Thread: 69 chevelle pro street project

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I am looking to build a pro street, and or sportsman chevelle. I want to build the chassis for 8.5 and slower 1/4 mile, I plan on putting an LS twin turbo BBC in it. I have never modified a frame or built for racing before.

I am looking for suggestions on: Tire size, gear ratio, suspension recommendations, ladder bar or 4 link?

Any ideas will be greatly appreciated and considered

Thanks!!!

I would decide just what you want to build. Will it be used as a weekend warrior with trips down the track as well as going to a cruise? Also if you have never done any frame modifications, then I highly recommend getting someone reputable to do the work. You do not want to have a car capable of 150mph+ with someone who has no idea what they are doing let alone welding.

Check out sites like racingjunk, you can buy a rig already done a lot cheaper than you can build it!

Yes, if any frame work needs done it will go to a speed shop. But it will be used for the track primarily, I will also want to be able to drive it on the street. I have been researching tubochargers and you can crank a lot of numbers out with turbo's and still keep a car driveable.

First off, welcome to CHR! I just wanted to let you know up front that you're talking a mega-buck project, especially if you're going to have to hire the chassis work done. Quite easy to get $15K +++ wrapped up in just the chassis by the time it's a roller. I suppose you're thinking an LS engine? With EFI, the rest of the electronics package, a short block stout enough to stand up to twin turbo's and heads with enough capacity to make it all work going to be a $20K +++ engine and electronics package!!!!!

Are you considering a full tube chassis or just a back half on the Chevelle frame? Places like S&W race cars offer both back half and full frame packages for the car, saves a lot of engineering and tube bending time! As Mike mentioned, lots of good roller's for sale on Racing Junk at less then half of what it takes to build one. With a bit of searching you can find the right car that's already certified, too!

If you have really deep pockets, it will be a fun car..... Just didn't want to see you start on it thinking you could get the car done and going fast for any reasonable amount of money!!!!!!

Tyler, welcome to CHR! All three of the guys are giving you good advice based on a lot of experience. Spending a sponsor's dollars is one thing, but taking on a scratch build that's done to meet certification is not going to be cheap, especially if you expect to be competitive! The old speed shop sign has been repeated in about every area of motor sports and remains very true today:

Speed costs money. How fast do you want to go??

Start with the rule book on what you need for the speed range certification----------many items have a time limit such as belts, harnesses, parachutes,bell housings, etc---------


If your looking at 8.50 area, you should look at 4 link because ladder bars are too limited and bind too much------

Thank you Dave, Yes I plan plan on building an LS motor and I am well aware of the potential costs of building a car like this. As far as chassis building, the main thing that I am concerned with is any frame modifications. I do know a few people that would help adjusting ladder bars or a 4 link depending on what I use but any welding on the frame will be done by a speed shop.

I was kinda hoping I can use the factory box frame with a back half. I have seen a few complete back half kits with all suspension included, I am just trying to figure out what combination of parts and pieces to use.

Welcome to CHR, Tyler -

Sounds like the pros above have already covered the one major factor, i.e., you need a very big bucket of money. When I first saw your post I ball parked $35-50K without bating an eye. I laud your enthusiasm and wish you well in this project. Listen to Jerry - he's built a lot of very fast and always competitive cars over his career. His expertise is legendary. If Pat McCarthy chimes in on motor build you'll be doubly blessed as he's built ton's of big blocks and knows how to not only make them go fast but last a long time as well.

The one thing that's hard to quantify is your desire to see the project through to completion. Time and hard work need to coordinate with smart decisions - knowing what you can do and what's best to have done.

Good luck and keep us informed as the project develops! We love to see a plan come together and will be your cheer leading squad.

Regards,
Glenn

I am just finishing up a c10 restomod that I've dropped nearly 35k into and that was a frame off. Most of the parts used in that restoration were primarily stock parts or just an upgraded version, (tubular control arms, drum to disc conversion etc) and SBC making 481 hp and 496 ft lbs. at the flywheel. point is I have never had to worry about building a car that will be inspected for speed as well as safety.

All I am trying to figure out are suggestions and recommendations on building the chassis specifically. I just wanted to know what works for people running at high 8's and low 9's. I am not really focusing on a motor at this time but I have an idea of how much power I want to shoot for I want to start from the ground and build up.

My first idea was back half, fab 9 inch with 4:11 gears, double adjustable coil overs, 4 link for the rear

You will probably need to run a more stout rear gear.....more like 4:88 or 5:13..........for HP you are looking at the 600-700 range I would think to run 9's.

even with an LS twin turbo? I can see being in the low 1000's for hp. Would a steeper gear work better for that much power and top end speed? 8-9 sec 1/4 car should do 140+

Rule book or you won't get on the track---------------------


Keep it light weight----------to do this in a vehicle that starts out as a production vehicle-----------will take some effort as not only do you need to handle the acceleration but carry the weight---------you will probably need to set the engine back some--probably behind the spindles-------firewall/floorboards--------to run 8s, you will need some tires-----so most likely a welded rear chassis kit with 4 links and coil overs to graph in would be a starting point plus a fabbed front section to mount engine/trans giving room to service package and suspension/cooling---rear wheel tubs

I was thinking fiberglass front clip and doors, and aluminum floor. what size of tire and gear ratio would be recommended?

And I assume QA1 coil overs are the recommended

Who would you go through looking for a front section?


Thank you soo much, I am more or less just getting ideas and researching right now but I wanted to know how others do it and what was successful for them

I really need to get that sign haha

Originally Posted by rspears

Tyler, welcome to CHR! All three of the guys are giving you good advice based on a lot of experience. Spending a sponsor's dollars is one thing, but taking on a scratch build that's done to meet certification is not going to be cheap, especially if you expect to be competitive! The old speed shop sign has been repeated in about every area of motor sports and remains very true today: