67 Cutlass Freak

OK guys I would like to hear your thoughts about what everyone would want, or how they would build a mid level performance DX engine on a budget. I am colaborating with Milan to build this engine just to see what we can do. When we are done on the dyno this engine will be sold. We plan to use the stock DX crank, we have custom Chevy pin rods, we have a set of ported SB #5 heads, but may switch gears and go with some ported BB heads. Like our last engine, we are just trying to get good numbers using the old heavy metal. We have a Holley street Dominator intake, but if we go with the BB heads we will utilize a Victor. Milan wanted to keep the compression at 9.7:1 to run on pump gas. He was hoping to see around 500 HP. I think we should go a little higher somewhere between 11-12:1 compression to run on race gas. My thinking is why build a DX if you want to keep it low HP, and run on the street? Most street guys won't want to change their hood or cut a hole in it for the Victor to run on the street. We are going to use a roller cam, but haven't decided on hydraulic or solid. We haven't purchased the pistons yet, they will be custom. We need to make a decission on our performace goals. I say go big or stay home. I would love to see 600-650 HP, but the heads will be the limiting factor.
Alright guys so the question is... if you could have Milan build this engine for you, what would you want to see go into it. This engine will probably sell for $9,000-$10,000 so billet crank, aftermarket heads, are not in the budget. What you will get is a dyno proven engine with flow numbers, assembled and ready to rock, carb to pan.
Winter is here - let us know what you think, Dave - The Freak

coppercutlass

Im curious to see what it puts down i always wanted to do a stock crank dx with a big bore like .030 425 pistons. I like the fact its not getting stroked out. I spare the find used parts bit lol. im sure this build will shine beyond what anyone would think as its been proven by your previous efforts with milan. I guess the only thing i would take serious is if its a mild level performance build make it for pump gas.

67 Cutlass Freak

Freak wrote: "how they would build a mid level performance DX engine"
Not mild amigo!

coppercutlass

Mid level means mild lol. Kinda like taco bell hot sauce you got green mild and fire lol.

captjim

All due respect I think the premise is faulty. You don't need to spend $10,000 to make 500 HP, build a 496. Or, build a high rpm 355. Either will get you there for less money and effort, IMO. Also, ten grand and iron heads??? Just does not make good sense to me. Want a max-effort race engine? Sure, do the DX, but
"mid level performance DX engine on a budget"
just does not go together, IMHO

cutlassefi

I'm interested to see this because of my own experience.
I did a DX a couple years ago. 434ci with Edelbrocks, Victor, 10.0:1 and mild hyd roller. It made 471 measured, 510 corrected.
With a deficit of approx 80ci I don't see how your 350ish DX will even come close to 600hp, unless you have really really good heads. Even then it'll be a helluva challenge with iron heads as you mentioned.
Keep us posted on your potential plan though, as I'm interested in any ideas you may have.

wr1970

There you go Dave do the 600 hp. If it can be done you and Milan can do it.

olds 307 and 403

500 sounds realistic, having Milan on board helps a lot. Sounds like street/strip with nitrous in it's future. I would think it would need to rev a lot using the Victor. How much rpm's can that cast diesel crank take?

madmax442

I'd find a good 425 crank and have it worked to get 434-450 Cu in. Add eddy heads with a bigger intake with compression around 10.5:1 and do a nice custom hydraulic roller but that's just me!

oldsmobiledave

If you are going to all the trouble of running a diesel block don't limit the build by running the diesel crank. Use a billet or a 425 crank.

A stroked 425 Steel crank and various bores allow you to build any CID you desire from 434 all the way up to my 470. FYI a 4.30" square bore and stroke will yield 500 cubes and is doable (my next build)

Decide wether an over square or under square combination serves your needs and build it the way you want.

Go big or stay home.

GEARMAN69

Bore it to 4.25 if you can keep the 3.38 DX crank 383 cubes flat top pistons, decked, milled / max ported #5 heads heads and go for 500+ hp solid roller 11:1

cutlassefi

For YOUR information, I've had four DX blocks sonic checked in the last couple of years and NONE of them, NONE would I trust past 4.185, much less 4.300. At 4.185 they would have numerous spots as low as .100 thick. I wouldn't go any thinner than that, especially if you're going to be making any power at all.
Don't assume it can go to 4.300 bore, odds are it can't.

madmax442

Good luck boring it to 4.30! I can't even bore my NASCAR block that much!

olds 307 and 403

Pure sure Dave has a Siamese bore NASCAR block.

madmax442

Mine is non Siamese bore NASCAR block and and from what I've read you can only go a max of 4.250. Siamese bore blocks can go up to 4.350 but I'd start a lot smaller so I had some meat on the bones for a rebuild or two!

oldsmobiledave

You assumed that I meant doable with a D or DX block. I should have been more clear. I am not using either for the 500 CID SBO. My apologies for not taking the time to be more specific.

I agree with you that 4.185" is a safe bore on the D and DX. With the 4.30" stroke that I am using that combo yields 473.2 CID. My build uses a 4.168" bore which was very safe on my block and left plenty of meat for any future clean up work needed.

coppercutlass

I have seen a stock crank dx go 10's

67 Cutlass Freak

Jim I don't think you have done a DX build yet have you? I added up all the parts and machine work last night and it was more than $10,000 and Milan puts these engines together for the fun, and challenge of it for NO MONEY!

That does include all the little BS, hardware, WP, distributor, big dollar carb. To throw aluminum heads at this engine would just send the cost up higher, and not perform any better without additional work. The SB heads I ported for this engine flow as good as the Edelbrocks out of the box, and blow the Pro Comps out of the water.
Some others have suggested stroking a 425 crank. Milan had a friend that just went through this. After balancing the cost was more than $2000. At that point a billet crank makes more sense. Sounds like we will be staying on the conservative side, shooting for 500 HP on pump gas. This thing should be a hot little, high revving street sleeper. We still have some challenges to overcome. We are leaning toward mechanical roller cam.
Thanks for everyone's input, Dave - The Freak

orange442

Dave, you need to be more clear. The name of this thread is "DX build recipe". You talk about a diesel block and your previous 470 build and then your new 500 build all in the same reply that it is "doable". You never say anything about any other block other than a diesel block. You will probably confuse a lot of people if you are not more clear about your builds. This lack of clarity and specific information just muddied the waters when people are looking for useable information when they are trying to build a D or DX.

madmax442

Having a stock 425 crank cut down and balanced at just over 2k is still cheaper than the $3500 you most likely would spend on a custom made billet crank. No need to go that route unless horsepower levels are over 700 or so.

If the heads you have are already done and flow better than aluminum then use them but I suggested using aluminum because of the fact you usually can get a bit more compression and the weight savings is nice too!

oldsmobiledave

I realized that my post was incomplete and that is why I had apologized and stated that I needed to be more clear. Not sure why you needed to quote my clarification and apology and then tell me exactly the same thing.

All of my other points are valid. You can build a SBO stroker to a wide array of displacements and in excess of my 470 CID using the D Or DX block and a stroked 425 crank. Engine builders like Mark and others are doing this and as with any build the advice and guidance of experienced Olds engine builders should be sought out prior to building. Fundamentals like sonic checking the block prior to boring naturally apply.

To me building a D or DX engine with the diesel crank is time poorly spent. But those who want to do it go ahead. It's your money and your engine so you get to decide how it is built. Best of luck.

captjim

I did not mean to imply that he was somehow being dishonest, my apologies if it came off that way. I just meant that ten grand is a LOT of money for an engine with 40 year old iron heads. JMHO. As Dave and others stated, building a DX with stock stroke and leaving the extra stroke and subsequent cubes on the table seems silly. Build a max effort DX, or just build a regular 350 or 455, either will get you where you want for a lot less money and hassles, IMHO.

orange442

Because you did the exact same thing over on ROP in the DX build thread.

