spongy front springs

[v8260z]

Does anyone know of a front spring that is softer than the factory spring that can be used for drag racing (better weight transfer).The car has a custom fabbed frame,ladder bars,coil-over rear suspension,and weighs 2500# with driver. If anyone has any info it would be great. THANKS

[Guest JAMIE T]

Most Drag race Z's with solid axles, I have seen, are already wheel standing monsters Most of them could probably use front-end limiters attached to the control arm to limit front suspension travel, this helps to keep the front-end on the ground. If your car is done and you are racing it currently, and are having traction problems, I would look into the rear suspension pinion angle. If your still in the process of building the car, then I would finish it and see what happens. I have seen tubbed-out Z's doing wheel stands in the burnout box

 

Jamie

Deathstar

[DavyZ]

If your Z is a late model 260Z, then 240Z springs would be softer and be better for a good holeshot IMO. Otherwise, a racecar fabrication shop can custom wind you some to your specs. Per JTR, though, the stock front suspension is supposed to be really good for drag racing.

 

David

[Guest Anonymous]

Yeah, my 240z springs after I put in the V8 were super spongy (I have new springs just been lazy about getting them in there need bushings as well), heavier engine though being all cast, your car sounds pretty light with a V8 in it.

 

You could maybe go coil over, I've seen springs at www.afcoracing.com that are only 10" 2 5/8" 80 lb/in, I believe thats a bit lighter than a stock Z? Anyone know what the stock spring rate is?

 

Got any pictures of your ladder setup and frame? Be interested to see it.

 

Regards,

 

Lone

 

[ June 15, 2001: Message edited by: lonehdrider ]

[Guest kc6wfs]

Do you guys that drag race remove your front sway bar?

I was thinking of pulling mine next week and see if that helps transfer the weight to the rear quicker.

 

What do you do with the rear sway bar?

 

 

Dave

[v8260z]

Thanks for the info guys.To answer a few questions from the previous posts; the pinion angle is set at -1 degree. It's an early 260z.I have two or three pics of my frame and suspension. I am running the stock springs but I had to cut them to get the desired ride height (about 3 coils).I do currently race the car at H.R.P. and as of yesterday started driving the car on the street again.I can drive the car down the track just about with one finger.If anyone is interested in the best pass to date: 10.764 at 125.05 mph with a 1.543 60ft. foot stalling it to 1900rpm .

[v8260z]

I don't run a sway bar on my car and it did aid in traction. It's been five years since i removed it and i cant remember how much of an improvement it made at the track. I also had the stock open diff. under the car with Hoosier Quick Time tires and 3.70 gears. The best pass was 11.70s with that setup

[Guest Anonymous]

Dave,

 

I seem to recall Scottie saying he either removed or disconnected his rear bar for Drag racing. Front probably wouldn't make as much difference but I could be wrong.

 

Regards,

 

Lone

[pparaska]

v8260Z - Those are some impressive times. What's the rest of the drivetrain like? Engine, trans, etc.?

[Guest JAMIE T]

Those sure are impressive times. It doesn't seem to be having too much of a traction problem I think most of us here would like some more info on the set-up you are running.

 

Jamie

Deathstar

[v8260z]

This is the current set up of my 260: 2-bolt 350 .030 over,Speed pro .100 dome hypereutectic pistons with 1/8" plasma moly rings, stock rods and crank with ARP 190,000psi. bolts,balanced bottom end, 8" factory balancer. top end: Holley 750 d.p. with stub stack and integrated cold air box fed by glass cowl hood, Holley Contender idle to 7200 intake, this manifold is great for a street driven car by the way, have ran a sportsman and an rpm but prefer the Contender due to its larger ports, Sportsman 64cc angle plug heads with minor bowl work, custom ground Schneider hyd. roller cam: .480 .480 246 246 at .050" on a 108 center line installed straight up. (low lift for longevity on the street), Speed Pro lifters and pushrods, melling hi-volume oil pump, Aerospace Components electric water pump,Holley blue pump set at 7.5 psi, aluminum crank pulley to turn low mount alternator, MSD nascar distributor,6al box, timing computer w/2 degree retard at 6000 rpm controled by rpm activated switch, two step rev limiter 3000 and 7000 rpm (converter is too tight to use the 3000 off the line), MSD shift light set at 6000 rpm. Can anyone tell that I am a firm believer in MSD's products? Turbo 350, tci 10" converter, 10 bolt chevy rear narrowed, Richmond 4.10s, Strange spool, Mosier axles, c-clip eliminators,and Red Line synthetic diff. lube. Amsoil synthetic engine oil and filter. 1 3/4" tube full length block hugger headers with 9" collector ext. Best e.t. was on Exxon 108 leaded race gas, about 60 degree outside temp, 140 to 150 engine temp. Sorry if I bored anyone, but if anyone has questions about any other specs of the car let me know !

