1968 Rayson-Craft 18' Jet Resto Project

[Patchman]

think.gif :smile26:

 

[SyTy Speed Shop]

Ok, I was thinking I'd just buy a set of the SCAT pro comp I-beams with the ARP bolts since I hadn't been able to find deal on a god set of the GM Dimple rods plus everyone says don't bother buying and reconditioning the GM rods cause the aftermarket rods are better. 

Well today I scored a set of the GM Dimple rods, they have brand new ARP 7/16 wave loc bolts, new Manley bronze bushings and they have been resized, magnafluxed and the beams polished and they are weight matched at 842 grams.  I got them for 200 bucks so I think I got a great deal and these are originally from a 502 crate engine and are the GM 4340 heavy duty rods they currently sell for 130 each so I think they will be just fine for my build at 6500 max rpm.

I also scored a deal on a slightly used quick fuel 750 blow thru carb that was only used a few months, it's off Daryl Graffs twin turbo LS powered boat that made 800-850 on 10psi so I think it will be a great starting point for my setup, got the carb for 300 bucks!!

It's all starting to come together!

How much boost are you thinking it will make?

Well the D1 is rated at a max boost of 32 PSI, the pulleys i have, 7.75 crank and 3.70 blower will put the impeller speed at 60,400 at 6500 and max speed is 65K.  I really dont know where my boost psi will be, but on a 454HO Merc Marine engine with a carb, using a 7.75 crank and 5.0 blower pulley it makes around 5-6PSI, so im thinking my pulley setup should be in the 10-12PSI range and around 700-750 max power range, but really its all a guesstimate.

My plan is to use a bypass valve and keep the boost around 5-6PSI in the beginning to get the tune dialed in, and also allow me to get used to the boat, and see how the boat likes the power and slowly raise the max boost as i go along, at this point im thinking im going to limit my max boost to the 10-12 range, but will have to see how it handles the boost once its up and running, eventually im also going to ditch the stock iron heads for a set of AFR's so that will change things as well on max boost and tune up.

What kind of fuel?

93 pump gas, static CR of 10.0:1

You might want to check this out.  http://goodvibesracing.com/Compression_Ratio.htm

god info, but cam specs play a big role as well as if your running rich or lean, lean is mean but to lean can detonate, alittle on the fat side is safer.  I talked to procharger several times and they said with a max engine temp of 160 and running an intercooler with a blow thru carb that acts as an intercooler as well that i would be fine with 10.0:1 static CR on 93 pump gas, now i could have the pistons machined down even more to lower it to 9.5:1 for alittle extra safety margin, but i dont want to compromise the piston either, they are solid domes thought.  Will check them out once i get them in a few days. 

Also, that chart isnt taking into account that with higher boost your going to be retarding the timing so detonation becomes less of an issue as well.  I mean look at steve morris racing, they are running a 540 BBC with 9.5:1 Static CR on pump gas pumping 13PSI and making over 1200HP WITHOUT an intercooler on a blow thru carb. 

 

[Patchman]

So how is the hull coming along? :smile21:

 

[Disturbed]

I don't know if this chart would apply to a blow-through set-up but, it might be something to consider.

http://www.rbssuperchargers.com/The_Guide_to_Carburetion.cfm

 

[SyTy Speed Shop]

I don't know if this chart would apply to a blow-through set-up but, it might be something to consider.

http://www.rbssuperchargers.com/The_Guide_to_Carburetion.cfm

That chart and website seems more for the traditional roots style blowers and a suck thru carb setup which is completely different than a blow thru setup.  Both can work well, the difference is with a blow thru you can support alot of power with a single carb.

 

[SyTy Speed Shop]

So how is the hull coming along? :smile21:

I honestly haven't made much progress.  i have decided that for now i am going to sand it down and am going to re gel coat the outside with two or three coats of just some plain white gel coat, and add the wax on the last coat.  i am going to some light sanding on the inside and lay down one or two layers of fresh glass and resin to help strengthen it a bit and just make sure everything is tied together like its suppose to, then im going to put one or two layers of white gel-coat on the inside and then lay down some nice plush marine carpet.  I have the front bucket seats, and may just run with them in it for the time being as the rear bench seat would just be empty.

But with this crazy as weather we have been having, i don't want to get to far into the hull with the boat sitting outside in my driveway, and i cant fit it into the garage right now, so i have a plan of attack, just no place to put the plan into action.  I was going to move it to a covered storage down the road for 55 bucks a month, but they haven't been complaining about it so i figured id save that 55 bucks as long as i can.  I'm slowly gathering parts, so that once i get a covered spot or im hoping to buy a house in the next few months and it will go in the garage it wont be long to get it done.  The hull is very solid and wont take much work, then i still need to get the pump pulled out, and decide if i want to pull the intake from the bottom and reseal it all up with new hardware or just leave it, im leaning towards pulling it to to know its sealed up.

 

[customtouch]

So how is the hull coming along? :smile21:

You don't need no stinking hull. You just need to have a running engine on a stand!!!  :smile30:

 

[Patchman]

So how is the hull coming along? :smile21:

You don't need no stinking hull. You just need to have a running engine on a stand!!!  :smile30:

I should have known you would see it that way! crazy.gif crazy.gif :smile17:

 

[SyTy Speed Shop]

LOL, well im slowly getting to that point, although i would dare try and run this beast on my engine stand LOL

Instead of the Lunati cam, im thinking about stepping up to a Steve Morris Stage 1 cam designed for a procharged BBC, its a hydraulic roller, 240's/250's dur@.050 .500's lift range with stock 1.7 rockers.  They dont give exact specs till you order one, im waiting to hear back right now.  Says its 800-1200HP with a blow thru procharger and no intercooler.

 

[Knotty Girl]

So how is the hull coming along? :smile21:

You don't need no stinking hull. You just need to have a running engine on a stand!!!  :smile30:

It does sound good on the stand.  :smile30:

 

[SyTy Speed Shop]

Another thing I've been wondering about is when it comes to connecting the drive line to the crank, due you use a std auto flex plate or a manual trans type flywheel for the starter or does it matter?

I'm looking at a BBC M4 balanced aluminum anodized flywheel that looks to be a neutral balance that I need for my 427 build and it looks like it's neutral in the pics.

What do you guys think?

https://www.ebay.com/itm/122286306944

 

[Nitro Neil]

Another thing I've been wondering about is when it comes to connecting the drive line to the crank, due you use a std auto flex plate or a manual trans type flywheel for the starter or does it matter?

I'm looking at a BBC M4 balanced aluminum anodized flywheel that looks to be a neutral balance that I need for my 427 build and it looks like it's neutral in the pics.

What do you guys think?






https://www.ebay.com/itm/122286306944

FL350  Stacy, is your man on that question

 

[SyTy Speed Shop]

Another thing I've been wondering about is when it comes to connecting the drive line to the crank, due you use a std auto flex plate or a manual trans type flywheel for the starter or does it matter?

I'm looking at a BBC M4 balanced aluminum anodized flywheel that looks to be a neutral balance that I need for my 427 build and it looks like it's neutral in the pics.

What do you guys think?






https://www.ebay.com/itm/122286306944

FL350  Stacy, is your man on that question

turns out the one i was looking at was externally balanced so no go.  But i think im just going to run an SFI spec'ed flexplate and then ill need a PTO adapter to connect the driveline so i think i got everythig between the crank and the pump figured out.  LOL

 

[SyTy Speed Shop]

Ive been on the hunt for a set of gas tanks to replace the original fiberglass tanks mine has and finally found a set in OKC, they are currently in a 70's Mariah and are 15 gal tanks vs my stockers at 19, but with them being metal the smaller capacity will keep overall weight about the same i believe, and 30 gals total is probably good for a day on the lake depending on how hard i run it...LOL

Best of all i got the pair for 200 bucsk!!  Will post up some pics when i get them.

