A sweet sbb 350 combos if anyone is thinking of building one.

Thanks for all the info Derek. Any suggestions on Pistons? Would it be possible to use Wiesco 5040A3 or JE 131557 Pistons with the nascar rods?

 

Sure if you can get those pistons with a .787" wristpin or if the bushings in those rods can be removed and made to the .940" size.

Do you have the rods yet or are you still waiting for them to be shipped?





Derek

 

Rods were shipped 2 days ago. Going to tear my spare block apart & see how it looks inside. Next week will give the machine shop a call and ask a few questions.

 

The only thing I need to add is to really careful about picking both the bore and stroke. I have checked to see how much stroke could be added and there is very very little room to add stroke without the cam hitting the big end of the rods. I decided to keep the stock stroke there was just not enough room to make it worth the small amount I could stroke it.

Those rods you have are a smaller diameter big end though so you do gain some room there.

If you do stroke it be sure to mock it up before you machine the crank because you only get one shot at it once you commit and offset grind the crank. The only way I can think of too mock it up is to have a spare crank cut on one journal to fit your rod and then assemble with a piston on the rod to see how much room you have to stroke it.

Bobb is the only one I know who has stroked a 350 and he got 369 inches with a 30 thou overbore so whatever that works out to in stroke is possible however who knows if his rods were smaller larger than yours on the big end. They are using the same journal size as you are though so it is a direct comparison.

What ever happened to Andy's stroker engine? Once that one is assembled and checked to see if the cam clears the rods then you will have another comparison.

I don't want to scare you away from stroking the engine but I want to see the rods clear the cam.

I think you will find that it is like finding a needle in a haystack to get an off the shelf piston to work with the rod, end up at zero deck and have the right dish. Keep looking though it is possible but another factor is the valve notches which you really should have so you can use any cam down the road. That's why I say diamond they have it perfected with the notches and can do any pin height you need and any dish you need.

I would for sure do an internal balance. You can use the stock flexplate and balancer which are offset weighted and still have the assembly balanced if you want to save money. Or the optimal way is to use a Sfi rated neutral balance flexplate and balancer and then have a truly internal balanced engine...

I had it easy, I used the Herche rods that are stock spec, had the pistons custom made to give me the compression I wanted. Had the rods and Pistons balanced and bob weights mesured then I just had to have my custom crank made with the right bob weight spec and it can be simply bolted together. I even had my crank journals made exactly the right size so my bearing clearances are where I want them. Just as simple as a phone call.

 

Speaking of the Finishline sbb 350 build, why did it get deleted?!! That was a great thread, why do the sbb 350 threads that show the sbb 350 making power get deleted??!!!

And no the bore would of needed to be more than .030" to get to 369 CID with the .100" more stroke they did with that build, even if they stroked it .150" more that wouldn't add up to 369, would of been more like .060" over.



Derek

 

I will check my notes but I remember it was either 30 or 40 over on the bore bobb used at least that's what he said. 369 cubes is what he said. Not sure why he deleted it, glad I saved it on my computer same as I did with the 1021 hp build before it was deleted. I do know that bobb was not eager to share much info about the build and I do know he was planning to put a bigger supercharger on it. I should call him and see how his 350 turbo builds are going.

 

What's the deal, did he think he found a secret weapon, the Holy Buick Grail perhaps because he cranked that little sbb up to 750 HP and still couldn't break it while with a jock strapped 455 you still don't know if the block will hold up? LOL

Looks like the racers got it backwards, the BBBs should be the street engines and the sbb should be the race engines!



Derek

 

Well it was funny... I was talking to bobb on the phone way back when and he was saying he was going to help his 15 year old son build a 455 for his street car and I said he should build a 350... He said "why would I do that when I have 20 455s in my shop?" I listed my reasons and asked him to please do a 350 as I knew it would turn out great... He said if he had a 350 he would build it but he didn't have one... so I bought one for $150 (heard running over the phone from a 68 jeep wagoner) in his area and paid the guy to deliver it to bobb... Then he called me and said I was a crazy guy but he would build it.

 

I remember that part in that thread, seems like the better sbb threads get deleted and I need to know why incase maybe I should delete all my posts?(not that any of them are good ,just so people think they were, LOL!!)

Why are people trying to keep the sbb 350 a secret for anything that's done to it? Why all the cloak and dagger? That thread was free advertising for Finishline did JW delete the thread or did you have Bob delete it because of your book?

It would make more sense that those engines ended up as complete and utter failures so the threads were deleted, that has to be what's going on here?

