My BBF

View previous topic View next topic Go down

My BBF

Post  Bmelton on January 19th 2017, 11:16 pm

OK, so lets jump right in!  My little fox body is getting some much needed work.  I have decided to go big block, and I have a few parts wrangled up.  When finished, the intentions are to run 6.0/6.5 Class when it is being run, and PRO No box when it is not.  One thing for sure is that this will be running Holley EFI. Car will be running solid motor mounts + motor plates front and rear (overkill) So with that being said...

I have:
D9TE Truck Block and Rotating Assy (Definetly not using Rods/Pistons)
Edelbrock 60669 Heads
HArland Sharp Rockers
Edelbrock Victor Intake, Injector Bungs and Elbow/TB

Now, with that out of the way...On to the bottom end build.  I am up in the air whether or not to go with a Forged 6.605 Rod and stay with the stock crank, or go with a stroked Crank.  Something along the lines of a 4.3 stroke.  I hate to spend the money on a set of forged stock length rods and have the crank fail on me down the road. But If I am going to buy a forged crank, it will definitely be stroked (why not!)  I know I am shooting for a 6.0, but truth be told I would like to be able to run a 5.60 or so.  Will the stock crank hold up?  It would save me some money.   It would get ARP studs, forged rods with ARP bolts, and a really good light weight forged piston.  If I do stay with stock crank, I would do my best to not turn it too far past 7200.


So what should I do?  Try to save some money by using my crank, and maybe regret it down the Road...

Or Go ahead and buy a forged stroker crank and have peace of mind...  


And in a max effort build, will the block or the crank break first???
avatar
Bmelton

Posts : 10
Join date : 2017-01-17
Location : Bowling Green, KY

View user profile

Back to top Go down

Re: My BBF

Post  rmcomprandy on January 19th 2017, 11:38 pm

A stock crankshaft will hold-up however, it still has a stock, overly large pin diameter.
How heavy will your car be ...? At 3,100 pounds you'll need just over about 700 horsepower.

The studs are a waste of time; stock bolts work just as well; even better in some cases.

Is there a cubic inch size you wish to have using that production crankshaft ...?

At 480 inches inches I would offset grind the stock crankshaft to 3.970" stroke with 440 Mopar size OR, just over 500 inches then offset grind the crank to 4.140" to Chevrolet diameter crank pins.
Of course use aftermarket rods and pistons to match.  Use as high a compression ratio as you can get under 14.5/1.

Definitely port the heads and manifold or at least port the head flanges to a "Victor" port match.

This will be nowhere near a max effort type engine with those cylinder heads.

Look in the "Proven Builds" section and read what it will take for almost every level of power.

rmcomprandy

Posts : 4695
Join date : 2008-12-02
Location : Roseville, Michigan

View user profile http://www.rmcompetition.com

Back to top Go down

Re: My BBF

Post  Bmelton on January 19th 2017, 11:55 pm

Car will push 3200lb. It is a mild steel cage car with all metal except for hood...

Have no cubic inche in mind, but I do know I will either leave the crank at 3.85 or buy a new forged crank, probably 4.3inch. I can't see spending a ton of money on the stock crank.

Also I know I am going to be asking alot out of these heads...But it's what I have, and what I'm going to use unless I find another set of heads at a really affordable price.
avatar
Bmelton

Posts : 10
Join date : 2017-01-17
Location : Bowling Green, KY

View user profile

Back to top Go down

Re: My BBF

Post  BBFTorino on January 20th 2017, 12:10 am

As said already, the stock crank will hold up to almost anything you can throw at it, but it is limited to being stroked to 4.150 I believe.
At 3.85 stroke, it is very strong because it has a lot of journal overlap, thus less 'flexing' and twisting. But at the stock stroke, you almost have a large displacement small block!!....meaning, its got a large oversquare dimension (big bore / short stroke). I've ran my 472 to 8200 before (7700 on stock rods!! LOL).

For price and convenience though, it makes sense to buy a complete rotating stroker kit!! Bigger is better, you don't have to twist it as hard as a smaller motor.

BBFTorino

Posts : 325
Join date : 2015-12-31

View user profile

Back to top Go down

Re: My BBF

Post  D. Sea on January 20th 2017, 8:13 am

If you are going to incorporate a front and mid engine plate then there is no need for motor mounts. They will just get in the way.
avatar
D. Sea

Posts : 2705
Join date : 2008-12-02
Age : 48
Location : Kentucky

View user profile

Back to top Go down

Re: My BBF

Post  away on January 20th 2017, 11:00 am

Or you could just buy my spare 521 short block from me ready to go lol pm me if you want to know details. We are close too. we are only 2 hours away from each other. You could come look!

Adrian
avatar
away

Posts : 179
Join date : 2009-10-08
Age : 39
Location : Harrodsburg KY

View user profile

Back to top Go down

Re: My BBF

Post  IDT-572 on January 20th 2017, 12:10 pm

To run 5.60 @ 3200 # is going to take around 900 hp.