captjim

Could not have said it better, agree 100% When you factor in the extra cost, it is like 15% more money, for that you get a MUCH better piece, along with the added cubes, TQ, and HP. As I always say, it isn't what is right or wrong, it is just a matter of it being a cost effective upgrade. IMHO.

oldsmobiledave

Correct I said with the right block in both places. At least when I make an over sight I am consistent.

cutlassefi

I for one would like to see the sonic check sheet on ANY Olds block that you can take safely to 4.300. And when I say "safely" I mean wall thickness of .090 or better after boring.

oldsmobiledave

Mark it is the factory experimental block I bought from Gregg Godon. It has been discussed on here before. I too doubt that any regular production block can go to 4.30" bore. Thanks for your vigilance. I never should have mentioned it in the D DX thread and won't again.

wr1970

Why can't we just be happy that someone is doing something different and see the results.The foundation parts have been explained and why they are using them. I am waiting on results.Enough said.

captjim

This is the first sentence in the first post,
"OK guys I would like to hear your thoughts about what everyone would want, or how they would build a mid level performance DX engine on a budget."

If he has decided what he wants to do and post a "build" thread, fine, but he asked for opinions and he is getting them. Nobody is being rude or insulting.

cutlassefi

Ya think?
Just an fyi, your credibility isn't great, at least with me. Maybe it's because you have a tendency of talking out of both sides of your mouth, as well as being very vague at times. Just sayin, sorry.
Thanks.

1970-W30

I'm sure you meant except the 403 Olds since they are 4.351 to start with......

wr1970

Jim i am sorry Dave did post them thoughts on ROP. I forgot to link the thread. My bad and thanks for pointing it out. Dave went into more detail over there. Not saying anyone was being rude. I think there is a little dis-harmony between some posters not by me though on this thread.Have a great thanksgiving.

67 Cutlass Freak

Hey guys,
Happy thanksgiving.
Thanks to all for your input. Here's a link to the thread on ROP -
http://realoldspower.prophpbb.com/topic9669.html

I started these threads to get opinions on how others are doing DX builds. I'm not trying to start a **** storm. Milan asked me to do this, he thought I could word it better. He is a man of few words. He is better known for posting facts, and data sheets. I am better known for posting run on sentences, and long paragraphs full of dribble. Milan is the leader in this build so I am doing what I can to help him. I don't have a lot of extra money, but I can invest some time to help out. I tried to convey the premise of what we have for a foundation, and try to work from some of what we already have. Milan just picked up the block from the machine shop, that bill was over $2000, which does not include boring or the core block. We are trying to put this together with a decent budget since we don't need this engine for ourselves. It will be sold. We put the feelers out with some forethougt that if someone wanted to do a DX build right now he could get in on the ground floor, and have a huge input in what direction he would like to see this engine built. I am not opposed to stroking a 425 crank, but that's not my call. From what I have seen the deisel crank is plenty strong to hold up to 700 HP. There's guys running them into the nines without issues. I am not opposed to running Edelbrock heads, but then shooting for 500 HP, with stock stroke, seems like a waist to me. The Pro comps still have too many issues with guides, and other inconsistancies. I love porting aluminum. It's gravey work to me. I think Milan has decided to keep it street friendly, to run on pump gas. This is probably a wise decission for longevity, and sale-ability. Looks like we will be going with a solid roller, and the SB ported heads. We are going to spin it up to at least 7000 RPM, so I hope the Street Dominator will support the flow needed. Things may change but we will keep you guys in the loop.

