New v-8 z-er. need help on headers, traction, & other

[Guest Night_rider_383]

Ok to start off i gonna tell you all that is might be kinda a long post so please bare with me and im sorry for the lenght of it.

 

i'm just gettin into the v-8 z's. My 1st car was a 86 300 zx, then after it blowed i went to all chevy. After getting into racing and high performance real hard core i started to look for something lighter and with better aero bodys. Plus i love the looks of the older z's body. This is when i made up my mind on a 70-73 240z. I want something this old so i can stay away from the smog bs cause the engine im building is gonna be wild.

Right now is when im gonna say this. Don't burn me when you see the hp numbers and all. One other bords i posted on i got burt cause folks couldnt understand that i have been builduing engines so lond and own a race engine shop.

 

I aint got the car yet but fixing to go look at a few. I got my engine's bottom end is done and some of the top end. I'm looking at around 850 + hp in the higher rpm range 6,500 + rpm out of this combo with still mind blowing hp/tq numbers down low

 

What i need to know is Where can i get a set of 1-7/8'' long tube headers with a 3'', 3.5'' or 4'' coll. o.d.? I have to have something like this with my engine and i am gonna need to run something like dual 3'', 3.5'', or 4'' pipes with dual 2 chamber flowmasters.

 

I know the 12 pt.cage will stiffing the chassis up some but where can i get sub-frame ties and what other mods can i do to the 240 z's uni-body/chassis to get it stiffer.

 

Rearends... I'm gonna run one of the two ways. Ford 9'' cut down to fit 31''X 18.5'' - 15'' m/t'sportsman tires on center line 15''x 15'' wide wheels with imsa type rear flares on the car. or a 75 corvette irs and cut down the lenght of the drive axles and all to fit the same tires/wheels. I aint never worked with a pro-streeter with an irs so what do i do about the ladder bars, wheelie bars, and shocks. I know with the ford 9'' soild axles i can run a coil-over spring/shock combo and weld the ladder bars and wheelie bars to the axle housing. I'm gonna run 3.73 posi gears on what ever set up i run. What do you guys think??. Also if i run the 9'' i will run strange hi-tuff axles and etc.

 

The car will run a th-400 man. valve body or 2 speed powerglide, and a 3600 rpm stall.

 

This car will see some street driving (about 3-4 k miles a year) and alot of nhra pro street class heads up drag racing.

Yes the engine will be 100% streetable, and legal for street use but only in pre 75 cars.

Also the car will have a 1 pc. tilt fiberglass front clip, a body package, 6'' l-88 scoop molded to the clip so the 6-71 blower wont stick out as far as it wouls on the flat clip.

 

What rear spoiler you guys think would be the best? Turbo whale tail, mini whale tail, or the california wing? I know i need alot of rear down force to get the tires bitting but i kinda like the looks of the cali wing but dont seem like this style will give the downforce i need.

 

Also what 1/4 e/t do yall think this beast will be running?

 

If yall are anything like me then yall we want to know then engine specs. so here goes

 

All the engine work but the block manchine work and the botton end balance was and will be done by myself

383 cid

75 chevy 350 block, race prepped, aline honed, bored and honed .030'' over to 4.030''

Callies 4340 forged 3.750'' stroke crank

Manley 4340 forged 6'' h-beam stroker rods

JE -28 cc dished forged blower pistons (yeilds a 7.992:1 c/r with my heads and thicker head gaskets,

C&A zgtf rings

Crane power-max hyd. roller cam 292/302 adv. .539''/.588 lift

pete jackson gear drive

crane gold race 1.6 ratio rollers (brings total valve lift to .575''/.627''

whole bottom end and heads arp studded

all bolts arp

dart pro 1 alum heads, 215 cc intakes, 72 cc chambers, race ported and polished by myself.

manley pro-flo 2.05''/1.60 stainless valves

k-motion springs, 10 deg. locks and titanium retainers

weiand 6-71 blower set to run 10% underdrive

dual speed demon 750 cfm carbs

msd 6-btm park box and msd dist.

plus way to much more to list

 

 

Ang again sorry for such a long post and thanks for any help yall can give me

John (nightrider)

