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77 Rear-end / Hp ?

C

crebo

Guest
Hello fellas,

I will finally get my car back tommorrow. 77 stingray. I've swapped engines. Went to a 402 BB, 427 heads, heidman headers, msd ingintion/distributor....700r4 tranny (beefed up) by bow-tie transmissionshere in Hesperia, Ca. 2 1-2 inch exhaust all the way back to flow masters. Oh yeah 800 cfm Holley.

Anywayz---wondering about how much rwhp I'll be looking at?Maybe somewone with a similar set can let me know.

Question...My mechanic is saying that I'll need to strengthen the rear-end.....lock it down. Saying it will be tough for the stock rear end to handle the new found torque. Basically telling me that I'll tear the ass-end out of it when I really get on it. Sounds like fun actually....but would rather do a little preventative maintance if possible.

I would love any suggestions on how to make that happen. Remember I play very good golf but car smart I'm not. So please put it in layman's terms.

Again Thanks to all
 
7

73BB

Guest
What is your compression ratio?
Is the Holley a double pumper? (I believe the 800 is)
Which cam are you running? (hydraulic/solid/roller etc)

Answering these questions will make for a better estimate.

The rear-end is definately the weakest link. At the very least replace any old u-joints (drive-shaft included). Use the ones that DO NOT have grease fittings.

Sounds like a lot of fun!

Good luck
 

Tom73

Well-known member
Joined
Aug 21, 2001
Messages
1,427
Location
Round Rock, TX
Corvette
73 LS4 Coupe - 04 CE Conv
crebo said:
Question...My mechanic is saying that I'll need to strengthen the rear-end.....lock it down. Saying it will be tough for the stock rear end to handle the new found torque. Basically telling me that I'll tear the ass-end out of it when I really get on it. Sounds like fun actually....but would rather do a little preventative maintance if possible.
That is the same rear that was used behine the 427's and 454's including the L88 and ZL1. For street use should be okay. Just upgrade the u-joints to the ones using caps in place of the U-bolt ones. Now if you are running 600 ft lbs torque with 12" drag slicks and side stepping the clutch at 6000 rpm, then you will have a problem. :)

tom...
 
C

crebo

Guest
73BB

Hey thanks,
You're right about the carb. Compression should be 10 to 1.
and the cam is mild 270.

Thanks for the advice.
Ashman
 

AKRAY4PLAY

Well-known member
Joined
Oct 14, 2001
Messages
584
Location
Wasilla, Alaska, U.S.A.
Corvette
'77 L-82, black on black. Full mod 406 small block
Crebo,
try running your engine specs through Desk Top Dyno. it is a computer program that gets very close to real world numbers at the crank. you will need to enter every thing about your engine, cam specs, rod length, stroke, head type, valve type, intake runner size, etc. the program was only off ten hp and 12 ft/lbs from the dyno runs i made.
as for the rear end, i've been running stock all summer and not had a problem. that doesn't mean something won't break though. as for your u-joints, i would definately run Dana Spicer, they test the toughest. as for the grease zerk vs. no zerk, 4 Wheel Drive magazine did a very extensive test on u-joints. they found that there was no real difference in breaking strength between zerk/no zerk u-joint tests. the joints just broke in different locations, body on one and pin on the other. they recommend running greasable joints just because you can flush water and dirt out when lubing, and they last longer if maintained. i am running greasable ones in mine, and they are holding up fine to some hard abuse.
i would not worry right away about your rear end. just make sure everything is tight in the drive train and enjoy it! you will be taking it easy breaking it in anyway. she will let you know if something is wrong before you start romping the throttle in a couple hundred miles. brian
 
C

crebo

Guest
AKRAY4PLAY,

Dude it is def. nice hearing from you. The video that you have is the bomb. Anyway...I'm sure that I won't have the hp and tq that you have. So I shouldn't have any rear end problems....knock on wood.:hb
So that really helps alot. I was hearing that I'll lose a little hp due to the automatic 700r4. I'll never know. I need alittle more personal info on my spec and I'll run it through desk top dyno.

Question: Do you have any traction bars or anything sticking your car to the ground? Sorry if I missed it in your list of mod's. You really have a nice set-up (standard setter) :BOW I love the car's profile

Anyway thanks much and I'll keep everyone posted...
 