I posted this over on ROP so I will repeat it here:
If you guys would like to switch direction on this thread, and post up your proven D/ DX builds, I would be cool with that. Let's stick to the facts. Post up parts lists, flow numbers, machine work/ total cost, dyno numbers. We could all use this thread as a how to build a DX and what it takes, if you guys want.
Check back later for our progress, Dave - The Freak

coppercutlass

here is a dx stock crank powered car. I belive in this pass the was n/a i remember him not having the nitrous on his car until much later. It is the car in the left lane. I belive it was a 369 ???? I also owned that white car for a shor period of time.

cutlassefi

Explain if you would, first hand experience? You're a smart guy Dave, I hope you're not taking someone else's word on this.
Four sets, no issues. Ask Bernard as well, pretty sure he'll tell you the same. And at the very least you simply replace the guides and move forward.

coppercutlass

Im gonna play devils advocate and say that based on milans past builds which i think put to shame many many many other builds He and Dave can do it. I personally like the fact its totally different. Anyone can go big but i think it takes someone special to make it happen within certain parameters. Thats what will impress imo. I think milan has built some iron headed engines that have put to shame many engines with aluminum heads. Didnt he build a 450 hp 455 with non ported iron heads ,pump gas or something like that if i remember correct ??? I think i told dave (the freak ) this a while back but if i built a dx i would build it with a stock crank so i cant wait to see what these guys come up with.

67 Cutlass Freak

Mark, I have talked with Bernard extensively. I have purchased a bit of stuff from him. I trust him fully. He has told me of some issues, and problems that he has seen with these heads. I really don't want to discuss it here. Those conversations were private. I do not want to bad mouth the Pro Comp heads. I would never purchase them from anyone but Bernard. I do have a good friend that purchased a set of CNC ported Pro Comps that had to have new guides after 1500 miles. Installing guides isn't a big deal, and only costs about $250 with parts and labor. Then you also have to redo the valve job. Add in the cost of gaskets, and other misc stuff, probably comes to $750. Not to mention the labor to yank the heads back off then reinstall them. This seems like a big hassle to me. Comes down to the inconsistancies in the materials being used. The Pro Comp valve stem thicknesses are all over the place. I have seen this first hand. I have seen the Pro Comp heads personally, and the overall finish looks pretty good compared to the Edelbrocks. I have also heard there is more material in certain areas for porting. I personally have not installed them on anything. I'm waiting for down track results, and more people to report back with their own personal experiences, good or bad. Feedback from guys like you Mark is what we all need. If someone wanted me to port a set for them, I would be happy to. I would not purchase a set for one of my own builds primarily because I also prefer to support American made products. It's not always about the bottom line dollar for me. Sometimes you do get what you pay for.

cutlassefi

WOW! $750.00 to replace guides and gaskets etc! You need to go to someone else then, that's ridiculous.

My point? If you know the guides are suspect, then you replace them right away. And I said buy a set of bare Procomps I believe so their potential valve issues are a moot point as well.
Out of the box Procomps from Bernard, 493 hp. Vs. yours and Milans' BBO build that had ported heads, way more cam, better headers, a single plane and more carb that made 527 and less torque. At the very least I'd say that's competitive wouldn't you? And as the head porter you are, wouldn't the added material be a plus?

I talk to Bernard every so often as well, not sure what you would need to keep private. He's pretty up front and honest with everybody.
Again grab a set for yourself, and go from there. Don't be influenced by me or others, you're smarter than that. Keep an open mind on other potential options that would stay in your $$$ range.

67 Cutlass Freak

I will say this again, this is primarily Milan's build. He has a ported set of #5s I did in hand. I will help him any way I can. I think he likes showing the capabilities of cast iron. There is scientific data that shows cast iron retains heat better than aluminum. The heat translates into power in the combustion process. So with that being said if you had a cast iron head vs an aluminum one, that were identical in port configuration, valve size, combustion chamber, and every other component was the same... the cast iron head would make more power.

Mark I would love to hear more details about your DX builds, and also any cam recomendation you may have. I have a JM 5-1 solid roller we were thinking about using. We may even consider having it turned down. It is over .7" lift intake and exhaust.

oldsmobiledave

Mark does this mean that I shouldn't expect a Christmas card from you this year? Thanks for your performance review on my character and knowledge. That and $2 will get you a $2 coffee.

In future I suggest you don't read my posts since you have a personal problem with my contribution to this forum.

Meanwhile back on topic for the rest.