[Mike kZ]

Hey John,

First of all welcome to HybridZ! Sounds like you have a heck of a project going. You can try Sanderson headers for what your looking for. It may be hard to clear 3 - 4" pipes though. As for the sub-frame ties you have to make your own. A few of us here have done that. With the horsepower you plan on running, I'd go with the shortened 9". I've got the same gears you want to run in my shortened 12 bolt chevy rear. Ron, here on the forum, has a BBchev 260Z that he drag races, it runs mid 8's in the 1/4. He could direct you better on a strip setup. Your engine specs sound trick, shouldn't that be a 400 block though? What hick town in GA are you in? I'm from Lilburn, Gwinnett County.

[Guest Fast Frog]

Try www.sandersonheaders.com Sanderson makes 1 7/8" headers with 3" & 3 1/2" collectors. So you're going to put a Roots type 6-71 blower engine in a Z car? This must be for a race only setup cause no idiot in his right mind is going to challange you on the street with that setup sticking out of the hood!!

[Kevin Shasteen]

quote:

---

Originally posted by Mike kZ:

...shouldn't that be a 400 block though?

---

 

His bore x stroke; 4.030 x 3.750 is the description of a 350 bored .030 & his crank's stroke is the crank of a 400.

 

4.030^2 x 3.750 x .7854 x 8 = 382.66ci

 

Kevin,

(Yea,Still an Inliner)

[Mike kZ]

Your right Kevin, wasn't thinking, that's 400 crank, not 400 block!

[fl327]

are you really sure you want to drive something that powerful everyday and everywhere?? something that beastly is bound to be big maintainance if you daily drive it, but hey, if youre ready and thats the way you gotta do it, do it man, and

give me some rubber.

[Guest Night_rider_383]

Thanks for all of the help folks. Mike kz....I'm in bremen Ga. Carroll county.

 

Fast fog... Yep a roots style 6-71 and more or less its gonna be race, but i will drive her on powertours and to cruzin's. The street racing thing done got old for me and plus no one around here will run anything i pull on the streets cause two years ago my 84 camaro blowed all the street racers off the road.

 

Fairlady 327... naw i sure wouldnt be dumb enuff to try to drive something like this eveyday. Way to much hp, to light, to much money in it to have dents caused by other cars in parking lots etc. Also this thing will just suck down blended race fuel. If im lucky maybe 4-6 mpg. My daily driver is a 1973 chevy c/10 short bed truck. With a performance built 1962 327 small journal. 453 hp and its getting to the point where feeding this one is leaving my wallet alittl on the thin side lol. 10-15 mpg it goes up and down cause my foot kinda somethimes gets on the heavy side lol

[Guest Night_rider_383]

BTW tell me what yall think on this.

I aint been up under a 240 z yet with a tape. I like to build the whole car on paper before i start into a car.

 

The way i was thinking on running the big pipes was coming off the headers, going to the trans crossmember (the crossmember that i will be useing is from a 75 vette. It has the trans mount point in the center then 2'' from the center of the trans mount on each side is a 4'' hole for exhaust pipes) well run each pipe through the holes, then stright back to about the end of the tailshaft, then turn the pipes out to the side some about a 45 deg. angle, cut the floor pan and weld two humps for the mufflers to fit then bring the pipes off the mufflers just inside of the rocker panles where they well exit in front of the rear wheels out a custom cut hole in the rear most part of the rocker panles.

 

Do yall this this will work?? And if i can ask i would also like to know what yall think the best way to fit dual 3.5'' pipes and 2 chamber flowmaster under a 240 z

 

Thanks

[Guest Anonymous]

yeah im also just gettin into this. I bought a 77 280 4 speed, engine smokes, and I ate 2 trannys! and so im buying a complete 400 SB for 25$ and im gonna re-build that and install either a th350, th400 or a powerglide, and mildly build this 400, cam, lifters, 10.5-1 compression, high rise intake, carb, hedders, and ignition, and a similar exhaust as described above, but smaller tube. and advice would be greatly appreciated, and what if I used a 350 over the 400, or should I ask how much hp would a 400 built like that, than a 350?

thanks

Jon

[Guest Night_rider_383]

Jon... Thats a great deal on a rebuildable 400 core. You really need to make sure you aint fixing to get @$#&ed over. Down here 400 sb's are real hard to find and come by. When you do find one that can be rebuilt down here it goes for around 200 bucks or better. If the 400 checks out good then i would be it for sure. If this is something your looking to drive on the streets alot kinda day to day thing. I would drop the crompression down some. One a street engine you really dont want to go over 9.5:1. The best thing i see on engines for street use is folks loves to over cam them just so they have the lope. On a 400 sb for street and maybe so strip stay under a 286 adv. cam.

