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willyj
12-30-2010, 07:46 PM
We have purchased a mod ,it has a metric front with nova lowers,and the shocks are inboard.it has a multimount rear,currently4/4.Current springs are lf800-rf1050-lr225-rr175.lr is spring behind shock in front,rr is coilover in front.Lot of spring split up front huh?yes I will talk to the builder but would like to have some suggestions fro some who have this metric front.Oh with a rookie driver and the multimount would ya try a 4-z instead of the 4/4?

dsm_speeder
12-30-2010, 08:47 PM
I would change those front springs right off the bat. LF 700 RF 650 to start. Talk to the manufacturer and see what he says about rear bars, etc. But those front springs are messed up.

Bcollins82
12-30-2010, 09:46 PM
Yes, definitely get that spring out of the RF as stated, a 650 is usually a good starting point. On a car with the spring behind on the LR you need a softer spring in the RF to get the car up on the LR and it also helps keep the LF on the ground and makes the car more drivable. The 800 in the LF may not be all bad because it will make the car feel more secure on entry. I tell everyone I help to just start on the 4-4. Yes, it is a little more "finicky" but your gonna end up on it eventually unless you run on rough/tacky tracks all the time, so why not learn it? Your chassis builder should be able to get you close on angle, just don't make huge jumps and you'll be fine. One last suggestion is to get with a good shock builder because a 4-4 car on improperly valved shocks can just plain suck to drive.

racin6mod
12-31-2010, 09:54 AM
before telling a guy to throw on a 650# rf spring I would first ask what heads are you running?

Bcollins82
12-31-2010, 11:20 AM
before telling a guy to throw on a 650# rf spring I would first ask what heads are you running?



No, because I've had 4-4 cars with cast heads on springs softer than a 650RF, and we start out softer than that on all our cars with aluminum heads. So yes, a 650 is a good STARTING point on a RF spring in a metric/nova lower frontend on 4-4 with a spring behind on the LR.

willyj
01-01-2011, 04:37 PM
The eng. is a 409 all steel GM block with Motown 220 iron heads. I personally know the prev. owner as he had a all steel Dodge which he claims is a lot heavier than our sbc. I dont know how much either weigh but maybe he thought he needed this much spring. he quoted you (I) wont have to change spring its ready.

racin6mod
01-02-2011, 12:27 PM
A stock sbc is about 575# a mopar sb is between 525 and 560 depinding on year. now we went from a sbf 460# to a sbc and our rf bottomed out bad with a metric clip with nova lowers.some chassis builders raise or lower the motor and even the side to side location can change some.that all goes back to the builder I would start with what ever they say and tune off that.

zachmckenzieracing
02-05-2011, 04:45 AM
do your self some home work and research this matter. Spring rates are crucial to performance. Spring rates are calculated by many factors. In order to find the correct rates, you must go through the calculation process using the componets on your car. Every car is different, and require different rates.