Wayne has a T-350 in his with a killer motor that he walks out on the little 70 series bias ply tires. I don't think he has anything super killer under there, but I'm not dead sure. He comes around here occasionally and has always been willing to share info.

I got by with stock stuff into the low 11's and high 10's,,but I was launching real easy with the 427 in it on slicks. I never had issues with center sections (which I built..but it was nothing really special) but I broke several outer stub axles and one halfshaft. Got tired of that so in went the Dana 60 IRS!

Heavy as heck...but I went to the track again last night and had lots of comments on how cool it was to air under the front tires on the 1-2 shift! And it's all in one piece still..so that's good!


JIM

 

In the class that Wayne ran in it would be difficult to hide something like this.

I don't know for sure if it was the stock differential but like I said above it will be kind of tough to hide something like that. What difference does street tires make? The car ran a 10.59. To the best of my knowledge this is still the ET record for the F.A.S.T. class.

Driving slicks is easy. Getting seven inch bias ply street tires off the line takes a driver and a perfect suspension setup. Wayne's car comes off the line like a rocket.

BigBlockk

Later.....

 

Street tires make all the difference in the world.. If there's too much shock on street tires, they spin.. It's SHOCK (in combination with traction) that kills rear ends and not horsepower. Sure, you can install a 1000 HP engine on 215/70R15 tires and you won't break anything as the tires will spin before breaking anything. Traction is the #1 cause for rear end failure. Sure, with enough horsepower and street tires, you can run very fast without breaking stuff BUT you'll need a TON more horsepower to get the same ET's.. A 550 HP engine is a lot cheaper than a 700 HP engine etc... I ran mid 11's with only 465 HP (365 RWHP) because I ran slicks and got 60' times in the 1.5x range. That's why my rear ends didn't last too long.. I've seen as fast as 1.43 60' times with the stock differential with AUTOMATIC cars but I haven't seen a differential that held up for more than 50 runs with 60' times like that.

 

For anyone who would like to read about Wayne's car. This thing ran a 1.61 sec. 60' time on G70 bias ply street tires. Amazing.

http://www.fastraces.org/fastraces/f...7!OpenDocument

BigBlockk

Later.....

 

1.61 is amazing on those tires... I usually got 1.8x on street tires with my '68 but not anywhere close to that.. However, he does have a TH350 which makes launching easier than with a stick car... The automatic really helps to prevent breakage.. I'm curious if he uses Tom's stuff or not???

 

well... I am knocking on the DOOR to 11's with my 77'

I am running a carbed 346 ls1 with TH350 (3000 stall) 3.36 gears 275/60R15 drag radials (stock rear with suspension mods)

224 comp cam RPM air gap intake... with C5 manifolds (no headers)

currently running 12.3 @111

I have a cheater plate system to go on it jetting at 175..but will probably start at 125 or 100 shot... that should get me 11.5 to 11.30s

I want to add a set of AFR heads or something close in performance for less money... that give easy 40rwhp... so I plan to run high 10's with the heads and No2 shot.

hopefull bout 11.7 on motor and 10.9 on the gas...

with a new set of drag radials... MINE ARE TOAST !!!

bye bye Z06

 

That's some killer ET for having relatively-tall 3.36 gears behind a rev-happy LS1:
I'm guessing you trap about 5200 RPM @ 111 MPH?


To run 10s on giggle-gas, I suspect you'll need to turn 120+ MPH, and if you run a 27"-tall rear-tire (a guess?), 3.90:1 gears would put you at just-over 121 MPH at 6500 RPM:
to run 11.70s, your trap-speed would be about 113 MPH, and the 3.90s would turn about 6050 RPM.

 

Tire is 28inch tall... bfg drag radial 275/60r15

as far as the trap... it seems I am shifting into third about 75-100 yard away from the light... maybe about 3500-4500 going into the trap.

gears would be nice... I wanna put the kit on first to see how the traction is.

 

what usually breaks in the rear? how does it happen also? i got 3" half shafts, HD spline inner axles, 373 gears made by strange, and dragvette 6-link. never see slicks. thanks

 

There are lots of weak parts in stock rear ends:

I mostly had issues with the posi case which would crack...
The axles are only 17 spline and they aren't too strong either.
Stock half shafts tend to twist with high horsepower and slicks
stock u-joints break easily but if replaced with solid 1350 spicers, they hold up to up to 650 HP..
If you won't run slicks or at the drag strip at all, you shouldn't have any issues. Even with street tires, you might break down at the track as a well prepped track will give you a lot of traction - even with street tires.

 

I have been reading this thread and many good points have been brought up. There are always the rare few that have not had issues with breaking things but mostly from what I have ssen and been through a decent amount of horse power (450-500) a stick and decent traction killes the stock rears. I do not know what kind of power my car makes, I estimate close to 500 off the laughing gas.... my car weigns in at roughly 2600 pounds. That combo would be plenty powerful to get me in the mid to low 11's but I have not even made it to the track because I am breaking the car on the street I run a set of 325/50/15 Mikey T drag radials and a 3k launch on the street is destroying spindels, I have been through two already. It is the initail shock and then traction as Grand sport mentioned. If I had an automatic I am sure the rear would hold up and I could get the car in the 11's and 10's on the gas.

It pretty much comes down to your combo and how deep your pockest are, as mentioned you can go very fast with les hp and lots of traction. But at the same time you can achieve good times with less traction but huge hp to make up for it on the big end.