 

The cams i love and seen the best numbers from it the crane power-max hyd. dual patt. cams. On the the tranny i ripped out way too many th-350's in my time. I say go th-400 of glide. Thats the two strongest auto tranny's gm built. Don't worry about horsepower man most folks dont understand this but if you got a 700 hp engine most folks well never use that hp. Worry about torque unless its gonna be a high revving drag car.

 

The 400 will make more power across the whole band over the 350, but the 350 is cheaper to build. If you work out all your plans you can build a bad ass 350. I have got over 600 hp and 650 ft. lbs of torque out of a 350 w/o anytype of power adder (blower, turbo, nos) But to go that high on all motor your getting into alot of money.

 

BTW... One big key to power is heads. PORT&POLISH i cant say that enuff.

[pparaska]

John (night_rider) that's going to be a beast! Welcome to HybridZ!

 

I know alot of people don't like the roots blower because it's inefficient, but the curb appeal is unbeatable, IMO.

 

A problem with them is seeing over them. Seems the Z is even worse about this.

 

You mentioned subframe connectors. I have plans for the ones I put in my 73 on my site under "structural mods" in the left column.

 

The problem with your idea for the exhaust is that where the mufflers and tail pipes will be will be right where the subframe connector is. The Z is low, and the seat must be low in the car, so there's no room to do both. Options are run subframe connectors in the rockers, or run exhaust in the rockers. Custom side pipes in the rockers is an old topic you may want to use the search function here to find and read up on. I'd opt for runing some big stiff tubing in the rocker boxes and tieing it in to the rear suspension you'll build and the front engine rails. JMO.

 

Keep us informed, sounds like a great fun project!

[Guest Night_rider_383]

pparaska... Thanks bud. You turned me on to something thats for sure. I wasnt thinhging about running tube braces in the rockers. This sounds like a great way to do it.

 

I'm glad to be a part of hybridZ. This aint like most of the fourms out here on the net. When i post on here i get help and so far no ones been a smart ass like on the other sites. lol.

 

The main reason i love the roots 6-71 and 8-71 blowers is cause you might say im from the "old school" of hot rodding. I got into rodder young real young and the folks that showed me the ropes was old gasser type racers and guys that was into it back in the glory days of hot rods 50's-70's. Plus think about this man whats cooler than a big chrome huffer sticking out the hood with dual tricked out holley or demon carbs sittin on top of it.

 

To tell yall the truth i would get lost on an EFI engine lol. Now on a carbed on i can built some wild stuff. To me it just seems like the EFI stuff takes away from what we all found out that makes power. Like timing, jets, spark, air fuel mix etc. With an efi engine you really dont have much say in what all the small power building tunnine stages you can go through cause the computer sets it all for you to what it was programed for. Now this is just my out look on it not to take away from anyones powerplant.

 

I hope i can get this rod to go as low as i want in the 1/4. I know shes gonna be fun to drive no matter what and ill keep yall up to date on "wild-thing"

[Modern Motorsports Ltd]

quote

To me it just seems like the EFI stuff takes away from what we all found out that makes power. Like timing, jets, spark, air fuel mix etc. With an efi engine you really dont have much say in what all the small power building tunnine stages you can go through cause the computer sets it all for you to what it was programed for. Now this is just my out look on it not to take away from anyones powerplant.

 

no offense taken/OE unaltered EFI on non OE powerplants is as you say. But adjustable EFI allows all you say and more as we're not limited to jet sizes/mechanical spark curves etc etc. MOST efi discussed here is fully adjustable. Roots blowers used to really rock when they were so cheap but lately price increases are really cutting into their old 'common/easy power' image regardless of their efficiency.

