shootin' for 7.50's

[skeeterbug]

I'm going for 7.50's with winter break mods. Last seasons best time as well as 2013 mods in sig. What y'all think? Makin or breakin I'm gettin 750's

[Marv D]

Myself,, targeting mid/high 11's might be a bit agressive ,,,, but only one way to tell

[skeeterbug]

yep...mat it, hang on and hope she dont BOOMM!

[hotrod 80]

Did i miis it ? What does it weigh . Your combo is close to mine except bigger head and more compression . Mine will run 10.90's @ 2900 #'s.

The rotational weight loss will help alot .

[Super73]

Originally Posted by hotrod 80

The rotational weight loss will help alot .

I need to start working on some of this. Perhaps when I build my 9"....
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[Marv D]

Originally Posted by hotrod 80

Did i miis it ? What does it weigh ....

Maybe I made some assumptions,, and we know how that goes., 71 LWB,, with only 200 pounds of body weight loss,,... I kind of assument at least 3800to 4000,,, maybe 4200 in full trim? Anyone have a feel? I think Regan said his was somewhere in that range.

[skeeterbug]

I really need to get it weighed, tomorrow im bringing it back to work to finish up piecing together the wheel tubs. There is a pilot truck stop w/ a scale around the corner mabey they will let me pay to weight. Just guessing i would say 4000 or a little less, aluminum bed floor, no rear bumper, one kirkey pro seat,carpet,hushmat, gauges and shifter. rest of interior creature comfort's gone.

[Marv D]

Originally Posted by skeeterbug

I really need to get it weighed, tomorrow im bringing it back to work to finish up piecing together the wheel tubs. There is a pilot truck stop w/ a scale around the corner mabey they will let me pay to weight. Just guessing i would say 4000 or a little less, aluminum bed floor, no rear bumper, one kirkey pro seat,carpet,hushmat, gauges and shifter. rest of interior creature comfort's gone.

Given that... I bet she is down around 3500 range.
Make SURE and place the truck to get FRONT and REAR axle weights not just a total. It will be invaluable info as you start tunning the suspension.

[skeeterbug]

Thanks for reminding me MarvD, i will do that.

[skeeterbug]

Gonna hi jack my own thread here for a minute, whats yalls take on pluging the powervalve(s)? Since i no longer drive my truck on the street can i plug one or both powervalves and possible get rid of a minor initial hitt stumble? Ive heard several different ways of going about it on other sites, some say plug rear only some say both other say not at all.

[hotrod 80]

It is scary how close our combos are . Same short block specs ( different brand names ) The only motor differences are the pistons , i have dish with smaller chambers im sure (60CC) , and heads those 215 spier heads probably flow better . I had bad luck with the 750R QFT on my truck . It just never worked right .

With that said and out of the way (sorry Marv) , A stumble is a lean spot on transistion from the idle circuit to the primary jet circuit . Pulling the power valve will need to be compensated for with primary jet and pump cam . It depends on how your racing the truck . Off a footbrake i like the powervalve adding the fuel on the way open . What jets are in it now and what power valve is in it . I am at 72 f and 80 rear with a 6.5 pv . I have yet to chassis dyno it with an 02 sensor , so this is where it runns good and is consistant . You also have alot more weight to move than me . Im at 2900 with me and im 250

[bigboybodry]

looking good! What style hole shots are you going to run? I have two sets and they have been great wheels/great people to work with.

[shortbed70]

Wow 3.73-5.13's... Hope it hooks! That's a big jump in gear. I'm curious to see how it does because I'm looking at running a 5.3 ls and glide with 4.88-5.13 gear for my 8th mile track... I think 7.50's should be in the works 8th mile! My buddy was running 7.90's in a 74 Lwb 29-10.5 slicks, glide 3200 foot brake, 4.10's 12-1 355! No tailgate or interior 6 gallons o fuel.
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[skeeterbug]

hotrod 80, yes i run the truck off footbrake with 74 f and 84 r with 4.5 powervalve that it came with. idle in gear vacum jumps around between 10 and 11in. HG, i have a new in the package (6.5in. HG) four door power valve on my desk here i was thinking of trying.
Thanks bigboybodry they are Revolvers by holeshot and i will second that they are great wheels/ and people to work with.
shortbed70 yes i only made such a huge jump because of the tire size i went with and with the old 28x11.5 i run last season the truck didnt hit high gear till right before the stripe.

[Marv D]

I 10000% agree with hotrod,,, leave the powervalve in it. Unless your launching off a transbrake / low side limiter at WOT and WAY up in the RPM range you will be much better off allowing the carb to transition as it was designed. 'Typically' you only see powervalves plugged front and rear when your launching at like 5000 off a brake / sidestepping the clutch and shifting up above the top of the HP peak.

Generally you jump 8-10 jet sizes when you plug the powervalve. Think about how that effects the lower RPM's.

The 920 Prosystems dominator I ran on the old 383 even has the soft linkage and a powervalve in the primary (10.50 car launching at 4800 shifting at 7200)

[skeeterbug]

I guess I will try replacing the front 4.5 with a 6.5 pv since vacuum is between 10 and 11 HG with trans in gear.

[skeeterbug]

Well put the 6.5 pv in the front yesterday morning before we went to test and tune, run great no stumble. Got to the track first pass launched hard, broke loose, hooked and broke the main caps in the rear taking the rear u joints with it lol. fail! Time for billett caps, solid u joints, and LPW ultra pro support cover.

[prostreetC-10]

wait.....are we talking 1/8th or 1/4 mile?


Nevermind.....just read your signature.

[djracer]

I'll be glad when I can shoot for 7's ...................................in the quarter! Maybe one day I will get back to the track!
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[hotrod 80]

Originally Posted by skeeterbug

Well put the 6.5 pv in the front yesterday morning before we went to test and tune, run great no stumble. Got to the track first pass launched hard, broke loose, hooked and broke the main caps in the rear taking the rear u joints with it lol. fail! Time for billett caps, solid u joints, and LPW ultra pro support cover.

Sounds like your on the right track . I may piss some people off , but i dont see a rerason to plug the powervalve footbraking . No need to run around the pits at 5 to 1 A/F ratio killing plugs .

[skeeterbug]

Finally got the broken 12 bolt problem fixed, Ford 9" junkyard donor. Had Moser Eng. narrow it, fab up some 35 splines, spool, back brace, and big bearings. It has been raining every weekend around here but i managed to get a few friday test n tune passes in, everything holding up great but...cant get it to hook. Still run best of 7.48 @ 91 w/ 1.68 60' spinning like heck from launch probably first 25-30 feet out. I moved the 45# battery to the bed hoping that will help this friday we will see. I know there are other members whom have had to add weight to get traction, how much?

[Super73]

I added weight, but it was not needed on a prepped track. I only needed it at an event i raced once a year called Eagle Field Drags where there was

ZERO track prep
No water box for burn out
Rule was no standing burn out, rolling only
And Dust was what you ate all day as the wind blew it on the track.

Get your suspension and tire right and I doubt you need to add weight.
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[skeeterbug]

That sounds like a difficult event to race at, i have played with the rebound on the rear coilovers with no sucess. Im running 200# springs now, may need to try lighter spring rate? i wonder if adj. front shocks would help, the 2" drop springs in the front are not helping matters im sure because they are so stiff.

[Super73]

My advise,

Change the front springs
Put an adjustable front shock
Go try it
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[skeeterbug]

Yea i think thats what im gonna have to do. Are you running some type of drag spring up front Moroso chevelle spring or landrum? I contacted landrum back several months ago and didnt have the front weight so i didnt order any.