what should my lift be with these 1.7's

Chevysucks · 05-16-2002, 11:46 AM

I have been told that The 1.7 crane cams roller rockers moves your lift up some.
I have the x-303 cam and thats 542 lift and i was wandering waht it really is with the 1.7's that i have.
thanks.

Skyman · 05-16-2002, 12:21 PM

Should be around 576lift. You have stock heads? This probably is kinda mismatched.

SKyler

gtsr515 · 05-16-2002, 02:33 PM

The difference between 1.6 and 1.7 rockers is .30

Yours would be .572 lift.

fiveohpatrol · 05-16-2002, 03:17 PM

wow, gtsr515 is wrong for once

the 1.7 or 1.6 is a ratio. You multiply the lobe lift by this ratio to get total lift.
Lets take for example a B-303 (mainly because its the only cam that i know the lobe lift off the top of my head) it's lobe lift is .300" multiply by 1.6 and you get the advertised .480" total lift.

If you dont know the lobe lift of a particular cam, all you need to do is take a ratio of ratios, divide the new rocker ratio by the old, then multiply by the advertised total lift. if you have 1.7's with a B-303, then (1.7/1.6)x0.480 = 0.510"

in your case, (1.7/1.6)x0.542 = 0.575875" (so Skyman is right)

I sure hope you have some serious valve relief's in your pistons.
Also i agree that that is wayyy too much for stock heads, try to keep it around .500"

Skyman · 05-16-2002, 03:27 PM

fiveoh you are right on.. Its a ratio, not a straight across #. But for cams around 500 lift .30 is usually about right.

Skyler

gtsr515 · 05-16-2002, 03:29 PM

Hey! I was wrong once before many years ago, that makes twice now, get your facts straight!

Regardless, that's too much lift.

Chevysucks · 05-16-2002, 05:19 PM

hey skyman, I was talking to the guy that orrigonally owned the car when he had it running 13.00 and he said that the heads are gt40x's but when i put the 1.7's on i looked and it didnt say gt40x anywhere it just said gt , so i assumed that they are just heads from a gt mustang that have work done to them cause they flow pretty good.

And hows your new combo?

Skyman · 05-17-2002, 07:34 PM

Havn't got my car back together yet, still porting the heads and intake (goes real slow).

See if the heads are aluminum or Iron. If they are iron they are probably GT40 iron heads. If they are aluminum then they are probably the GT40X.

Skyler

TJR · 05-18-2002, 12:04 PM

Quote:

If they are iron they are probably GT40 iron heads.

I believe the iron heads have 3 bars on the outside ends of the casting (near the bottom), you might be able to see them.

Quote:

If they are aluminum then they are probably the GT40X.

Could also be the GT40Y.

Unit 5302 · 05-18-2002, 12:46 PM

Am I the only one that noticed "soon to be AFR 185's" in his post?

Regardless, I can't figure out why you need such a monster cam. You don't have the engine for it, even with 185's. Not even close. What's the max lift on those AFR 185 springs? Probably gonna be doin some flycutting too.

Chevysucks · 05-19-2002, 12:26 PM

unit- I didnt put the cam in it or the heads. It was all like it when i got it.. The only thing that I did to it was put 1.7's and crane cams hardend pushrods in it because the pushrods that were in it were way to short. When the guy had it before me he said it ran 13.0 and a 13.16 on slicks. He said that he broke two transmissions thats why he wanted to get rid of it.

If my heads were gt40 or gt40x's wouldnt it say it on the out side or under the covers. all it says under the covers its GT. And yes they are cast iron.
You guys tell me how to post a pic and ill post them , i just scanned them today.

fiveohpatrol · 05-19-2002, 04:00 PM

to post a picture, all you have to do is hit the browse button inderneath the area that you type in when you reply to a post. Its titled Attach file: on the left hand side of the screen

I believe you may have GT-40's, i think all they said on the head was GT, not GT40.

93GTDIN · 05-19-2002, 06:31 PM

here's a slightly related question:

If I have 1.6 rr's, 202/160 that flow 295/231 @.600" lift, what kind of cam can I run to get maximum lift without having to worry about piston/valve clearance issues on a 331 ci?

