351freak

I have actually taken these steps to the next level... I'll try and get a pic or 2 up of the intake I built for my 408 twin turbo several years ago... It was an individual runner, upper intake for a Edelbrock EFI lower. It incorporated twin intercoolers into the plenums and a balance tube in between. It was fed by twin 75mm throttle bodies. Unfortunately...it was never ran...now just a conversation piece...and without intercoolers (they leaked...my welding skills weren't so good 6 years ago...) My take on this intake was exactly as mentioned...with a caveat... (if I did it again...) Split the intake into cylinder banks...and make each turbo feed the opposite bank...and use a small balance tube. This way...if any 1 of the turbos fail...it kills the airflow to the other bank as well...no chance of pressurizing just 1 side of the block. Call it an "aiflow fuse", if you will...

Kiwi...since your post was right after my last one, I will assume that was where you picked up the term "plenum"... Sorry for any confusion, but my remarks were for an intake plenum and were not intended for anything to do with the exhaust side. I simply want to look into what happens when you "tune" the intake and exhaust using the 180 degree firing order setup and varying runner lengths (intake and exhaust). I will simply "split" the v8 into 2 banks of 4 cylinders with the 180 degree pattern per bank. In my case (Ford Windsor), each bank will consist of the first and last cylinder of each side of the block and the 2 middle cylinders from the other side. And since 2 of the cylinders will have to exhaust along a longer path, I can tune the exhaust of those 2 cylinders to the lower rpm point and the other 2 to the higher rpm point. The question then becomes: do I tune the intake side to the same points (assuming this will make it quite "peaky" at this point) or...do I tune the intake to a common rpm point...or...do I tune the intake to the opposite of the exhaust. My thinking is that if I tune the intake and exhaust to different points (max TQ and Max HP)...then I should get a slight bump at BOTH vs a big bump at just one...and a bump at both should make the TQ curve flatter...which is always good. I've also been playing around with the idea of a variable runner intake design that I want to copy from BMW. I believe my AEM engine management hardware has the ability to control a stepper motor based on rpm...which I could use to adjust the intake runner lengths. Anyway...that's the long term goal. Right now, I just want to get the darn thing together and get it running with what I got. So far, I have put down 411 RWHP thru the AOD tranny and full exhaust (based on David Vizard's design) and I know that there is at least 50 more HP available and possibly closer to 100 if I can get the cam just perfect. Right now, my displacement is right at 5.7 liters and I'm making approximately 500 HP which is about 85HP/Liter. It should not be a problem with the parts I have to get it to at least 100HP/Liter and possibly a little more. We'll see. Can't wait to see what Paul puts together.

Well...I'm back... No good news to tell, though. The block deal fell thru. All of the 50+ blocks were fubar. And with no job, I cant raid the savings anymore for a custom crank and pistons. The small stroke cranks we found for a grand just wont cut it for my application. I cannot give up displacement for rpm. This is going to be as nasty of a naturally aspirated angine as I can make with the heads that I have...and that means about 600HP at the crank...and you just cant do it with a sub 3" stroke without much more expensive parts...and lots of rpm (which the tranny can't handle anyway). So that's it for me...I'm out. I have a new Boss 302 block coming this week and will be moving all my parts from the stock block over. The plan now will be to look at the 180 degree header design and a 180 degree intake with 2 separate plenums as well. I may be able to tune the intake and exhaust to 2 separate points per bank...since I will have a long pair of exhaust pipes and a short pair...I can do the same thing with a sheetmetal intake. Hmmm...1 point at torque peak and the other at HP peak...??? And do I tune the intake AND exhaust of the same cylinder to the same rpm point ...or do I tune the intake and exhaust to different points to give a better "average" fill...??? Will have plenty of math to do when the welder gets fired up. I'll still lurk here to see what's going on and to give updates as I go... -David

Paul... Great news for YOU...not me... I will PM you the details. 1st...my block deal is turning into a nitemare...the sales manager now is who I am speaking with...and even HE can't confirm that there are ANY of the 52 some odd blocks that are usable with a 3.4" stroke. (Honestly...did this company just f#ck up over $100,000 of inventory on a "milling error" before someone cought it...??? ) I will wait to hear back. There are 3 different part numbers covering 10+ different inventory locations...so hopefully someone just hasn't checked them all. We'll see. On the cranks... Jackpot...I just found YOU 2 flavors to choose from... a 2.75" stroke and a 2.87" stroke...straight from the Ford Indy program. Brand new cranks for the picking at the mind numbing price of $1,000 / each. No strings attached. And I was told that these exhibit no harmonics thru 9,500 rpm. Designed for the good ole 302 block. 43 pounds each. Use a 5.5" rod with a 2" Chevy pin diameter and width (fairly common combo). Of course you can do whatever rod/piston makes you happy. My 3.4" stroke is uncharted territory and I was told to expect a rattle box from Hell unless there's more to it...we'll see next week...got some more calls to make. and... I was also told that there really isn't any "benefit" to going 180 crank vs. 180 headers..and the 180 crank way is going to cost more in the long run... BTW...here is a modern Vette with 180 headers...standard crank... pretty much the exact same sound... Because of my stroke issues, I may be going 180 headers instead...we'll see. (side note...my Tranny is an electronically controlled Ford 4R70W (wide ratio AODE) that is fully programmable via stand-alone box and included paddle shift mode...thank you Baumann TCS) http://www.becontrols.com/products/electronicscat.htm Paul...check your PM's...

