to correct these things? I love the spped and at the moment the bow is still running wet. I didnt re pin the motor and retry try cause I ran out of time.

I have ordered a prop that was suggested to me and hope it will help. Its a 12-1/2" x 21p cleaver prop 3 blade.

Any help would be apreciated.. Thanks

[Ineedadoctor2011]

go with a mark 55! its weighs nothing, and you will get mid 50's for sure

[flavio mendez]

I recently bought an 11 1/2 foot Invader style boat. I have a 40hp Mariner, 2 cylinders and about 150 pounds. I also have a one cylinder 50hp Force that weighs about 195 pounds. I was wondering if the 10 extra hp is worth the extra weight.

[Robby321]

I recently bought an 11 1/2 foot Invader style boat. I have a 40hp Mariner, 2 cylinders and about 150 pounds. I also have a one cylinder 50hp Force that weighs about 195 pounds. I was wondering if the 10 extra hp is worth the extra weight.

I never heard of a one cylinder 50HP Force. And Mariner is a better motor anyway, hands down

[4fiddyR]

I had a '74 with a late 70s 65 horse merc tripple on it. It had a 3 blade cleaver, don't know what pitch. Also, it had one of those huge whale tail things on the cav plate. I tried running it without that once, and scared the crap out of myself and my passenger. To this day, I don't know what happened. All I know is it was scary and I limped back to shore and put the tail back on. I glassed in a battery tray and fuel tank mount way up in the front because I could not get a holeshot and some decent speed with too much weight in the back. I tried a regular prop which gave me a unbelievable holeshot, but I could not steer AT ALL. It would just keep going straight, even with the wheel cranked. The only way to get speed and be able to steer was with the cleaver. The transom started coming apart and I discoverd it had been previously repaired with Bondo (not kidding). I started to rebuild, and add a manual jack plate to get the motor a little higher, and put stiff cable steering on but divorce happened and the project never got done.

[Malidrag]

Well I kind of got away from the Invader. Ended up building this over the winter. Thanks for all the advice.

[KG4]

Malidrag,That is a cool looking tunnel.Is that one from Bob Dillions plans? Very nice.

[Malidrag]

Yup its a Dillon Pro Tunnel. Pretty easy to build and a whole lot of fun to run. Got a 35 on it and at present getting 44.7mph on gps.

[Chips overboard]

those boats have plywood coring and are usually wet and very heavy. Before you glass anything in you should do a little more investgation into the coring and see if its all wet. redoing it would get quite a bit of wieght out.

Nope Balsa core

[richyrose]

FWIW I just did a complete makeover my 10' GW Invader including installing a 2023 40HP Yamaha 4 Stroke with 20" shaft. I ripped off the top and cleaned out all of the old balsa core and replaced all with NidaCore honyecomb and replaced all wood stringers with glass/foam stringers. (there is no wood left on this boat) and it's about 90 pounds lighter. The 4 stroke is HUGE and HEAVY but crazy fast and immediately jumps to plane. I have 16" and 19" pitch SS props...experimenting with both. The main thing I had to do to compensate for the weight was to add trim tabs othewise the bow stuck straight up at idle speed and porpised at high speed. I am happy to help with any questions you may have. Cheers!

[MikeTrine]

FWIW I just did a complete makeover my 10' GW Invader including installing a 2023 40HP Yamaha 4 Stroke with 20" shaft. I ripped off the top and cleaned out all of the old balsa core and replaced all with NidaCore honyecomb and replaced all wood stringers with glass/foam stringers. (there is no wood left on this boat) and it's about 90 pounds lighter. The 4 stroke is HUGE and HEAVY but crazy fast and immediately jumps to plane. I have 16" and 19" pitch SS props...experimenting with both. The main thing I had to do to compensate for the weight was to add trim tabs othewise the bow stuck straight up at idle speed and porpised at high speed. I am happy to help with any questions you may have. Cheers!

I have some questions regarding your rebuild are you on FB?

Thank you!!

[RONNIE]

Nope Balsa core

i had an original GW, It had plywood core that was all rotted when i removed it 30 years ago while i was restoring it