SBC phase II advice

[grumpyvette]

if you want something that looks good sticking thru the hood....

Summit SUM-CWND401S $799

 

or if your buck$ up

$3300

http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=IN&Product_Code=NG1702&Category_Code=

[Rat Fink]

hmmmm

 

dual quads you say?

 

hmmmmm

 

I guess if it's going to be normally aspirated, at least it could be maximally aspirated...

[COZY Z COLE]

Let's clear some of the cigar smoke from this thread.... Have a read of Weiand's manual that comes with the 144 blower. I'm running 10lbs. of boost with this blower. To do so means $$$$ spent on the engine build, cooling system, ignition system, drivetrain, exhaust system, frame support, rear end, ect. Going this route is not to be taken lightly if you want equipment to last. Don't guess on this build. I've posted many threads on my initial set-up and upgrades I've done. PM me if you are serious on going the 144 blower route.

One other thing ....Comparing a roots blower to a centrifical force blower or a turbo is like comparing apples to oranges...This is also covered in the manual.

 

Here's the link...http://www.holley.com/data/Products/Technical/199R10244-1.pdf

 

In it they state to prevent detonation to have a 8.5:1 comp. ratio.

 

 

LARRY

[Rat Fink]

Thanks, I've been through this manual before, and that's one reason I think I shouldn't just bolt it on to my existing motor. Another reason is the speed shop advice. But I ask you guys because I know people who've done it

and say that I'll get away with small boost and small HP increase. On the chart, 4psi gets me to 12:1 effective CR, not too scary. Back of the envelope: 300*(4+14.7/14.7) = 380HP (I know this is very approximate). You can see some others on the thread think static CR isn't as important as I might.

 

key phrase"...if you want your equipment to last"

 

This guy is doing it at 9.6:1 nothing forged,:

http://orangecounty.craigslist.org/pts/702291974.html

 

I'm not looking for 10lbs of boost, of course you've got a lot more power to contend with. I'm also not looking to revamp everything in the drivetrain, one reason for the modest goal. I think I'll be OK going from 300 to 400 after researching this site about the R200.

 

I don't mean to give the impression I'm taking this lightly or that I'm taking wild guesses. It's a lot of $ either way I go and I've been kicking this around for months already with the resources I have.

 

Thanks for the PM offer

[Jerminator96]

Maybe I don't get it,that's not what I thought. Can you point me to an explanatory link or something?

 

I'll do my best to explain this.

 

Static compression ratio describes the amount of air compressed by the piston relative to the size of the cylinder. In other words, from bottom dead center to top dead center in a 10:1 compression motor the air in the cylinder is compressed into a space 1/10th of the total volume of the cylinder.

 

This is not taking into account the time that the valves are open. Dynamic compression ratio calculates the compression from the time that the intake valve is closed until the piston is at top dead center. While the intake valve is open the cylinder cannot build pressure, so the DCR should always be significantly lower than the SCR.

 

Now what really matters in detonation is cylinder pressure, which takes into account many factors (humidity, air temp, volumetric efficiency, rpm, etc) and it is nearly impossible to calculate accurately. Some of the serious engine builders have started to use in-cylinder pressure transducers to data log this information, but most of us don't have the money to set something like that up.

 

Read this, it probably does a better job explaining everything.

 

http://www.empirenet.com/pkelley2/DynamicCR.html

 

So we know I can do 400/400 RW with NA 383, but I couldn't do those numbers at 8.5:1, JT1 says 10.5:1, you're close at 9.5:1. And you think I'd be able to SC that later? I'm confused.

 

Why can't you make those numbers with 8.5:1 compression? I could build you a motor that makes 600hp with 8.5:1 compression, it would be expensive, but I could do it. If I can make 385rwhp with a 355 then you can make 400rwhp with a 383, and if my motor could take over 15psi and 800rwhp on pump gas then you can get that little Weiand blower to work at 9.5:1 SCR.

 

Just my $.02 though.

[grumpyvette]

other bits of useful info

 

 

http://victorylibrary.com/mopar/blower-engine5.htm

 

http://victorylibrary.com/mopar/cam-tech-c.htm

 

http://victorylibrary.com/mopar/chamber-tech-c.htm

 

http://victorylibrary.com/mopar/piston_position-c.htm

[Jerminator96]

other bits of useful info

 

 

http://victorylibrary.com/mopar/blower-engine5.htm

 

http://victorylibrary.com/mopar/cam-tech-c.htm

 

http://victorylibrary.com/mopar/chamber-tech-c.htm

 

http://victorylibrary.com/mopar/piston_position-c.htm

 

That is some great information man, especially the second and third links.

[Rat Fink]

ouch, my brain is full

[ktm]

Eric, it was great running into tonight on the road. I'll be watching what you decide to do with interest.

 

For the others, Rat Fink and I ran into each other on the road earlier tonight. A quick little exchange of horsepower display and we pulled off to the side and BS'd for close to 2 hours.

[Rat Fink]

Hey man that was fun, we gotta do more BSing, but preferably indoors, and with ethanol injection.

[HICKL]

I'm with you rat fink on the need to have something sticking out off the hood. I am currently running the dual quad tunnel ram on my 383, which is very streetable by the way. Is my dream though to have a roots style blower on top, just for the coolness factor. I love my motor, many thanks to grumpy and a few others for help with the build, but if I ever destroy it, will builld a lower compression one and put the blower on it.

 

Jeff

[Rat Fink]

Thanks Hickl.

 

I was talking to M and R in Glendale CA about an SBC 427 bottom end for about $4k. I could use my heads, get big pump gas HP, and have enough guts let over for laughing gas. (and you can bet I'd be laughing)

 

This is in the "no replacement for displacement" school of thought.

A dual-quad-nos-427 is about as cool as a blower, and with props to the Cobra, I'd call it a Zebra.

 

Try this exercise: say "427" three times. You're grinning like a maniac aren't you? Me too.

 

I know with nos I'd be spanking that rear end harder than an escort spanks a senator's, but that could be the next big upgrade project.

 

Yeah I know I'm all over the map and seem to have no idea of exactly what I want or what I'm doing, oh well, whatever it is, whenever it is, it WILL be cool.

[Jerminator96]

You want to run those heads on a 427?That doesn't sound very efficient. I guess when you get bored later you can always throw on some decent heads and swap out the rest of the top end, but I'm a 'do it once, do it right' kind of guy.

[Rat Fink]

You don't think that'll work?

I thought the heads were the best part of my existing setup.

I definitely thought they were good for the 383, about 10% up from the 350.

Then I thought it was a short stretch further, about another 10%, to the 427.

 

this is probably a really cool solution, just too much $:

http://store.summitracing.com/partdetail.asp?part=WRL%2D101006&autoview=sku

[Jerminator96]

I'd say those are great heads for a 302-327, good heads for your 350, and 'useable' for a 383...but a 427 is a bit out of their league.That being said, you do have fairly modest power goals for your 427 so if the budget is tight then it's better to have a low power 427 than a high power 350 in terms of reliability.Did you ever mention a budget? I could recommend some heads but cost is a factor.

[dr_hunt]

He's right, they are not the best choice for heads for a big inch motor. budget heads would be some cast iron large ports like the dart iron eagle 230's. The best would be AFR 215 high port eliminators if staying with 23 degree or even better would be some 18 degree or 15 degree brodix heads. It's all a function of money. Keep in mind that 400 hp in z is quite a all around package.

[Jerminator96]

The Iron Eagles would be my recommendation for a budget head also, but I am a big fan of buying used too. If you look around you can find some good deals on the nicer Dart and Brodix heads with low mileage or a fresh rebuild. The 15 degree stuff would definitely be the way to go for serious power but it would be difficult to do it cheaply. Even if you did find a good deal on the heads you still need the valvetrain, intake, custom exhaust, probably pistons, etc.If money is no object then spend $20k on a Dart Little Chief setup and you can have 1200 hp naturally aspirated.I could also check with my uncle and see if he still has an extra set of heads from his dirt track car, if they can feed a 360 at 9000 rpm they will probably do alright with a 427 at 6500. If your interested let me know and I'll get a price and the details.

[Rat Fink]

Thanks Jerminator and Hunt,

I do want aluminum heads for weight reasons.

 

I did a post in For Sale looking for interesting trades, by the way:

http://forums.hybridz.org/showthread.php?p=906638#post906638

 

Budget is kind of variable, $6k is easy, $10k is starting to get hard to explain to my wife, but ... Forgiveness is a lot easier than permission (Patton?)

 

Yeah I don't really want 1200HP anyway, I still wanted to keep the R200 LSD and ZX half shafts for a while and don't want to do all the frame stiffening required to keep the doors from popping open when I hit the gas.

 

Where do you look for this stuff used? I've been on eBay, Craigslist, and of course HybridZ but I don't know anyplace else.

[Jerminator96]

Racingjunk, it can be a real mess as far as searching for something but if you have patience you can find great deals.$10k can put together a heck of a motor, even after spending $4k on your shortblock, especially if you get the heads and intake used.

[Rat Fink]

oh yeah thanks I got there indirectly a few times by googling various terms.

I'll try going in through the front door.

 

I'm in SoCal, so there should be some stuff local, but probably not like AZ where you can drive your nitro funny car to the 7-11 to pick up new slicks.