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Considering a new chassis, weight savings?

Posted By: gregsdart

Considering a new chassis, weight savings? - 08/31/12 12:11 PM

My current car is as stout as about any chassis out there, but it is a real pig that weighs 2750 with the following parts.
20 lb glass hood, steel doors, glass trunk lid, all aluminum interior , all lexan windows and 2x3 frame rails. I have stock upper and lower A arms with Wilwood brakes front and back Ladder bars in the back. I am running a Megablock 528 cube motor with torqueflite and a Dana 60 rear that is 47 inches wide at the mounting surface. 4 gallon fuel cell, single terminator injection.
Any Ideas as to how much weight I could save by building a new chassis with the same ladder bars and a strut front? It would be mild steel most likely.
Posted By: JERICOGTX

Re: Considering a new chassis, weight savings? - 08/31/12 12:16 PM

Greg, if you are going to build a new chassis, why not 4 link the car at the same time?
Posted By: rickstershemi

Re: Considering a new chassis, weight savings? - 08/31/12 12:32 PM

Quote:

Greg, if you are going to build a new chassis, why not 4 link the car at the same time?



and go moly....if your going through that much work might as well get the most weight loss as possible

Rickster
Posted By: gregsdart

Re: Considering a new chassis, weight savings? - 08/31/12 12:39 PM

My reason for sticking with ladder bars and MS is budget. I can notch and weld MS but not moly, and the entire 4 link package is what, another $800 with brackets?
I do have another body which may end up lighter by itself, as the old one has three coats of paint on it.
Posted By: MR_P_BODY

Re: Considering a new chassis, weight savings? - 08/31/12 01:14 PM

Is your 2 X 3 .125 wall or .090.... the struts will
take a fair bit right of the front
Posted By: CMcAllister

Re: Considering a new chassis, weight savings? - 08/31/12 02:23 PM

DOM MS and moly are close enough in price that it's a no brainer to use the 4130. ERW would not even be in the conversation for me. The difference is the CM has to be TIGed and we're talking about a substantial weight savings with the amount of steel needed to build a complete car. Not to mention the CM is stronger. Moly notches fine with a hole saw type notcher. Just have to replace the saw a little more often.

A 4-link would be money well spent for your application, especially if you insist on keeping the 3 speed.. It doesn't have to be the latest $$$ Pro Stock system.

With the power you are making, the new car would need to pass the appropriate SFI spec (25-4?) also.
Posted By: pittsburghracer

Re: Considering a new chassis, weight savings? - 08/31/12 03:19 PM

Quote:

My reason for sticking with ladder bars and MS is budget. I can notch and weld MS but not moly, and the entire 4 link package is what, another $800 with brackets?
I do have another body which may end up lighter by itself, as the old one has three coats of paint on it.



Greg build your car the way you want and within YOUR budget. We are not getting any younger or richer as time passes. My Daytona is mild steel, certified to 7.50, light, and a safe car. Big deal the car would be worth more down the road if its chrome moly. It will also be a lot more expensive right now. Get it done and out racing before we are all in senior citizen centers talking about how much HP HEMI"S can make on a dyno.
Posted By: gregsdart

Re: Considering a new chassis, weight savings? - 08/31/12 09:37 PM

My car is 2x3 x .125, and most all of the tube is .134x 13/4.
Depending on total cost, the thought came that I could just go aluminum block and strut front end. A heck of a lot easier and after selling the old stuff it would bring the price down some. If I could pull at least 150 lbs out of it that way, the car would run consistent 8.80s in the heat of summer, .60s in the better air. That is about as far as I want to go due to the 8.50 cert cost.
Posted By: AAR-B4

Re: Considering a new chassis, weight savings? - 08/31/12 09:45 PM

I can't answer your question about weight but I think you could save a lot of $ and effort by selling what you have and buy a rolling chassis already done and certified.
Just saying......
Posted By: rowin4

Re: Considering a new chassis, weight savings? - 08/31/12 10:20 PM

The aluminum block weighs 142 lbs. bare, but you could almost buy another car or have a c/m chassis with struts for the cost of one.
Posted By: MR_P_BODY

Re: Considering a new chassis, weight savings? - 08/31/12 10:22 PM

Quote:

My car is 2x3 x .125, and most all of the tube is .134x 13/4.
Depending on total cost, the thought came that I could just go aluminum block and strut front end. A heck of a lot easier and after selling the old stuff it would bring the price down some. If I could pull at least 150 lbs out of it that way, the car would run consistent 8.80s in the heat of summer, .60s in the better air. That is about as far as I want to go due to the 8.50 cert cost.