Or is it the sbc aftermarket cartel making these guys delete the threads with successful running sbb 350 builds, made them an offer they couldn't refuse? The thing is an after market nightmare engine after all, the factory crank with the rod journal turned down .100" from 2.00" to 1.889" cast crank that can handle 750 HP and the guy wants to put a bigger boost maker on it and make even more with a factory crank, block and heads!! Someone must of got to Andy and made him put his sbb 350 stroker engine on hold, made him a deal he couldn't refuse?!! Why are people trying to keep it a secret, and why are very nice looking disappointing performance parts made when those kind of parts are finally made for it?

What gives?


Derek

 

Any well skilled builder is going to be able to get where builds in the old threads were taken to.
It's more of an issue of "put the $$ in my hands".
I myself like to see those disappear to keep the core costs/availability in favor.
Nothing like giving away your favorite fishing hole.
Admin, please delete this if it is not appropriate.

 

Holy cloak & dagger ****! I just want to build a stronger bottom end to handle more BOOST. This seems to have turned into a ****show.

 

No worries we can help you get your strong engine built, it is not an issue.

 

LOL! Sorry for the rant. Yeah don't worry that thing will be shredding tires, breaking transmissions, driveshafts and rear ends in no time!




Derek

 

Spare block is stripped down & heading to the machine shop this week. Getting cleaned up & sonic checked.
Have decided to go with 60 over on the bore & after taking the crank journals down to the 1.889, I will go an addition .045 for the extra stroke. Once the block deck is squared to the mains, I will order custom Pistons to get 8.8-1 at zero deck. Not sure what cubic inch that will make the motor, but I'm sure it will be plenty!Was thinking of doing a roller cam, but most likely provide Scott Brown with all my cars info & get a custom turbo cam cut.

 

It would be an additional .090" of stroke with the 1.889" rod journal size unless you're limiting the extra stroke to .045"?(.045" per side meaning that if you offset the center .045" you will get 2X that for stroke because the crank will measure .045" more at top dead center and bottom dead center of the circle making it a total of .090" more diameter that is stroke.)

So if you're going to have an extra .090" of stroke and .060" over(Radius squared X PI X number of cylinders X stroke) which would be the stroke divided by 2 which would be 1.93" squared X PI(3.14159) X 8 X 3.940" = 368.85046, rounded up because the . is greater than .5 is 369 CID.

If the sonic test is good enough to go .100" over that would help get even more cubes to combat turbo lag on the low end. Would be 376.53464 so 377 CID, an extra 8 more cubes, if you went with the 1.850" rod journal size(which you can't because your rods are 2.015" housing bore diameter and they don't make the 1.850" bearings for that housing.) and an extra .140" of stroke and an extra .100" of more bore that would yield 381.31299 for 12 more cubes than the 369. Dealers choice, either way should be REALLY fun to drive!!!

The more the over bore the less the valves will be shrouded which equals more flow potential. GL


Derek

Oh yeah, Scott Brown I think can do a custom roller cam for you I believe? A roller would be the way to go if you can manage it.

 

May bad, I meant .025, so a total of .050 instead of the .090 you suggested. I'm just worried about rod clearance issues. I'll see what the machinest thinks too.

 

In this thread they took the stroke out to 3.990" with the 1.850" rod journal size without any clearance issues(none that were mentioned anyway);

http://www.v8buick.com/showthread.php?200499-the-dyno-numbers-are-in&highlight=1021

It was posted that the power was up to 800 HP and killing the TH400 trans and the Chevy 12 bolt rear end when it was last updated.

Those rods you're using are narrower from bolt to bolt than the stock rods, that's why they will have more clearance with more stroke than stock rods. If I remember correctly I think the center of the bolt to bolt distance on the nascar rods with the 2.015" housing bore were like around .125" less than the stock rods which would give you .0625" per side more clearance just from that. Plus with the extra stroke the rod will kick out more when it comes around giving even more clearance.(like a sbc 400 that has shorter rods than all the rest of the sbc engines measuring in at 5.565" vs. 5.70" for ALL the rest of the sbc engines. Without those rods being shorter cam clearance starts being an issue with the 3.75" stroke of a sbc 400.) The rods you have are the .015" shorter than stock 6.370" so they will kick out ever so slightly more than the stock rod would with the extra stroke because of the new rod ratio plus them being narrower from bolt to bolt. So I don't see cam clearance being an issue unless you're planning on some kind of radical high lift high duration cam, but the last time I checked boost cams were kind of on the mild side.




Derek

 

Any recommendations on rod bearings for the 1.899? Kings?

 

Your machine shop should be able to hook you up with the soft Toyota stock bearings for you that will fit your rods, Kings are a decent bearing. (my Federal Mogul bearing catalog is from 1996, LOL, but still a good reference)

To use the nascar hard bearings you should have the crank heat treated to use those. GL



Derek

 

The clevite bearing should be good . they do have several different numbers so they might not all be that hard.