You may want to rethink your plan unless Mr frosty is summoned.

It takes a set of P-51's on a 557 @ 14:1 with a ported intake to make 900 hp.

Easy build to do.
avatar
IDT-572
BBF CONTRIBUTOR
BBF CONTRIBUTOR

Posts : 4527
Join date : 2008-12-02
Age : 56
Location : Shelbyville Tn.

View user profile

Back to top Go down

Re: My BBF

Post  Bmelton on January 20th 2017, 12:41 pm

Yea, I was planning on running nitrous even in the 6.0 class. Hopefully it won't be needed in the 6.50...

Ok so my heads are going to be the limiting factor. The head flow seems to pick up on both intake and exhaust side all the way to around .650 lift where the exhaust hits a wall. I am quite confident that I can muster out some more flow on the exhaust side, it won’t be much but any will be beneficial.

So I am basically hung up on whether to go to a 4340 crank and gain some cubic inches and not turn the engine so hard…

Or I could stay with the stock crank and turn the engine harder, as it should stay together with forged rods and pistons with good fasteners.
In my mind, to gain the power up top, typically the cam has high lift with a lot of duration. This in my, opinion isn’t favorable of staying with the stock stroke and trying to make power from 5000-7500.

Is my thinking correct, the long stroke make more sense to use with my heads? With the valve open the piston can only draw in so much air/fuel though, so maybe up you reciprocate the piston more often, more power can be made. My head hurts.

So after all that it comes down to longer stroke vs. Shorter stoke in a limited head setup?
avatar
Bmelton

Posts : 10
Join date : 2017-01-17
Location : Bowling Green, KY

View user profile

Back to top Go down

Re: My BBF

Post  D. Sea on January 20th 2017, 3:14 pm

4340 4.3" crank IMO.  Your heads will support a 521-534ci engine.

Or buy Away's short block, probably be less expensive in the long run than building what you have.


Last edited by D. Sea on January 20th 2017, 3:15 pm; edited 1 time in total (Reason for editing : Ambidextrous thumbs can't type or spell)
avatar
D. Sea

Posts : 2705
Join date : 2008-12-02
Age : 48
Location : Kentucky

View user profile

Back to top Go down

Re: My BBF

Post  rmcomprandy on January 20th 2017, 7:24 pm

Bmelton wrote:

So after all that it comes down to longer stroke vs. Shorter stoke in a limited head setup?

When cylinder head limited, you could go to the NHRA "Super Stock" practice by making the same amount of power but at a higher RPM with a smaller engine. Then by turning it harder you can put more gear in the car and multiply that power by more.

That takes a lot of tuning work on the chassis to get it right.

rmcomprandy

Posts : 4695
Join date : 2008-12-02
Location : Roseville, Michigan

View user profile http://www.rmcompetition.com

Back to top Go down

Re: My BBF

Post  Bmelton on January 21st 2017, 12:05 pm

I have pretty much decided on stock stroke, 6.8 Rod and a forged piston.
avatar
Bmelton

Posts : 10
Join date : 2017-01-17
Location : Bowling Green, KY

View user profile

Back to top Go down

Re: My BBF

Post  Bmelton on January 22nd 2017, 1:12 pm

Well that just got thrown out the door...My machine guy is really pushing me to go 4.3 stroke, 6.8 rod.  This leaves me with a piston compression height of 1.350    Is this acceptable?  I like the idea of the light weight piston due to the short height, but afraid it may not be nitrous friendly.  Am I just overthinking things?
avatar
Bmelton

Posts : 10
Join date : 2017-01-17
Location : Bowling Green, KY

View user profile

Back to top Go down

Re: My BBF

Post  Lem Evans on January 22nd 2017, 3:19 pm

The 4.30" x 6.800" thing works good. The C.H. doesn't really have a thing to do running NOS.

Lem Evans

Posts : 6834
Join date : 2008-12-03
Location : Livermore , Ky

View user profile http://bfevansraceparts.com

Back to top Go down

Re: My BBF

Post  Bmelton on January 22nd 2017, 4:15 pm

Thank you Lem...maybe I'm on the right track.
avatar
Bmelton

Posts : 10
Join date : 2017-01-17
Location : Bowling Green, KY

View user profile

Back to top Go down

Re: My BBF

Post  t-bird racer on January 23rd 2017, 10:37 am

I have a set of BBF Fox, Swap Motor mounts if your looking to go that route.
avatar
t-bird racer

Posts : 101
Join date : 2010-01-10

View user profile

Back to top Go down

Re: My BBF

Post  Bmelton on January 23rd 2017, 10:44 am

I have an AJE k-member and motor mounts, but am going to use front and middle plates. I have a set of Ceramic coated Hooker headers which from what I hear are junk. Guess I am going to get rid of those in favor of some custom headers.
avatar
Bmelton

Posts : 10
Join date : 2017-01-17
Location : Bowling Green, KY

View user profile

Back to top Go down

View previous topic View next topic Back to top


 
Permissions in this forum:
You cannot reply to topics in this forum