 

Ross, soon to be fuel infected

[BLKMGK]

A Roots motor can make serious power, there was a V8 monza around here with the baby Roots on it that rocked! Fuel injecting one of these wouldn't ba ANY harder than it would any other and probably easier to be honest. Roots blowers need fuel through them to cool and to lubricate - you'd just need a "spraybar" kind of deal to batch fire the fuel in the top of the blower! How some of these blower makers like BDS get away with selling their EFI for so much is beyond me. I just don't like the Roots as much because of packaging and intake temp issues but iot can't be beat for low end grunt. It doesn't need to spin up - it makes boost NOW

[Guest Anonymous]

I'm not sure I agree with the roots blowers being more expensive. Granted, its a small blower, but Jegs has the Holley 144 for like $999.99. I'll admit I was damned tempted specially on my low compression stocker. Even the 6-71's are considerably cheaper than the turbo based centrifugal Vortech's and ATI's etc. Now obviously the centrifugals are more efficient, but to be honest, if I were going to have a blower that added power with RPM instead of down low, I'd just go turbo, it has all the same benefits and doesn't use crank hp to drive it. Of course if your talking about EFI with a roots blower, then by all means your probably correct, it would require throttle bodies, bungs welded on the manifold, injectors, fuel rails and of course the electronics.

 

 

My .02,

 

Lone

 

[ May 13, 2001: Message edited by: lonehdrider ]

[Guest Night_rider_383]

EFI is a good thing for someone that wants/likes and needs it. They can make alot of power thats for sure. Just with me its like i said i'm kinda old school. I like useing somewhat of the old 60's and 70's builds but updating them some with better cams, heads, carbs, etc. If you really sit down and add it up on a blower motor the roots style is the "best bang for the bucks"

 

You can build a 600 hp (before the blower is added) roller 355 pretty cheap. trw/speed pro blower pistons $312, scat 4340 crank $600-700, 4340 rods $300-500, Good set of alum heads $1100-1300, hyd. roller valvetrain lets round it off and say $1000 for all of the valve train, Two edelbrock 1405 600 cfm carbs with a tunning kit, better fuel pump, and 1/2'' lines $600, High performance dist set up lets say $300, Plus rings, bearings, machine work, etc etc lets say $800. Now your blower a weiand 6-71 $2100, Carb linkage and other stuff to put on the blower $175

 

Running this set up with weiand's street 12%underdrive (7.0-7.5 lbs of boost) Your looking at a combo thats gonna give you over 775 hp (im saying this low number cause i dont wanna go out on a limb. If the ring gaps is set right, Good race type port work on the heads, Good machine work, Right plugs and gap, Right timming, etc You could see 850+ hp easy out of this and still be 100% streetable (in no-smog cars only) and drive this thing every day and any where you wanna go

 

Total price around $7,287--$7,887

 

Now i want all of you to know I AINT TRYING TO GET A WAR STARTED. Just showing my point. When it comes down to it i guess its all about what you yourself likes, and wants. In the hotrod world onlything that matters is that you like it and it runs good. Again im not taking away from EFI or anybody that runs EFI. I seen some fast ones out there. Its just myself i like the older style. 4 bbl carbs, old weber v-8 stacks like what was on the 283, and 327 FI vettes, roots blowers, etc. Now on the aftermarket parts im not 100% the same way like with cams. I dont want a soild cam that had to have over 300 deg. dur. to get .450'' lift, Or point dist. I'll take a hei dist. or msd set up, and a cam that has alot more lift for the deg. dur. with dual patt. lobes

 

Just my 2 cents on it.

John (nightrider)

[fl327]

i like old school too, i love the idea of a z

with dual quads and a blower sticking out the hood, nothing like pure muscle!!!!

but i do love me some efi, my next motor will probably be an lt-1 with a tremec t-5 or a t-56 with a little go-fast, not a whole lot of go-fast, but a daily driver with some muscles. but yes, there is nothing like a big gnarly v8 powered car that rumbles and has that machismo. its one of my joys in life.