And another update... 1st...I'm still trying to get info on the cheap block...the sales guy didn't seem too thrilled to have to get out of his chair and actually have to go measure the bore to see it will work for my application. The blocks that I want have been notched for a stroker...but the notch job (that sounded dirty) got screwed and was too deep. If the notch is further than 4.3" from the top of the deck, then it doesn't matter...my piston rings will still be good with a 1.090" compression Ht. If that block is bad...then I'll just step up to the 4.115" bore without notches (I'll notch it myself) and just buy new pistons when it's time. As for the flat crank... Randy @ Winberg finally called back about the Big Block Ford cranks he did last year. He says they were 460 cranks...not FE..but it really doesn't matter at this point. Anyway...he said that although HE doubts the testing procedures were done in an accurate manner, he did say that the LRRL (standard 4 cyl.) crank was deemed by the end user to exhibit the best harmonics by a significant margin...but there was no hard data to back that up...but he did say that he expected this result anyway. He was VERY knbowledgable on the subject and clearly possesed the software and engineering skills needed to sort out all of the details to get the job done. When I told him that another company had said that foregoing ANY counterweights would yield a 22# crank BUT would be very rough, he concurred. When I said that the prior company suggested a target of 38#'s +/-2, he immediately said "I don't know how they got THAT number". Suggesting to me that he would not just throw a number out there without some serious engineering homework...which is why he charges $4500 (+/- $500) for the job...!!! Sooooo...if we can do our homework and come up with the right weight to use (total and counterweights)...then we can get it for $2200 from Rodine... I am also looking at using Titanium rods as well...since I can drop the rod weight from around 620 grams to 335 grams by switching to a Honda 5.394" rod vs. the 5.400" Ford rod... No big deal, if I am going to have a custom crank ground...right...???? Now I have to see what the requirements are for the rods to keep from rubbing/welding themselves together...Titanium doesn't play nice... Heh... 302 Windsor block ($800)...Cleveland mains $0(or windsor...if I use spacers)...custom crank $2k...Honda Ti rods $2k...custom pistons $800... . . . The look on ANYONE'S face when that bitch screams to 8 grand and sounds like a Ferrari... PRICELESS... Will keep it coming as I get it...

Good news version 2.0... Greg @ rodine machine just called back. Said he could do one for $2200.00 in 4340...but it would be a 5 month delivery. He said he would check into it for the balancing issues and could make it as light or as heavy as needed. $2200 is doable for me...given I'll be saving $1500 on the block. If we can get the harmonics situation licked...!!! Found another thread as well...don't know if there are any common members to both threads...but have a look... http://www.gt40s.com/forum/gt40-tech-engines-induction-exhaust/26188-flat-plane-crank-sbf-2.html -David

Alrighty, race fans.... Here's what I've turned up so far: Bessel Cranks - Billet only - 2750.00 - 16 weeks Crower - Billet only - 3000.00 - 10-12 weeks Callies - pass, no thanks Rodine Machine - To call back Scat - Billet - 3000.00 - 20 weeks Lunati - wont call back Windberg - to call back - actually made both style flat cranks last year for the Ford FE motor...said the LRLR version was used over the LRRL...but didn't get to speak with the designer to get details...waiting on call back Cola Cranks - inconclusive...may be out of business ??? Sonny Bryant - 3000.00+ - wouldn't give a lead time FYI - can't remember who it was that said it, but 1 of the companies I spoke with indicated that the stroke I was looking for (3.4") was going to have harmonics @ 6800, 7600 and 8200 and that sustaining that rpm was going to rattle your teeth if held for 5+ seconds. Additionally, he stated that making the crank heavier (approx. 38 lbs vs. super liteweight 22 lbs) would dampen the vibrations a good bit. No solution for the vibrations was recommended. I assume that the shorter stroke in question will move the harmonics up the rpm scale a good bit...crappy for me, though...because I want to shift @ 7,800 and run thru 8,000 with the 3.4 stroke. My heads flow just enuff to make peak power @ 7200-7500 rpm if I can get 110% VE... I may be stuck using 180 degree headers. The good news...found a super cheap bullet proof block...bad news is that it would take a custom crank to work...sooo...do I save $1500 on the block and put it towards the custom crank...??? Gonna run the flat crank Idea by the real hardcore guys and see if the benefits outweigh the troubles...I do like the sound though... -David

