Opinion for 525hp small block build

[idahogrumpy]

OK here's the deal, My friend wants to build a 525 hp streetable  91 octane small block for his A Body.   He does not want a big block, He wants to assemble this with my help. I would like some input on building such an engine. I have read the book how to build hp small block mopars, and would just like some input from here. This will be a ground up build, no parts have been acquired. It is already understood that this will need to be a stroker, good aluminum heads, four bolt mains, forged crank, rods, pistons and such.

Should we use a LA 360 block, 5.9 Magnum block, R3 block, or a 340 block??  R3 block, 45 deg or 59 deg valve train?  What would be the best heads? Solid or roller cam?  Crank, rod, and piston combination? We do not need over kill here just a solid engine. I am looking for some detailed information if possible. Many of you guys have built many more engines than I have, this is why I have posed the question here.     Thanks Grumpy

[mikepmcs]

Here's a starting point that makes in the 415 range.  And this guy knows his stuff.

http://www.dodgecharger.com/forum/index.php/topic,283.0.html

I'll try to find you more threads, I believe there are a few that cover this subject.

v/r
Mike

[mikepmcs]

more on this subject.

http://www.popularhotrodding.com/enginemasters/articles/mopar/smallblock/0506em_410/

http://www.allpar.com/mopar/318.html

Might want to get this book.

http://www.motorbooks.com/Store/ProductDetails_10476.ncm

Happy building

v/r
Mike

[Bones68charger]

http://www.geocities.com/alwest_83/dyno


This site gives you plenty of combos to choose from, their highest hp rating is 495, but it's pretty close!

[aifilaw]

525 is a big number for a mopar SB if your going N/A and pump gas. It is quite possible, but driveability(if you care) is not going to be good, and you are going to end up spending a lot of money on head work.
You may consider going with a forced induction in my opinion, you will probably spend less in the long run and make the engine more durable.

[firefighter3931]

525 is a big number for a mopar SB if your going N/A and pump gas. It is quite possible, but driveability(if you care) is not going to be good, and you are going to end up spending a lot of money on head work.
You may consider going with a forced induction in my opinion, you will probably spend less in the long run and make the engine more durable.

Ported aluminum heads and a stout cam will be required to hit that number. Then you have to run the matching converter and gears to make it work well together. 


Ron

[idahogrumpy]

As far as the converter and gear it is understood that we will be a little over the edge for a street application. I have tried to talk him down a bit, but he wants the best of both worlds as usual.   If it were up to me I would use a nice 400 block stroker. This is going to be a ground up build in a 73 Plymouth Scamp.

Anybody want to discuss the block options? Pro & cons of various blocks.  I'm looking for some hands on experience here. I have read the sales information and Mopar engine books. Yes I want your secret combinations. I can not believe this will the first build up of this type attempted by anyone here.         Thanks Grumpy

[aifilaw]

oh it certainly isn't...

I'm a BB man myself and keep clear of the chrysler SB's, or used too...to keep from getting confused, so I won't be much help....

But given the criteria, I'd definitely be looking at putting a turbo, or a supercharger on this thing to achieve what he wants. It'll break the bank maybe the same, maybe less...and provide a much better all-around engine/driving experience.

[Challenger340]

I've done quite a few @ 530-550 H.P., using regular 360 blocks, on pump gas, but with "box-stock" INDY 360-1 heads unported.

I have a "EDDY" head 408 on the go now for a guy, pump gas, which should be right around, or slightly over, the number you were talking about for power.
I just use the stock 2 bolt 360 blocks. This particular one we're doing now, we're putting a girdle on the mains, similar to the SB Ferd things we do.
I'll take some pictures of the prepped block tomorrow and post so youi can all have a "boo".

Bob out.

[idahogrumpy]

Thanks for your input guys. 
         Challenger 340, I know you do this for a living.    But, can you please give me a run down of that 360 block combination that you are talking about. I have a 360 core I will give him if it will work ok.   Are you using a hyd or solid roller cam?  I'm concerned with roller cam setup for that block.  I would like to build this engine with a solid tappet cam shaft. You would stay away from the four bolt main upgrade?  If so why?  What compression are you running for that combination?  We had already pretty much decided on Indy heads, but did not know if any porting would be needed with those.  My friend doesn't seem to think a stock 360 block combination will hold up.  I say it will because we will not be running it at high RPM all of the time. I believe with proper setup this engine should last quite awhile for the weekend cruiser and flogging (not with oil ) down the track a few times a year. Anyway that is the reason for the block questions. I'm sure there will be many, many  more.  If you don't mind?   
         
         Aifilaw, I'm with you on the big block thing, I have built several of them and each one being better than the one before. This is kind of a hobby of mine.  I do it for friends, they buy the parts and we put it together. It is fun!!!

         I will try and post a step by step of our progress as beer did with his build up. That may be a very hard act to follow, He did a good job.

                                                      Thanks again Grumpy

[Rolling_Thunder]

We have a 472hp stroked small block in a 1966 dart in the shop currently being restored...      alot of engine for a 2800lb car with 235/60/15's and a 4-speed OD...     

[Mike DC]

--  Another vote to use a big-block for that power number.

--  If it absolutely has to be a smallblock (Why?  Clearance in the engine bay?  I would think a SB that's totally uncivilized for the 525 number will probably be a pretty big pain-in-the-butt too).  Then I agree with the suggestion to look into forced-induction. 

Ever looked into screw-type superchargers, like the ones Whipple makes?  (They're NOT the same thing as a traditional Weiand "roots" type blower even though they look kinda simliar.)  Those things look like the most fun-to-drive blower setup that anyone has yet invented; way better than the centrifugal ones.  With the screw-types, all the blower's power has been added by the time you hit only 2000 rpm.

