1.72RR's & SVO Valve Springs = 6000RPM On A Stock 5.0!!!

BowTie Eater 5 Liter · 04-21-2001, 02:15 PM

Ok, the question I have for all of you is about something I read in Muscle Mustangs & Fast Fords May 2001 issue under the ask Bernie Colum, it says with SVO valve springs(#m6513-a5) & 1.72 roller rockers "then rpm to 6000 with ease" well, if this is so, I think that will be my first mod, but anyone ever herd of this before? I guess i can trust this information.

Anyone know what kind of 1.72 roller rockers to get to fit the stock heads??? ( if you have the part # I would aprecciate them)

Thanks....

------------------
1988 Mustang GT, T-5
3.08's, No Smog Pump (Shorty Belt), Dumps At The End Of Stock H-Pipe, K&N Air Filter (Stock Air Box), Removed air silendcer), 198.9 rwhp @4200 (235 Motor!!), 285 lbs-ft @2900 (336 Motor!!!).
My Stang
My Site (Not Done Yet)

exgmguy · 04-21-2001, 02:24 PM

Sure, I am sure you could zing it to 6 grand in neutral! The powercurve would still fall on it's face after 5 grand.

BowTie Eater 5 Liter · 04-21-2001, 02:28 PM

it says that he could shift at 6k where he is now shifting at 5250

Unit 5302 · 04-21-2001, 02:28 PM

The 1.72:1 roller rockers will necessitate the removal of the rail running on the inside top of the valve covers, otherwise you'll run into clearance problems. I'm not sure what pushrods the 1.72:1 RR use, that may be something you'll also have to replace.

Why are you suprised to see 6000rpms? The stock 5.0 redlines at 5900 not because of the engines reliability factor at higher rpms, more because it's not designed to make power beyond that.

The stock hydraulic lifters begin pumping up as the r's really climb, but they should do fine till fuel cutoff at 6250rpms without a whole lot of difficulty. I wouldn't be scared to send the stock rotating assembly to 7000rpm. Just not with those lifters. What would it matter anyway, you're not making power up there at all.

It's not like switching to 1.72:1 RR will be making good power at 6k anyway. You are limited by heads, and exhaust, along with intake.

BowTie Eater 5 Liter · 04-21-2001, 02:31 PM

could i use the factory rockers & everything & just change the valve springs??? it would still rev as good without the 1.72rrs right?

------------------
1988 Mustang GT, T-5
3.08's, No Smog Pump (Shorty Belt), Dumps At The End Of Stock H-Pipe, K&N Air Filter (Stock Air Box), Removed air silendcer), 198.9 rwhp @4200 (235 Motor!!), 285 lbs-ft @2900 (336 Motor!!!).
My Stang
My Site (Not Done Yet)

StreetStang37 · 04-21-2001, 05:31 PM

You still won't be making power much past 5000. And to install springs, I heard you need to remove the head(s) anyways.

------------------
1993 Mustang GT - March Ram Air & Pullies, K&N, C&L 73mm MAF, 3.73 Gears, Super Competition Hooker Headers, 2 1/2 in. mandrel bent cat back, High Flow H-Pipe, Pro 5.0 Shifter, 16* Timing Advance

82 GT · 04-21-2001, 06:17 PM

Bowtie, I think what these people are trying to tell you,and I agree, is that you need more mods besides 1:72 rockers to see anymore power past 5200.
The cam determines where the engine makes it's power and then you need good heads, exhaust,T/B, intake, etc. to compliment the new cam profile.

------------------
'82 GT 351W C-4,BBK headers,Carter 625 carb,Comp.Cam,Flowmaster exhaust.
1988 GT...T-5,bone stock

juiceman · 04-22-2001, 12:32 AM

do those mods first as it will be very easy to make power at 6000. you do not need to change cam or heads to make power there. intake would be a good choice though. the crane energizers fit in stock covers and are cheap and good. its what was used on the cobras and i use them for alot of motors. look at it like this, in all those bone stock classes where nothing is able to be changed theyre going low 12's. and there reving to 6000. be smart, save money and go fast. good luck.

StreetStang37 · 04-22-2001, 03:20 AM

Most cars make power at 6000, just depends on how much. It may not be worth going that high if you have MORE power down lower.

------------------
1993 Mustang GT - March Ram Air & Pullies, K&N, C&L 73mm MAF, 3.73 Gears, Super Competition Hooker Headers, 2 1/2 in. mandrel bent cat back, High Flow H-Pipe, Pro 5.0 Shifter, 16* Timing Advance

JP85gt · 04-22-2001, 01:51 PM

Why spend your money on everything but the cam when the cam is the main thing that will stop you from making power from 5-6 even with a new cam and stock stuff i can see 5500 but not 6. Just telling you what i have found in fooling with mine when i was on my way to going fast *still on my way * lol

juiceman · 04-23-2001, 03:14 PM

it is already know in drag racing that reving the motor will make you go faster, hence the 9000 rpm revs in all the high classes. stock cam will not hurt you at 6000 with 1.7 rockers. if you have a problem making power at 6000 its not the cam its you. you would be surprised how fast those motors can go in stock trim. do the small stuff first. its always better to build a motor that is strong before trying to make power. what good is all that power if you can only use it once?

04-21-2001, 02:15 PM	#1
BowTie Eater 5 Liter Registered Member Join Date: Nov 2000 Location: Maple Ridge B.C. Canada, The Best Place In The World Posts: 871	1.72RR's & SVO Valve Springs = 6000RPM On A Stock 5.0!!! Ok, the question I have for all of you is about something I read in Muscle Mustangs & Fast Fords May 2001 issue under the ask Bernie Colum, it says with SVO valve springs(#m6513-a5) & 1.72 roller rockers "then rpm to 6000 with ease" well, if this is so, I think that will be my first mod, but anyone ever herd of this before? I guess i can trust this information. Anyone know what kind of 1.72 roller rockers to get to fit the stock heads??? ( if you have the part # I would aprecciate them) Thanks.... ------------------ 1988 Mustang GT, T-5 3.08's, No Smog Pump (Shorty Belt), Dumps At The End Of Stock H-Pipe, K&N Air Filter (Stock Air Box), Removed air silendcer), 198.9 rwhp @4200 (235 Motor!!), 285 lbs-ft @2900 (336 Motor!!!). My Stang My Site (Not Done Yet)

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
valve springs	289	Windsor Power	2	11-11-2003 08:13 AM
HARTMAN VALVE COVERS ARE JUNK NEED TO KNOW WHAT I NEED TO GRIND OFF STOCK	dirtyGT	Windsor Power	4	09-14-2001 09:30 AM
Roller Rockers And Stock Valve Covers	PMDFoxbody5.0	Blue Oval Lounge	3	06-07-2001 12:44 AM
hi-performance valve springs	stangbang	Windsor Power	0	03-24-2001 05:19 PM
Need some professional advice - head work, valve springs, rockers, cam. pretty long.	AxemanZZ	Windsor Power	15	01-11-2001 01:30 PM

04-21-2001, 02:24 PM	#2
exgmguy Registered Member Join Date: Feb 1999 Location: Utica, Michigan Posts: 2,631	Sure, I am sure you could zing it to 6 grand in neutral! The powercurve would still fall on it's face after 5 grand.

04-21-2001, 02:28 PM	#3
BowTie Eater 5 Liter Registered Member Join Date: Nov 2000 Location: Maple Ridge B.C. Canada, The Best Place In The World Posts: 871	it says that he could shift at 6k where he is now shifting at 5250

04-21-2001, 02:28 PM	#4
Unit 5302 Registered Member Join Date: May 1999 Posts: 5,246	The 1.72:1 roller rockers will necessitate the removal of the rail running on the inside top of the valve covers, otherwise you'll run into clearance problems. I'm not sure what pushrods the 1.72:1 RR use, that may be something you'll also have to replace. Why are you suprised to see 6000rpms? The stock 5.0 redlines at 5900 not because of the engines reliability factor at higher rpms, more because it's not designed to make power beyond that. The stock hydraulic lifters begin pumping up as the r's really climb, but they should do fine till fuel cutoff at 6250rpms without a whole lot of difficulty. I wouldn't be scared to send the stock rotating assembly to 7000rpm. Just not with those lifters. What would it matter anyway, you're not making power up there at all. It's not like switching to 1.72:1 RR will be making good power at 6k anyway. You are limited by heads, and exhaust, along with intake.

04-21-2001, 02:31 PM	#5
BowTie Eater 5 Liter Registered Member Join Date: Nov 2000 Location: Maple Ridge B.C. Canada, The Best Place In The World Posts: 871	could i use the factory rockers & everything & just change the valve springs??? it would still rev as good without the 1.72rrs right? ------------------ 1988 Mustang GT, T-5 3.08's, No Smog Pump (Shorty Belt), Dumps At The End Of Stock H-Pipe, K&N Air Filter (Stock Air Box), Removed air silendcer), 198.9 rwhp @4200 (235 Motor!!), 285 lbs-ft @2900 (336 Motor!!!). My Stang My Site (Not Done Yet)

04-21-2001, 05:31 PM	#6
StreetStang37 Registered Member Join Date: Dec 2000 Location: San Jose, California USA Posts: 275	You still won't be making power much past 5000. And to install springs, I heard you need to remove the head(s) anyways. ------------------ 1993 Mustang GT - March Ram Air & Pullies, K&N, C&L 73mm MAF, 3.73 Gears, Super Competition Hooker Headers, 2 1/2 in. mandrel bent cat back, High Flow H-Pipe, Pro 5.0 Shifter, 16* Timing Advance

04-21-2001, 06:17 PM	#7
82 GT Import Slayer Join Date: May 1999 Posts: 2,241	Bowtie, I think what these people are trying to tell you,and I agree, is that you need more mods besides 1:72 rockers to see anymore power past 5200. The cam determines where the engine makes it's power and then you need good heads, exhaust,T/B, intake, etc. to compliment the new cam profile. ------------------ '82 GT 351W C-4,BBK headers,Carter 625 carb,Comp.Cam,Flowmaster exhaust. 1988 GT...T-5,bone stock

04-22-2001, 12:32 AM	#8
juiceman Registered Member Join Date: Jan 2001 Location: ny Posts: 197	do those mods first as it will be very easy to make power at 6000. you do not need to change cam or heads to make power there. intake would be a good choice though. the crane energizers fit in stock covers and are cheap and good. its what was used on the cobras and i use them for alot of motors. look at it like this, in all those bone stock classes where nothing is able to be changed theyre going low 12's. and there reving to 6000. be smart, save money and go fast. good luck.

04-22-2001, 03:20 AM	#9
StreetStang37 Registered Member Join Date: Dec 2000 Location: San Jose, California USA Posts: 275	Most cars make power at 6000, just depends on how much. It may not be worth going that high if you have MORE power down lower. ------------------ 1993 Mustang GT - March Ram Air & Pullies, K&N, C&L 73mm MAF, 3.73 Gears, Super Competition Hooker Headers, 2 1/2 in. mandrel bent cat back, High Flow H-Pipe, Pro 5.0 Shifter, 16* Timing Advance

04-22-2001, 01:51 PM	#10
JP85gt Registered Member Join Date: Feb 2000 Location: Louisville,KY Posts: 27	Why spend your money on everything but the cam when the cam is the main thing that will stop you from making power from 5-6 even with a new cam and stock stuff i can see 5500 but not 6. Just telling you what i have found in fooling with mine when i was on my way to going fast still on my way lol

04-23-2001, 03:14 PM	#11
juiceman Registered Member Join Date: Jan 2001 Location: ny Posts: 197	it is already know in drag racing that reving the motor will make you go faster, hence the 9000 rpm revs in all the high classes. stock cam will not hurt you at 6000 with 1.7 rockers. if you have a problem making power at 6000 its not the cam its you. you would be surprised how fast those motors can go in stock trim. do the small stuff first. its always better to build a motor that is strong before trying to make power. what good is all that power if you can only use it once?