I just got done doing a 8 point with mild 1 3/4 X
.134... I cant believe how heavy that stuff is...
I would really look at moly... when you figure that
you buy it by weight its not all that pricey... if
I recall its 30% more cost(could be less).... I could
pick up my whole chassis in the Rampage and I guess
it was about 180# max..... BUT you have to tig it
Posted By: gregsdart

Re: Considering a new chassis, weight savings? - 08/31/12 10:27 PM

Quote:

The aluminum block weighs 142 lbs. bare, but you could almost buy another car or have a c/m chassis with struts for the cost of one.


The Dart has been my race car for thirty four years, so I am kinda fond of it, even as it is.
AS far as the block goes, I have the mega block to sell, along with a 4.15 crank to offset the cost some. I would reuse everything else. I don't know what a used Megablock is worth, but it ought to cover at least a third of the new one?
I am a KB fan, so that is what I would like to have some day.
Posted By: MR_P_BODY

Re: Considering a new chassis, weight savings? - 08/31/12 10:36 PM

Quote:

The aluminum block weighs 142 lbs. bare, but you could almost buy another car or have a c/m chassis with struts for the cost of one.



I think I payed $1200 for all the tubing in my Rampage
and $1900 for the Strange strut package(thats everything
on the front end including brakes but lacking the
rack).... so basically I have a touch over $3100
for the chassis and front end... I had a rack and
you could use your rear end... of course thats not
counting in labor welding it
Posted By: rowin4

Re: Considering a new chassis, weight savings? - 08/31/12 10:48 PM

Quote:

Quote:

The aluminum block weighs 142 lbs. bare, but you could almost buy another car or have a c/m chassis with struts for the cost of one.



I think I payed $1200 for all the tubing in my Rampage
and $1900 for the Strange strut package(thats everything
on the front end including brakes but lacking the
rack).... so basically I have a touch over $3100
for the chassis and front end... I had a rack and
you could use your rear end... of course thats not
counting in labor welding it





Still a couple thousand short
Posted By: jamesc

Re: Considering a new chassis, weight savings? - 08/31/12 10:52 PM

Quote:

DOM MS and moly are close enough in price that it's a no brainer to use the 4130. ERW would not even be in the conversation for me. The difference is the CM has to be TIGed and we're talking about a substantial weight savings with the amount of steel needed to build a complete car. Not to mention the CM is stronger.



as far as material this is my exact personal opinion. when you get down to it the majority of the expense for a chassis is labor. imho ERW is for fence posts. when i recently priced a DOM vs moly bar kit they were the same price which makes the decision pretty easy
Posted By: gregsdart

Re: Considering a new chassis, weight savings? - 08/31/12 11:08 PM

Quote:

Quote:

DOM MS and moly are close enough in price that it's a no brainer to use the 4130. ERW would not even be in the conversation for me. The difference is the CM has to be TIGed and we're talking about a substantial weight savings with the amount of steel needed to build a complete car. Not to mention the CM is stronger.



as far as material this is my exact personal opinion. when you get down to it the majority of the expense for a chassis is labor. imho ERW is for fence posts. when i recently priced a DOM vs moly bar kit they were the same price which makes the decision pretty easy


Plus there is the cost of new interior sheetmetal and the labor cost. Then paint for the chassis.
If a cage is tacked together and ready to tig, what would the labor cost roughly?
It is getting to sound like I should just shop for an aluminum B1 motor and run that. An extra 100 hp plus 100 lbs off the car= a solid three tenths.
Posted By: JERICOGTX

Re: Considering a new chassis, weight savings? - 08/31/12 11:10 PM

Greg, do you have a bender? Guys I work with buy steel in bulk, and get a little better deal that way. I can get you a price on DOM through them.

I have a bender and 1 5/8" die here.

Jeff
Posted By: jamesc

Re: Considering a new chassis, weight savings? - 08/31/12 11:34 PM

i was speaking specifically from a materials position. for your situation the engine change would probably be the least expensive, labor intensive solution to achieve your goals.
Posted By: gregsdart

Re: Considering a new chassis, weight savings? - 09/01/12 01:59 AM

Quote:

Greg, do you have a bender? Guys I work with buy steel in bulk, and get a little better deal that way. I can get you a price on DOM through them.

I have a bender and 1 5/8" die here.