AKRAY4PLAY

Well-known member
Joined
Oct 14, 2001
Messages
584
Location
Wasilla, Alaska, U.S.A.
Corvette
'77 L-82, black on black. Full mod 406 small block
Crebo,
Thanks for the nice words, but i don't think i am a standard to measure from. if anyone is measuring themselves against me, i hope you all surpass me by far. as for the car, the rear end (as well as the front) is equipped with the vette brakes performance plus package, cost $2000.00. it is their top of the line kit for the c3's. the strut rod kit was the best dollar per performance for the traction factor. it is part of the whole kit, or can be purchased seperately for $200-$300. i ran mine with the complete stock set up, and the camber would not even think about holding still. i would reset the camber and crank the **** out of the lock bolts, but as soon as i hit the throttle it looked like a neglected car with the classic c3 tire lean. yours will do the same without the kit. you may not have the same hp numbers that i have, but don't underestimate the torque that a big block can generate even with a mild cam. the extra stroke a bb has makes a bunch of difference in the torque figures. torque is what will break parts or make your car scoot. i would recommend buying the whole suspension kit since you are running big block, but if you are on a budget at least buy the strut rod kit, it will pay for itself in tires alone if you drive anything like i do. enjoy that bad boy and remember bf goodrich radial ta's are only $80 a copy!! smoke 'em if you got 'em, brian
 
C

crebo

Guest
AKRAY4PLAY,

Car wasn't ready today. Had to take to a trans shop to make the final adjustments to the 700r4.(Warranty thing) Plus they broke my A/C dryer.
The car really sounds cool though--strong.
I'm on a pretty tight budjet just as you said but still gonna look into strut rod kit. Pretty sure that I'll need to work on my suspension some. I already have bb springs and shocks. I just have enough to keep rollin for now.
Anywayz !!!!!!I still have a few eyesores.....My fan shroud is pooh-pooh. I guess I'll have to buy another and make more precise cuts. Do you have any ideas?
I'm still not satisified with my valve covers. I really wanted to go with tall but Brake boost....A/C equipment won't allow. :mad
Just eyecatchers.....
Thanks again for all the advice......Hopefully I can talk my wife into letting me buy a dig camera.

Ashman
 

AKRAY4PLAY

Well-known member
Joined
Oct 14, 2001
Messages
584
Location
Wasilla, Alaska, U.S.A.
Corvette
'77 L-82, black on black. Full mod 406 small block
as far as the fan shroud goes, try swap meets or junk yards. i think that an original equipped bb vette from '73 or '74 is a direct bolt in replacement. it may be so for eariler years as well ('68 to '74), not sure but maybe someone else can chime in with the answer. as for the valve covers, the brake booster is tight! gm performance sells some sharp looking cast aluminum covers with baffles for around $100. i would highly recommend using baffled rocker covers. they don't ingest, or better digest, oil like non-baffled covers. the only time you should run without baffles is when you have to have a rocker arm girdle to keep your valve lash from coming undone. that usually only becomes a problem when you run .700" lift or more on the cam. as for the camera thing, most photo shops will digitize your photos and put them on floppy disk for pretty reasonable rates. only a few hundred more dollars and it's done!! until the next little upgrade! i would not worry about the little things just yet. get it running good then polish her up.
 
C

crebo

Guest
Another question ref. fan shroud. Since I will be buying another shround. Should I look for one like the BB. or one that covers most of the fan?
Which will be better for cooling?
 

AKRAY4PLAY

Well-known member
Joined
Oct 14, 2001
Messages
584
Location
Wasilla, Alaska, U.S.A.
Corvette
'77 L-82, black on black. Full mod 406 small block
i would look at the bb set up. it should bolt right in and look great. you need a little clearance between the fan and shroud, but that should already be incorperated in the bb shroud. i believe the fan blades (diameter) are the same for the sb and bb. some years came with five blade fans and others had seven blades. yours should have seven, and that is what i am running.
 
C

crebo

Guest
427SB
Thanks...It looks like the kit AKRAY4PLAY was recommending.
Anyways still don't have my car. Will be ready soon. Had to drop it off at Bow-tie transmissions for a final adjustment.
Ashman
 

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