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302 build, cam and spring questions!

2K views 17 replies 5 participants last post by  tripleblackvert 
#1 ·
I have a factory 302 short block that I've had a heads cam intake set up on for about a year, and I just pulled the engine for a few goodies and was wondering if id benefit from changing my valve springs to something lighter.

The set up is:

Brodix st 5.0r heads (59cc), 1 5/8 bbk long tubes
Anderson b25 cam. I have card for it. 218/228 510/511 112
Holley systemax, accufab race 70mm, 3.5in power pipe and Lmaf.

Car made 320whp 315trq and has ran a best of 7.67 @ 91mph @ 2800lbs 1.71 60ft

I'm going back with a 125 wet shot (plate), electric water pump, speed dr alt bracket, heater delete and while I have the heads off I was thinking I could find gains in some different springs, the current springs per Brodix are :

CC 987, 125 lb Closed, 325 lb open,
1.900 Installed Height.

I've been recommended ls1511ml springs and was wondering what you guys here thought about those on this set up.
 
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#2 ·
Car made 320whp 315trq and has ran a best of 7.67 @ 91mph @ 2800lbs 1.71 60ft
I wonder if my dyno or your dyno is lying lol

My car is 2800lbs

It made 335hp/335tq (and I am now estimating around 350)

Mine traps 98 - 99 mph thru the 1/8th

Normally runs 6.9-7.0s

A 15 - 30hp difference doesn't work out to an 8 mph difference in trap speed lol..either your dyno is too high or mine is too low lol

My old setup used to run about the same as yours..89-90 ish thru the traps...it had 270rwhp and the same 2809 lb race weight. I think your dyno is a bit high...

I can't say how much a lighter spring package will benefit you, although it definitely won't hurt.

I run a 1.300" lightweight LSX Style Lunati kit from Ed Curtis @ FTI... good for .660" lift, around 153 lbs on the seat. I'd contact him, I'm sure he has a similar package for your heads.
 
#3 ·
I believe yours is a little underrated or mustang dyno #s. Mine are dynojet. My 60ft isn't worth a damn either lol. I think I've seen your dyno on here and iirc your torque comes in a lot faster.

Here's mine


I feel like it should make power after 5800, not sure why it doesn't.
 
#4 ·
:leghump:I believe yours is a little underrated or mustang dyno #s. Mine are dynojet. My 60ft isn't worth a damn either lol. I think I've seen your dyno on here and iirc your torque comes in a lot faster.

Here's mine

I feel like it should make power after 5800, not sure why it doesn't.
Yours is STD, so take 10-15hp off of what you see. Comp 987 springs are worthless, if you really have them at 1.900 then you don't have the pressure you say you do.
 
#5 ·
When mine made 335/335 it was on a dyno jet

My old combo made 267 on (the same) dynojet, and 263 on a mustang dyno.

I'm pretty sure yours is over rating it.

Yours is probably dying at 5800 due to the valve springs. That's probably the most common reason cars die out at lower rpms than they should. Not enuff or too heavy of a valve spring package for the cam. Another reason would be not degreeing the cam in properly, and having it advanced a bit.
 
#6 ·
Cam was installed straight up as suggested.

Any spring reccomendation? I'm not worried about horsepower numbers on a dyno, it runs damn good IMO. Pulls harder after 4k then what it did with stock top end and a 125 shot at 1000psi.

Currently have it down to a bare block doing a rebuild.
 
#7 ·
Straight up doesn't mean it's degreed properly. Could be advanced, retarded, or dead on. But unless you measured with a degree wheel, you'll never know. Due to tolerances in your crank, timing set, the cam itself, etc.

Talk to Ed @ FTI. ..i bet he has a nice lightweight spring package for your heads. 1.300" OD, lightweight retainers, around 150 lbs on the seat and 400 open. That'll handle 7k rpms with ease. Probably pickup across the boards. The Comp 987s you're running aren't too great

This is what I run. He should have these for your heads
http://www.flowtechinduction.com/lunati-lsx-dual-valve-spring-kit-73925k2tw/
 
#8 ·
Straight up doesn't mean it's degreed properly. Could be advanced, retarded, or dead on. But unless you measured with a degree wheel, you'll never know. Due to tolerances in your crank, timing set, the cam itself, etc.

Talk to Ed @ FTI. ..i bet he has a nice lightweight spring package for your heads. 1.300" OD, lightweight retainers, around 150 lbs on the seat and 400 open. That'll handle 7k rpms with ease. Probably pickup across the boards. The Comp 987s you're running aren't too great

This is what I run. He should have these for your heads
Lunati LSx Dual Valve Spring Kit 73925K2TW - FlowTech Induction

I was gonna say the same thing you beat me to it. Those are the springs he recommended and they are looking great so far.
 
#12 ·
No, you cannot...:) Just put them on my AFR's and couldn't be happier even as of now...
 
#11 ·
Well he doesn't do recommendations or give advice without placing an order, and I'm not entirely sure that I need anything other then valve springs at this time.

Lunati LSx Dual Valve Spring Kit 73925K2TW - FlowTech Induction

If you guys say this will do me better then my current cc987s, then I'll take you guys word for it, maybe once I place this order he will tell me yay or nay.

Thanks again guys!

Edit:

Need a little more help if you guys don't mind, that spring kit is made for tfs tw heads, I had look on their site and they have some for afr heads as well.

Here's a link to my Brodix:
Brodix » ST 5.0 Series/20°

I guess im retarded but this is my first venture on getting springs other then just replacements and I want to do it right the first time, I'm not big on guess and check.

Thanks again.
 
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