Jeff


Thanks, Jeff. If I do decide on building one, I will give you a call. Sorry to hear about all the damage. Been some of that over here too. Luckily, last time out, no problems.
Posted By: tubtar

Re: Considering a new chassis, weight savings? - 09/01/12 05:15 AM

Quote:

The aluminum block weighs 142 lbs. bare, but you could almost buy another car or have a c/m chassis with struts for the cost of one.



This has been my advice to a couple other guys......funny how I am too stupid to take it myself.
There are some great deals on rollers and you could re-skin a chassis if the '65 wasn't such a strange car dimensionally.
Finding anything that would be an easy fit would be a problem.
These bodies tend to grow on a guy........not particularly aerodynamic , but they do look nice.
Off topic , but did you ever get back together with your hood mold Greg ?
I bought a hood from Showcars ( I DO NOT recommend them ) , figured I got ripped off after a year and a half of excuses and found another on a car that was being parted and bought it......only to have the Showcars hood show up two days after I took delivery of the other one.
I still wouldn't mind having a " nice " spare.
Posted By: BIGBLOCK_KAT

Re: Considering a new chassis, weight savings? - 09/01/12 11:07 AM

Greg, awhile back ...thinking about 6mo. I seen a guy in Indiana had Jimmys old
Chassis out of his '68 dart. I know different body style, just throwing it out there. oops forgot to mention it was for sale cheap and I believe c/m.
Posted By: gregsdart

Re: Considering a new chassis, weight savings? - 09/01/12 01:34 PM

Quote:

Greg, awhile back ...thinking about 6mo. I seen a guy in Indiana had Jimmys old
Chassis out of his '68 dart. I know different body style, just throwing it out there. oops forgot to mention it was for sale cheap and I believe c/m.


Any idea where it was advertised? If the early/late Darts are the same width, it might just work!
Tubtar, I did get my mold back, so we should connect and come up with a plan!
Posted By: tboomer

Re: Considering a new chassis, weight savings? - 09/01/12 01:38 PM

Greg...Did Mike Roth have Jimmys old chassis?
Posted By: BIGBLOCK_KAT

Re: Considering a new chassis, weight savings? - 09/01/12 04:42 PM

Greg,bommer...was talking with jimmy. the car was sold to roth and believe later sold but was 2x3 and mild steel chassis. sorry for any confusion.
Posted By: CMcAllister

Re: Considering a new chassis, weight savings? - 09/01/12 05:54 PM

Years ago, Herb McCandless gave me some advice, and I paraphrase -
"Money spent making the car lighter is always better spent than money spent making more horsepower; it don't break, it don't wear out and you don't have to fix it every winter."

I still believe that was good advice.
Posted By: MR_P_BODY

Re: Considering a new chassis, weight savings? - 09/01/12 07:19 PM

Quote:

Years ago, Herb McCandless gave me some advice, and I paraphrase -
"Money spent making the car lighter is always better spent than money spent making more horsepower; it don't break, it don't wear out and you don't have to fix it every winter."

I still believe that was good advice.



Very good advise.... and its easier on all the other parts
Posted By: poppaj

Re: Considering a new chassis, weight savings? - 09/01/12 08:59 PM

Guess I am a hillbilly but I would build a alloy wedge with more power. poppaj

Attached picture 7360424-b1.jpg
Posted By: gregsdart

Re: Considering a new chassis, weight savings? - 09/01/12 10:21 PM

Quote:

Guess I am a hillbilly but I would build a alloy wedge with more power. poppaj


WE think alike.
Actually it makes sense from the standpoint that I am pushing what I have as hard as a B1 motor making more power. I run a .775 lift cam, very big valve springs, and 7400 rpm in the lights. I would think a 550 cube B1 motor could easily make the 100 extra hp within those numbers. I have a very good crank, capable of going to 4.32 stroke at 2.2 rod size, which is a better deal than the 2.375 bearings anyway.
Part of the story of why this possible new chassis project came up is My grandson and myself are building a hotrod together, and I do enjoy building chassis. But it would save me a ton of time to go with the alloy block and either B1 stuff or struts.
Posted By: MR_P_BODY

Re: Considering a new chassis, weight savings? - 09/01/12 11:11 PM

Quote:

Guess I am a hillbilly but I would build a alloy wedge with more power. poppaj



Maybe .... but IF you have to play in a weight class
your sorta stuck.... but if not then why not build
a lighter chassis to start with.... I very seldom see
people go back and tear the chassis out but they also
complain that they wish the car was lighter and say
I SHOULD HAVE gone moly.... this is just what I have
seen and heard...... to each their own
Posted By: camastomcat

Re: Considering a new chassis, weight savings? - 09/01/12 11:50 PM

I think saving the 150#s and making more power is the way to go. I thought you had a B1 now. There are some out there, but what is your car certed for? If you're going high 8's now and you pick 3-5 tenths are you going to need to re-cert?
Posted By: J_BODY

Re: Considering a new chassis, weight savings? - 09/02/12 02:07 AM

Call Al and pick up either his 499 Hemi or his B1 mill. I'll be cruising up to SoDak to pick up our 360 to bring it down to AZ in about a month so I could get it that far!
Posted By: gregsdart

Re: Considering a new chassis, weight savings? - 09/02/12 03:50 AM

Right now the car is good to 8.50, but only needs a driver cage to go to the next level. The weight savings of the block alone may be worth a tenth and a half, as a number of engine builds I have known about haven't lost ANY power going to an alloy block, and some got faster. The question now is what is the strut front worth weight wise over what I have now, which isn't too heavy due to light brakes. Here is a pic of the cage as it was built.

Attached picture 7360957-Dartpics127.jpg
Posted By: camastomcat

Re: Considering a new chassis, weight savings? - 09/02/12 04:18 AM

Those megablocks are heavy. Plus a 572 B1 will make 1000 plus HP if built right.
Posted By: MR_P_BODY

Re: Considering a new chassis, weight savings? - 09/02/12 04:29 AM

Quote:

Right now the car is good to 8.50, but only needs a driver cage to go to the next level. The weight savings of the block alone may be worth a tenth and a half, as a number of engine builds I have known about haven't lost ANY power going to an alloy block, and some got faster. The question now is what is the strut front worth weight wise over what I have now, which isn't too heavy due to light brakes. Here is a pic of the cage as it was built.



A strut front end would be close to 25# off the front
Posted By: Tig

Re: Considering a new chassis, weight savings? - 09/02/12 10:12 AM

Quote:

The weight savings of the block alone may be worth a tenth and a half, as a number of engine builds I have known about haven't lost ANY power going to an alloy block, and some got faster.


FWIW we only saved around 70lb when moving from a mega blocked 528 to a KB block 572. I was convinced the scales were off and checked it on another set, we had the same 70lb difference give or take. Still it was weight off in the right place. HTH's
Posted By: gregsdart

Re: Considering a new chassis, weight savings? - 09/03/12 02:14 AM

Thanks everybody. Tig the fact that you only saved 70 lbs is an eye opener. I would have thought there was a gauranteed 100 lbs minimum.
Posted By: Tig

Re: Considering a new chassis, weight savings? - 09/03/12 06:03 PM

Quote:

Thanks everybody. Tig the fact that you only saved 70 lbs is an eye opener. I would have thought there was a gauranteed 100 lbs minimum.


Yep I was a little surprised to say the least, was expecting around 100lb too. The heavier rotating assembly is a given and extra oil pan capacity yeah, but 30lb! I'll have the mega block stripped pretty soon (the KB is already on the stand) maybe I should weigh them both
Posted By: gregsdart

Re: Considering a new chassis, weight savings? - 09/04/12 02:38 AM

Quote:

Quote:

Thanks everybody. Tig the fact that you only saved 70 lbs is an eye opener. I would have thought there was a gauranteed 100 lbs minimum.


Yep I was a little surprised to say the least, was expecting around 100lb too. The heavier rotating assembly is a given and extra oil pan capacity yeah, but 30lb! I'll have the mega block stripped pretty soon (the KB is already on the stand) maybe I should weigh them both


Tig that would be great if you weighed both, as that is the same exact swap I would like to make.
Posted By: robnbird

Re: Considering a new chassis, weight savings? - 09/04/12 03:36 AM

Quote:

My reason for sticking with ladder bars and MS is budget. I can notch and weld MS but not moly, and the entire 4 link package is what, another $800 with brackets? spend the $800. now. 1 year down the road you will say I wish I had spent that extra money.
I do have another body which may end up lighter by itself, as the old one has three coats of paint on it.

