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Author Topic:   Moving motor Back
ss38k
Dirt Full Roller

Total posts: 61
posted January 06, 2003 12:06 AM
hello every one .can anyone tell me if moveing the motor back 3 to 4 inche's is worth all the work. of lineing everything back up. and moving bracket's drive shaft and so on. most guys tell me it will help with forward bite .what kind of gain's have you guy's seen. i could use soom forward bite.and some rear % is only around 50.5 thank's

racer17j
Dirt Forum Champ
Total posts: 1565
posted January 06, 2003 01:01 AM UIN: 54865418
the farther back the better off you will be just make sure your rules don't say anything about it and depending on the body you run if you can't do anything to the fire wall it's gonna be hard getting a whole lot of set back out of it

ss38k
Dirt Full Roller

Total posts: 61
posted January 06, 2003 07:04 AM
hello racer17. i can move the motor back to 1# plug. and i can move the fire wall .i just have to remount it.but will my car handle that much better.thank you


racer17j
Dirt Forum Champ
Total posts: 1565
posted January 06, 2003 10:23 AM UIN: 54865418
yes there is an advantage thats why they move to motor so far back in a modified.to get better %'s the more weight you can get in between the wheels the better you are the farther past the wheels the more effect weight has so it's alway best to have heavy stuff in between the wheels if posible

ss38k
Dirt Full Roller

Total posts: 61
posted January 06, 2003 09:54 PM
thanks racer17 for the info. is there any chance that i could gain 2or 3 percent by moveing the motor back 3 to 4 inche's. or not that much .again i am just trying to see if all the work that has to be done is worth it. thanks again


ss38k
Dirt Full Roller

Total posts: 61
posted January 08, 2003 11:46 AM
dose anyone else have any info on motor placement. besides racer17. like to here more in put. thank you all. RACE ON

DEEDDUDE
Dirt Maniac

Total posts: 111
posted January 08, 2003 05:49 PM
ss38k, sounds like you have access to scales. Put the car on scales, put 100lbs of ballast at your pedals, look at scales, then move it four inches. Not a very big difference, now multiply that by four, still not a big difference. It's a lot of work for a small gain. You will add less than a 1/2% in rear weight by moving the engine back. I've put over 200lbs. between the bumper and fuel cell. That will make a bigger difference. This topic has been debated before, use the search for more info. Good Luck.

ryan
Dirt Freak

Total posts: 430
posted January 08, 2003 09:00 PM
I'' have to disagree with deeddude just a little bit. He will be moving more than 400lbs back 4 inches. I don't know how much a tranny and complete motor weigh together but its more than that(does anyone know for sure on a sbc) I just got done setting my motor back 3-4 inches and I figure if I gain at least a percentage point it will be worth it. I'll let you know in a couple months when its time to scale

dean_7585
Dirt Forum Racer

Total posts: 88
posted January 08, 2003 09:52 PM
It's not just moving weight back, It's getting it off the front. So if you only move a 1/2 % to the rear and possibly loose a 1/2 % of the front, That to me is a nice gain instead of having to add a bunch more weight to get your numbers. Putting weight by your pedals really isn't a good way figure that, because your trany sits farther back than that and there again it's more rear %.

DEEDDUDE
Dirt Maniac

Total posts: 111
posted January 09, 2003 11:17 AM
A small block Chevrolet weighs less than 500lbs and 100lbs for the trans. You will be moving about 600lbs. 3" to 4". Both of you guys have valid points. Maybe I should re-think this. I do know of a guy that moved his engine and trans. back 7". It made less than 1% in additional rear weight. He said that it wasn’t worth the effort. Maybe he’s just lazy. In one of the cars I built I moved the engine back 5”. There is a lot of unseen work to be done. Cut the cross member, shorter drive shaft, move firewall back, etc…The car I have now had over 55.5% rear w/ the engine in the stock location. I could have had even more. This was with most of the weight in front of the rear tires. Good luck let us know what you decide and how it turns out.

awkwardjeff
Dirt Freak

Total posts: 458
posted January 09, 2003 11:36 AM
First off......NOT to be hard on anyone...But do you think the fastest guys at your track give up ANY advantage because it's too much work??/ heck no, they want to WIN not see how little work they can do to run up front.

With that said, if you move the motor back you will have moved about 2 percent...IF you move everything back at the same time....like the radiator, shroud, fan, now you can cut off 4 inches of all the tubes ahead of the motor......move the front bumper back 4 inches.......ect. All this work will be worth about 2 percent.....and 2 percent is the differance from being a also ran to a winner.

ss38k
Dirt Full Roller

Total posts: 61
posted January 09, 2003 08:26 PM
Thanks alot guy's.hey Jeff and Ryan ,i cut my fire wall out before i read this. but you guy's talk me into it. we set up a complete dummy motor.an set it in place.slid it all back 4 inche's.now all the work start's.and yes i do have scales.i have to agree with Jeff .on what the other guy's are doing to win.i can get every thing but that win.even lead. till them better handing car get up to me. if i can get that 2%to the back that will be cool. that will be the ticket. i am also taking my 30lb flywheel off going to a triple disk that should help a bit.taking water pump off.

Thank's alot guy's .i will let you .know how it scale's out in a month or so Race On

DMS CEO
Dirt Freak

Total posts: 212
posted January 17, 2003 01:30 PM
Another tip is on short tracks raise it up as much as you can safely and that will make your weight work for you more than just sitting there. Works for me.

[This message has been edited by DMS CEO (edited January 17, 2003).]

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