For anybody out there who wants to drag their car ask youself this:
How fast do I want to go?
How much money do I have?
Am I prepared/able to fix the car when it breaks? Notice I said when and not if...LOL

 

My plan at this point is to buy a 69-72 and put a new BB in it, plus whatever else I need to make everything work/run reliably. I'd like to have a low 12's car, though I'm sure that's pretty weak for you guys, I think that's enough for me on the street. I doubt I'll get into drag racing at the track or anything like that, but I'm sure I'll make it there once or twice...mostly I'm looking for a fast car I can have fun elsewhere. After reading this thread, I'm wondering what type of BB/transmission combo I need. For only being in the low 12's and NEVER on slicks, will a stock rear end hold up? I don't want to do something that's going to cause me pain down the road; I'd like to do everything right the first time so I can enjoy my car and not have it in the shop all the time. I'm looking for any and all recommendations on what needs to be done to make a 69-72 BB car run in the low 12's. Thanks guys.

 

Well first off a low 12 quarter with a BB vette is pretty easy IMHO If you are starting from scratch make sure you build a solid bottom end do not skimp here. For a street car I would suggest 9.5 or a 10.1:1 piston to make really good power and still run on pump gas. If you pocket allows you a good set of aluminum heads and a roller cam would be nice but a flat tappet will do just as well. Do your home work on the combo if you build a mild big block you will have 450-500 hp which is plenty to see a 12.30 or better without slicks but a decent street tire.

As fas as a trans I prefer a stick because of the fun factor and if you run a street tire that will spin you should not have a rear end problem if your under 500 horse or so. An auto will help you get the car down the track without being so hard on the rear but if you do not intend on being at the track much then just ask yourself what is more fun on the street.

What you are wanting is a pretty attainable thing IMO, BB are great I wish I had one A decent combo will net you plenty of HP to be happy with on the street.....There is no replacement for displacement

 

Amelio, thanks for the reply. My plan is to buy an already made engine (either GM crate or maybe one made by an independent shop) and bolt it to a manual tranny (as you said, I've just got to have a manual!). I want to run pump gas and use normal street tires. It won't be a track car, but I also don't want to worry about stuff breaking when I feel like "getting on it" out on the street. It's not like I'm going to drive it hard like a 16 yr old who just got his license (been there, done that), but I'd be lying if I said I wasn't going to open it up sometimes.

What would you recommend for an engine/tranny combo (as in manufacturer, types...especially the tranny)? There's a decent possibility I'll buy a SB and then do an engine swap, so I'll probably just install a new tranny while I'm at it...I don't want to use a tranny meant for a SB.

If getting a new rear end is the best way to go, what are recommendations? I've read about 12-bolts, but what manufacter is good/what prices am I looking at? I basically have around a 10-12K budget for all my parts (excludes the cost of the car). So I need the engine, tranny, rearend (if required) and other accessories to be w/in that. Is it doable?

Last question (for now): I read some performance stats a few weeks ago that had a stock '69 w/ a 427/435 HP doing 0-60 in 6.8, but a '70 w/ a 454/390 HP doing the same in 5.7. Why the big difference w/ 45 less HP? Basically that says to me the HP # doesn't mean everything...so just b/c I buy a 450 HP engine doesn't mean I'm getting a 12.xx sec car. How do I know which engine is going to give me the best result?

 

I would not spend my money on a 12 bolt for a street car with street tires... even if I had a big-block.

as far as the factory 427 vs 390 horse 454... it is the heads and compression ratio.

435/427 was the big boy engine from 1967-1969... al. heads High compression solid cam.

You not going to get 427/435 factory motor unless you want to spent way more cash than a GM CRATE engine!!

You want... A hi-po GM crate motor like the ZZ502/502hp it is pump gas friendly and should get you low 12s...spinning your tires down the track as you row through the gears... (spin'n aint win'nn) but it SURE is Fun !!

Oh... BTW ... look at getting yourself a T56 tranny from a 94-96 LT1 F-body it will bolt to a BBC (I would avoid a 93 T56...better gears but not as strong) Having the (2) OD is nice on the street and Highway...

 

I agree a T-56 would be a great choice for the street, I would alos no bother with a rear end as that alone will eat up about $5k. If you are looking at a crate engine I would definitely go with a ZZ502 it is ready to go. If you are working with $10-$12k you're engine and trans is going to eat up close to $10k I believe the 502 is right at $8,500 and change from summit and you can pick up a good used T-56. With those two purchases you should be left with a few dollares for a clutch assembly and some odds and ends.

The stock rear should be fine if it is in good shape, I personally love a stick in a vette for a street car. To me it does not get much better than banging 2nd and counter streeing

That 502 with a T-56 and a decent set of street tires should put that car in the high to mid 12's with traction issues As I mentioned it is hard to beat a big block.....I hope to have a mountain motor in my car one day a 565ci or so

Let us know what you get

 

What about an engine similar to this:454
Either that or 502 HO

Maybe the top one is a little more power than I want (more just b/c I don't want to break rearends), but I'm sure I could call him and specify the HP/Torque I'm looking for. What are your thoughts on those two? Both provide a 1 yr warranty, so that's not really a factor (too much anyways).

Also, I was looking at the TKO-600 from this website: TKO-600 Profit System. I really would like to put a 5 speed in to give me better economy/cruising ability when on the highway. Does anyone know about these guys? Good buy?

Thanks a ton for all the help guys, I appreciate it!

 

Why not go to the source of where this kit is made instead of a reseller? Look Here. http://www.classicchevy5speed.com/

 

Good call, I'll do that. Thanks!

 

Speed gets expensive, huh!
I talked with you last year sa we passed thru Lufkin headed to Bowling Green for the CF Cruise-In. Load up and go with us this year.
-Patrick