 

[SyTy Speed Shop]

Ok, got a serious question for the BBC gurus.  Ive been looking for a vintage 4pt engine mount setup that i feel would really fit my 68 nicely, and Ive found a guy on ebay that has a complete kit but since its vintage its designed for a Mark 4 block.  Ive got a Gen6 block and a Dooley oil pan designed for the 1pc seal block, i also ordered a decently nice polished aluminum gen6 timing cover.

The vintage 4pt engine mount kit is made my Edelbrock and i know the rear mount plate/bellhousing will work reguardless as they are the same, but the front mount plate has the timing cover built into it.  So, i want to know if there is anyway to modify the front mount plate/timing cover to make it compatible with my gen6 block? I already know i can drill and tap the block for the timing cover mounting bolts and thats not a big deal, just wondering about the oil pan area.

Heres a link to the kit im looking at.

http://www.ebay.com/itm/201840004642?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

[FL350]

Way to much modifying. Probably would never seal. Those mounts look like there for a vdrive also.

 

[SyTy Speed Shop]

Way to much modifying. Probably would never seal. Those mounts look like there for a vdrive also.

Is there any reason why they wouldn't work in a Jet application, and i think im going to swap to a Mark IV block and do a 396 build, as my boat was originally offered with either 427 ford or 396 BBC power. Ive got a line on a nice 68 396 block that is STD bore i believe.

 

[SyTy Speed Shop]

Ok, time for an update.  Those Edelbrock mounts i was looking at on ebay got up over 400 bucks and i wasn't willing to spend that much so i let them go.  Been looking everywhere for something similar without much luck.  But i did score a virgin bore 68' 396 block that is a 2 bolt in great shape, i also scored a milodon splayed 4 bolt main cap upgrade kit off ebay for it for like 80 bucks shipped!!  Ive also scored a sweet deal on a set of 100cc chamber Edelbrock aluminum heads, and have 2.19 intake and 1.89 inconel exhaust valves and  a Lunati dual spring kit and Lunati aluminum rockers and ARP studs to get them built, i bought them bare so they need a valve job and im gonna have some mild port work done as well, got a weiand track warrior high rise single plane, this thing is super clean on the outside of the casting but the inside has alot of casting flash im gonna have my head guy clean up and port match the heads and intake.  Ive also got a set of Lunati Signature Series roller lifers, and i haven't ordered the cam yet but it will be a Steve Morris stage 1 cam that will be somewhere in the 240's/250's@.050 with high .500's lift and not sure on LSA.  and lets not forget the Procharger D1 that will be hanging off the side!!  I don't think i will have any issues making power or going fast!  LOL

But back to the mounts, i was starting to look at glenwood marine for some new ones, but at almost 600 bucks def not a cheap option and the rail kits were looking better and better.  But a few weeks ago on ebay i came across another 4pt mount set, this is a Nicson front and rear plate, guy had it listed at high 400's and i wanted it for a week or so an he dropped the price alittle and then i made an offer of 250 thinking he wouldn't take it but he did so yeah i got some mounts that will hopefully work.

Well i got the mounts in yesterday and super excited to see how they fit and i was super stoked when i set the rear plate up against  the feet that were left bolted to the stringers from the old engine and the bolt holes lined up perfect and the center of the rear plate was pretty much centered over the input shaft of the pump.  Set the front plate in and same thing, bolt holes lined right up and the front of the engine would be alittle higher than the rear which is what you want in a jet boat from my understanding.  I then set the 10qt Milodon oil pan i got for the 396 block to see if it would fit and i think its gonna be close at the back between the bottom of the oil pan and the pump intake, but i think it will work, maybe have to trim down the intake studs just a bit to make them flush with the tops of the nuts.

So again super stoked and i think these will work great.  Im gonna bolt them to the engine and mock everything up in place.  Def getting excited to get this thing going on the water!!