 

[Beer]

My Build (402 stroker all forged  w/ edelbrock RPM Package) was 414 HP and 466 FT/lbs at the crank, untuned. The machine shop that built it said if I wanted more go solid lifters, port the heads, and get a larger cam.  I could easily be in the 450 -500 range with the head  porting/cam swap. 

[69Chrgr]

OK here's the deal, My friend wants to build a 525 hp streetable  91 octane small block for his A Body.   He does not want a big block, He wants to assemble this with my help. I would like some input on building such an engine. I have read the book how to build hp small block mopars, and would just like some input from here. This will be a ground up build, no parts have been acquired. It is already understood that this will need to be a stroker, good aluminum heads, four bolt mains, forged crank, rods, pistons and such.

Should we use a LA 360 block, 5.9 Magnum block, R3 block, or a 340 block??  R3 block, 45 deg or 59 deg valve train?  What would be the best heads? Solid or roller cam?  Crank, rod, and piston combination? We do not need over kill here just a solid engine. I am looking for some detailed information if possible. Many of you guys have built many more engines than I have, this is why I have posed the question here.     Thanks Grumpy

I am currently building a 360/408 combo. 500 horepower is not out of reach with the right heads. There seems to be a lot of talk as to the performance of the SB. I would challenge most Big Blocks here, knowing my 68 Cuda would hand most of the BB Chargers here there ass, and that's with my old combo. Yes, I'm also building a Hemi 69, however don't underestimate the smallblocks, as most of you may be embarassed.

[Mike DC]

 
I don't underestimate the potential of the LA motor.  With good internals & big enough heads, it's an absolute monster.  A well-built SB can often smoke a mild BB motor.  Numbers don't lie, and there are TONS of fast LA motors out there.

But IMHO, displacement is still king for a fun car.  The BB motors can virtually always hit a given number at a lower RPM than the SB's, and that's what I really like to have for a street car.  Tends to be a flatter power curve from idle on upwards.

 

[firefighter3931]

  Tork Rules....especially on a street car with mild stall and gearing. 


Ron

[69Chrgr]

 
I don't underestimate the potential of the LA motor.  With good internals & big enough heads, it's an absolute monster.  A well-built SB can often smoke a mild BB motor.  Numbers don't lie, and there are TONS of fast LA motors out there.

But IMHO, displacement is still king for a fun car.  The BB motors can virtually always hit a given number at a lower RPM than the SB's, and that's what I really like to have for a street car.  Tends to be a flatter power curve from idle on upwards.

 

Yes sir, you are correct. It's just that in an A-Body, I do like to turn the wheels and actually have the car respond once in a while. Hey FireFighter, I'm still waitin' to settle our debate on Pinks! lol. Let me know when you're ready. Don't worry, I'll give your car back to ya', I'm not that bad of a guy

[idahogrumpy]

Are you using a hyd or solid roller cam?  I'm concerned with roller cam setup for that block.  I would like to build this engine with a solid tappet cam shaft. You would stay away from the four bolt main upgrade?  If so why?

     Boy it seems a little tough to get specific answers to the questions. Anybody ?              Grumpy

[Challenger340]

I should be all wrapped up, done & dyno'd, on this EDDY 408 SB in about a week.

I'll put up the dyno numbers, and the combo, when done.
For the record, we use a solid flat tappet cam. Also, being a pump gas, "driver" type engine, we try for good low end torque, even at the expense of dropping some ponies up high.
IMHO, I have NO issues at all, with the sb "stock block" combos, around the 500 H.P. and Torque. The trick being to get the rotating assembly as light as possible, studs the mains, and call it good.
NOT that aftermarket blocks aren't better, they most definately are. Just that the stock block is satisfactory for those numbers.
I worry far more about the stock block pushing the cylinders walls out, more than I worry about the mains themselves.

Just my opinions on the subject.

[69Chrgr]

When I took my block to the machine shop(Wells Racing Engines), they took a look at the mains on my Magnum 360 block. They said they looked quite beefy, more so than a SB Chevy. They didn't think I need 4 bolt mains for the 500 hp number. Just food for thought. Can't wait to see how that SB 408 turns out Challenger340. Keep us posted.

[Mike DC]

Yes sir, you are correct. It's just that in an A-Body, I do like to turn the wheels and actually have the car respond once in a while.

Yeah, I hear ya on the weight issue!  The BB motors are a handling drawback in a decent optioned B-body, let alone what they do to the smaller cars.  You can put stiff torsion bars in the front end but it's a band-aid.

That's why I REALLY  wish there were some reasonably-priced streetable aluminum cylinder blocks for Mopars.  With a BB setup you could probably get 500+ cubic inches for 500 pounds.  An alloy SB motor would probably do 400+ inches for 400 pounds.

 

[Challenger340]

Still trying to get back on the 408, pics & details to follow, need another week, too damn busy !

Will get ya some details on the whole combo too.

Apologies, Bob out.

[Challenger340]

In the meantime, here's the 408 block prepped with a main girdle. Wasn't my idea for the girdle, but, the customer had it already, so "what the heck".
NOTE; you gotta line hone the block to fity this girdle, as it crushs/distorts the caps real hard.
[/img]

"pump gas" Piston & Rod combo, normally not a Flat-top, but I open and do alot of chamber work, to offset and stay @ 10.5:1
[/img]

[69Chrgr]

What's your plans for the Magnum on the left? Is that the one you're stroking or is it the LA? I'm doing a Magnum 408, a former crate motor. Love the girdle.

[Challenger340]

The block on the left is a regular old 360 Block LA, it is a "new build", for pump gas with EDDY heads, that will come in around the 525 H.P. mark.

The block on the right is a R3 race block, an "old build", using INDY heads, currently just in for re-freshening.

Apologies for any confusion.

Bob out.