Posted By: Edge

Re: Considering a new chassis, weight savings? - 09/05/12 05:12 AM

The best advice I can offer is to set a target and stick to it. I started with the plan to go with an aluminum B1 motor because I wanted to go a little faster ( that was the first plan) from there I decided with the extra power a four link would be nice instead of the ladder bars, then it seemed to make sense to do struts and finally I ended up with a 25.1E chassis. The down side I have not raced for two years and I could have been having alot of fun with my old backhalf Duster. I even started building a more powerful engine and finally gave my head a shake and set a target and now I am sticking to it.
Posted By: gregsdart

Re: Considering a new chassis, weight savings? - 09/05/12 01:18 PM

Thanks for all the input, but I really never got the answer I was looking for. I know I put a lot of unnecessary weight into this chassis when I built it. I was hoping to get a ball park number on what I might save by going to the minimum spec tube and doing it by the rules,IE smaller tube where it is alowed, and an all round tube cage. I know Cudabin is 250 lighter than me, with very similar components. Other cars out there for comparison ought to give me enough info to make a solid decision on weather it is worth it. If I can dump 250 pounds with the selection of the right tube and some parts, like struts, then It would be worth it to me as that would get me a solid .020 gain at this level. So anyone with comparable rides, please speak up.
Posted By: MRMOPAR622

Re: Considering a new chassis, weight savings? - 09/06/12 09:58 PM

I would look at the cost going bigger on the engine vs lighter on the chassis to see which would give the best bang for the $$$. BS that's just some advice I wish I would take myself when ever I started a new project.After all the $$$ spent that is double time I finish what I plan on it being,I always end of asking myself was it worth all the $$$ and time for so little gain? And the answer is always NO,but I always made the same mistakes over & over. I know better,but the racer in me has yet to learn that,and the racer always has the say.
Good Luck with which ever you chose,if it were myself I would end up doing both!

PS This is a question only,you car runs very fast now so it must be working well do you think it will handle another 100 Horse-Power and still work well?
Posted By: 69dart

Re: Considering a new chassis, weight savings? - 09/06/12 10:58 PM

I think you would be better off selling your existing car complete and buying the car you want. I know a few guys that have re-done the chassis looking to save weight or update to next SFI Spec and they have a common theme. They wish they would have sold the existing car complete (which were all great working cars) and started over or bought a new 'to them' used roller. Alot of nice cars out there on the cheap right now.
Posted By: Tig

Re: Considering a new chassis, weight savings? - 09/29/12 05:45 PM

Quote:

Tig that would be great if you weighed both, as that is the same exact swap I would like to make.


Hi
Well I've managed to get around to weighing both of these blocks. Not an exact science as I only used an old set of bathroom scales but here are the results.
Mega block 248lb
KB block 165lb
So the difference on the scales we used was 83lbs.
Both were weighed with caps and cross bolts fitted.
The mega block was at a 4.500 bore and the KB at a 4.530 bore.
The 83lb saving was probably eaten up a little by the rotating assembly (4.5 stroke crank, 7.1 rod) and the sump used on the KB has more capacity.
HTH's
Tig
Posted By: Al_Alguire

Re: Considering a new chassis, weight savings? - 09/29/12 10:31 PM

That is a light megablock you have there. All of them I have weighed including an older ones were just under or north of 300lbs. The World blocks being the heaviest at 310ish. My KB lowdecck block was 163. Just FYI from my experiences. I hear the Indy block is even lighter, heard some crazy numbers like 125 or so.
Posted By: Tig

Re: Considering a new chassis, weight savings? - 09/30/12 11:24 AM

Now that is a big difference, could be the bathroom scales are reading light, it's all I have that will weigh something that heavy. Mega block was cast around 12 years ago, does this qualify as an early casting?
Used as a tool for comparison only, does the 85lb difference seem reasonable?
As earlier, we only saved 70lb swapping from the 528 mega block to the 572 KB. Everything else on the car was the same, barring the sump.
Posted By: Anonymous

Re: Considering a new chassis, weight savings? - 09/30/12 03:25 PM

Not to sound bad in any way, so please do not take offense, but if I was at your age I would probably ask myself how much longer I might be racing and is all the expence of trying to go two tenths faster really worth it. As mentioned above your car is fast now so unless your competing for a national tile................? A member once told me on one of my posts that I was over thinking things to much, I think he was right. JMHO so again please do not take offence.

Superfreak
Posted By: deaks

Re: Considering a new chassis, weight savings? - 09/30/12 04:40 PM

Greg
In your opening post, you said you had steel doors, surely glass doors would save a fair bit of weight and do you have lexan or glass in the car ?
Mick
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