Paul, Since I'm a Ford Guy...you know what my vote is... With that being said, I have some info that I would like to share...which may or may not be similar to Chevy offerings... Hi RPM Small block Fords are not new... us mustang guys have been doing it since the 90's for our "street/strip stuff"..although the 9,000 rpm goal is a little higher than the 8,000-8,500 rpm that is typical to our genre... BUT...here are several links that show it can be done, given the correct components... Anderson Ford Motorsport sells "off the shelf" hi rpm cams with mild ramp rates for use with OEM style hydraulic roller lifters capable of going to 9,000 rpm... http://www.andersonfordmotorsport.com/ Here is one of my favorite Hi rpm...Hi Horsepower combos using Andersons cams: http://www.andersonfordmotorsport.com/cars/Marnold359.html And Marc Arnold's website can be found here: http://www.the-arnolds.net/Cobra/ That should give you some ideas on HOW to make the Ford combo work. Just be advised that almost ALL serious Ford guys scoff at the idea of trading HP capability for rpm...the question is always "Why do you want to rev to 8,000 when you can make the same power at 6,000 ??? " If you don't care for "maximum horsepower", then the Anderson cam profiles (like the N-111,112,113) will most assuredly get a smaller stroke, smaller displacement motor spinning to the 8,000 plus rpm range all day long with the correct intake manifold (correct runner length for Hi rpm use). Anderson would just have to grind the stick for the modified firing order. The Anderson grinds are tame by todays standards and much more power CAN be made...but their purpose is Hi rpm power. On engine components, I would think any "good" I-Beam or H-beam rods with ARP 2000 bolts should do the trick and the next stronger bolts most assuredly will. (a 3" stroke puts you @ 4500 ft/min) 5.4" Ford rods are commonplace and 1.3" compression ht. pistons are too... http://kb-silvolite.com/forged.php?action=diam This would give a 1.8 rod/stroke ratio with a standard 3.0" stroke in a 8.2" deck ht. block....using off the shelf components. If you wound up going with an aftermarket crank, you could use: -a 3" stroke 302 crank with Chevy (2.1") or Honda (1.88") rod journals -a typical 1.090" compression Ht. piston from a 347 stroker kit -a 5.596 351 Windsor rod (stock 351 Windsor length but needs journals to match crank) This would get you to a 1.87 R/S ratio and a deck ht. close enuff to play with, even with a block that has been surfaced a few times ( 8.186" deck vs. 8.2" nominal) I'm still going to look into the cranks...but it is probably going to take a while. -David

As far as intakes go...changing the crank to a flat plane style merely changed the firing order. It doesn't change the physics involved regarding induction and wave tuning. It does present the opportunity to take advantage of the now more closely spaced induction waves by allowing separate plenums on each side of the motor...but it isn't a "requirement". Over the next week, I will be discussing intake requirements (if in fact there are any...especially on an unrestricted head (defined as flowing more volume than the engine can physically consume within a given rpm range...which is also defined by the mechanical limits of the components involved.) My current project involves a 347 cubic inch ford that will hold together up to 8,000 rpm...which is where the tranny will hold together as well. The motor will be finished around these mechanical limits...and as it turns out...my heads just happen to flow enuff air to max out at 7500 rpm based on the displacement of this motor @ 110% VE and still leave the requisite shift point slightly higher than the HP peak (which is how it is supposed to be). The sound of this motor thru the x-pipe @ 8000 should be awfully close to that of the ferrari/masseratti (sp?). If I can get my hands on a 180 crank, I should be able to get an additional 3-5% power output based on wave tuning alone...and possibly a broader, flatter torque curve. One thing people need to pay attention to...in the videos and pics in previous posts...are the collectors where the primary pipes merge. NONE of the small displacement/hi output engines (from race teams) use a large collector. They all use a true merge collector that is funnel shaped and then opens back up to a larger collector area..which promotes a rather large scavenging effect. (topic for yet another thread). cant wait until someone finds out where all those can-am 180 cranks from the 60's wound up at...!!! -David

These guys just quoted $2500 for a billet 5140 with 10-12 wek lead time... FYI...some folks call it a 180 crank vs. flat plane... http://www.strokerkits.com/custom_billet.htm Crower to call back on Monday. Geez...why cant we find someone to sell a forging prior to being twisted...sheesh...

I just wanted to jump in here...since my search seemed to overlap what was going on in this thread... 1st...I will need to contact some folks @ Eagle and se what they say regarding availablility of the flat plane crank...I seem to recall that they offered a twisted forging a while back ...and as previously mentioned...it shouldn't be too hard to get a crank "pre-twist" and go to town... 2nd...and this is something I just cam up with... ...why not use some 4340 plate that is thick enuff to cover the dimensions of the main journals...??? All you would have to do at that point is EDM the profile of the crank and have the machine shop treat it like a "very" rough casting...and then dill the holes for the lube circuit... you could just weld (build-up) any cheeks that were necessary for the slingers and shoulders..and then weld on or machine for attachment any counterweights... and I don't know if it's been mentioned already...but you can get nearly the same sound with a "correctly" designed x-pipe from about 3500+ rpm on a standard "Windsor" firing order Ford small block. My 408 does...and so does my 347. It has to be a true X and the union needs to be a football-shaped opening. My 408 sounded mean as $hit when it hit 4 grand and revved to 7,000 with that x-pipe...but it was still a potatoe-potatoe-potatoe car down low... Now off to try my luck at a flat crank...will post back if I have any luck... -David