[Scottie-GNZ]

I have both sway bars removed and MOF they are now seeing duty in my buddy's 240Z doing X-cross and getting ready for stepping into ITS. After a lot of experimentation, I found removing both caused extreme squat but the best results with a best 60' of 1.55 on BFG DRs.

 

V8260Z, very impressive. DO you have any pics of your diff setup? I know what MikeKZ did and am impressed with that setup but looking for options. What kind of 60' times did you have with the open diff and were you gripping with both tires off the line?

 

I do not know about anyone else, but anyone that perform like that CANNOT bore me with the detailed specs of their setup.

[pparaska]

No, not bored with that at all! Thanks!

 

v8260Z, with those parts, it sounds like your in the 11+ to 1 compression ratio range. What is the compression ratio!

That cam (246@.050") would be pretty big on the street, I guess the 4.10s would help that a bunch. Is this a drag only car, or do you drive it on the street?

 

I have that Contender manifold on my 327. Glad to hear someone else sing it's virtues. I did pick up Mike Kelly's Victor Jr. I'll probably swap that on this Winter to see the differenece. My car is still in paint jail but I should be driving it for the first time in August.

 

[ June 17, 2001: Message edited by: pparaska ]

[Kevin Shasteen]

Your compression ratio depends on your Block Deck to Piston Deck Clearence. Did you have your block deck milled at all?

 

Then again-there are multiple types of dome pistons-does your pitson dome top also have a relief in it? Or is the dome fully extended above the piston w/out the valve relief going below the piston top deck plain? If you were using flat tops-this would be your way of working the comp.ratio.

 

As Pete illuded to-the books give an 11.1:1 to 11.2:1 Comp.Ratio for a .100 pop up. But what kind of Pop-Up is the question(?).

 

If your block is factory stock-then your Quench w/factory length rods & factory piston comp.height w/flat top pistons would actually yield you a 10.1:1 Compr.Ratio.

 

Figured like this:

 

Your Quench, .022", which represents the Block to Piston Deck Clearence. Take that figure & convert it to cubic inches & then convert that to cc's.

 

If you chose a head gasket w/.038" crushed thickness-you'ld do the same w/it-convert it to cubic inches & then convert that answer to cc's.

 

Now take those two answers in cc's and add them together: you should get 12.54cc's.

 

Add the 12.54cc's to your cylinder heads 64cc which yields 78.54: also add @ 2cc's for piston land volume.

 

Now take the displacement of your engine 350 & divide by 8-this gives you 43.75 cu.in. per cylinder; convert that answer to cc's which yeilds 716.93.

 

Now for the comp.ratio:

 

716.93 + 78.54/78.54 = 10.12:1 Comp.Ratio.

 

The books lists a .100 dome as yielding an 11.2 Comp.Ratio w/64cc heads-as Pete mentioned above. To know for sure we would need to know what head gasket thickness, Dome type, Quench/Squish achieved after milling (if the block was milled at all).

 

The unknowns are your block deck to piston clearence. Any milling of the block w/increase your compression.

 

Kevin,

(Yea,Still an Inliner)

 

[ June 17, 2001: Message edited by: Kevin Shasteen ]

[Guest dankinzle]

Amen, at least junk the rear swaybar if you're putting power down. After I got rid of my rear it made a huge difference. I never thought I'd actually use those adjustable shocks either. Happy I got them now.

[v8260z]

The block has not been decked and the piston part is #7070p if I am not mistaken.this yielded a 11.2 comp. ratio, might be a bit lower with the fel-pro perma-torque gaskets.I was not that concerned with the exact compression ratio of the engine at the time of building (close to 8 years ago). The car is now getting street use again after 4 years of being trailerd' to the track. I drove it for 4 years prior on the street as my primary vehicle.It had SR torquers on it w/76cc chambers for the first five years. future plans are a 6" rod 406 mech roller with AFR 210s and an internally balanced crank. I would love to have a 9sec. ride on the street. I could do it with NOS but I WONT ever run it on any engine I build. I would rather build the engine to run the number.

[BLKMGK]

Low mount alternator? Is the motor setback like the JTR or is it mounted Scarab style right over the stock mount pads? I tried a low mount alternator with the JTR and it ran smack into the setback plates. It apparently fits in a ZX fine...