05-16-2002, 11:46 AM	#1
Chevysucks Registered Member Join Date: Mar 2000 Location: Stroudsburg, PA, USA Posts: 150	what should my lift be with these 1.7's I have been told that The 1.7 crane cams roller rockers moves your lift up some. I have the x-303 cam and thats 542 lift and i was wandering waht it really is with the 1.7's that i have. thanks. __________________ 88 Stang 306 ci. GT Mustang heads- ported and polished/milled---Soon to be AFR 185cc 1.7 crane roller rockers/extra hardened pushrods FRPP X-303 Cam Stock Intake-1 inch intake spacer BBK Cold Air Induction Stock Injectors--going to 24 pounders BBK Full Length Headers Mac 2.5 inch Cat-Back 8 Point Cage Sub Frame Connectors World Class T-5 Steeda Shift Cable,Quadrant,Firewall adjuster King Cobra Clutch Pro 5.0 Shifter Alunimum Driveshaft/ Drive shaft loop Kenny Brown suspension 3.55 gears

05-16-2002, 12:21 PM	#2
Skyman I need 110mph Trap Speed! Join Date: Feb 1999 Location: So, CA Posts: 4,315	Should be around 576lift. You have stock heads? This probably is kinda mismatched. SKyler __________________ 2001 BMW M3 6spd 12.79@108 RIP ---- 1993 Notch w/ 98 4V 4.6 Fasttt... -1989 Saleen Mustang #406- 12.32@109 -1999 Black Cobra Coupe- JBA Shorties, Bassani Cat-X, Magnaflow 3", Pulleys, 85mm Pro-M, Ported Intake, Soild Rear w/ 4.30s, Tubular Front End, X2C arms, 13lb batt, few others.

05-16-2002, 02:33 PM	#3
gtsr515 Registered Member Join Date: Nov 2001 Location: Sunny, Hot, Sebring, Florida Posts: 725	The difference between 1.6 and 1.7 rockers is .30 Yours would be .572 lift. __________________ Remember...2nd place is 1st place for losers!

05-16-2002, 03:17 PM	#4
fiveohpatrol I'd rather be basketweaving Join Date: Feb 2000 Location: Indianapolis Posts: 2,551	wow, gtsr515 is wrong for once the 1.7 or 1.6 is a ratio. You multiply the lobe lift by this ratio to get total lift. Lets take for example a B-303 (mainly because its the only cam that i know the lobe lift off the top of my head) it's lobe lift is .300" multiply by 1.6 and you get the advertised .480" total lift. If you dont know the lobe lift of a particular cam, all you need to do is take a ratio of ratios, divide the new rocker ratio by the old, then multiply by the advertised total lift. if you have 1.7's with a B-303, then (1.7/1.6)x0.480 = 0.510" in your case, (1.7/1.6)x0.542 = 0.575875" (so Skyman is right) I sure hope you have some serious valve relief's in your pistons. Also i agree that that is wayyy too much for stock heads, try to keep it around .500" __________________ NMRA O/C 9516 NA pumpgas stickshift 347 10.65@125.6, 6.73@100, 1.41 60ft

05-16-2002, 03:27 PM	#5
Skyman I need 110mph Trap Speed! Join Date: Feb 1999 Location: So, CA Posts: 4,315	fiveoh you are right on.. Its a ratio, not a straight across #. But for cams around 500 lift .30 is usually about right. Skyler __________________ 2001 BMW M3 6spd 12.79@108 RIP ---- 1993 Notch w/ 98 4V 4.6 Fasttt... -1989 Saleen Mustang #406- 12.32@109 -1999 Black Cobra Coupe- JBA Shorties, Bassani Cat-X, Magnaflow 3", Pulleys, 85mm Pro-M, Ported Intake, Soild Rear w/ 4.30s, Tubular Front End, X2C arms, 13lb batt, few others.

05-16-2002, 03:29 PM	#6
gtsr515 Registered Member Join Date: Nov 2001 Location: Sunny, Hot, Sebring, Florida Posts: 725	Hey! I was wrong once before many years ago, that makes twice now, get your facts straight! Regardless, that's too much lift. __________________ Remember...2nd place is 1st place for losers!

05-16-2002, 05:19 PM	#7
Chevysucks Registered Member Join Date: Mar 2000 Location: Stroudsburg, PA, USA Posts: 150	hey skyman, I was talking to the guy that orrigonally owned the car when he had it running 13.00 and he said that the heads are gt40x's but when i put the 1.7's on i looked and it didnt say gt40x anywhere it just said gt , so i assumed that they are just heads from a gt mustang that have work done to them cause they flow pretty good. And hows your new combo? __________________ 88 Stang 306 ci. GT Mustang heads- ported and polished/milled---Soon to be AFR 185cc 1.7 crane roller rockers/extra hardened pushrods FRPP X-303 Cam Stock Intake-1 inch intake spacer BBK Cold Air Induction Stock Injectors--going to 24 pounders BBK Full Length Headers Mac 2.5 inch Cat-Back 8 Point Cage Sub Frame Connectors World Class T-5 Steeda Shift Cable,Quadrant,Firewall adjuster King Cobra Clutch Pro 5.0 Shifter Alunimum Driveshaft/ Drive shaft loop Kenny Brown suspension 3.55 gears

05-17-2002, 07:34 PM	#8
Skyman I need 110mph Trap Speed! Join Date: Feb 1999 Location: So, CA Posts: 4,315	Havn't got my car back together yet, still porting the heads and intake (goes real slow). See if the heads are aluminum or Iron. If they are iron they are probably GT40 iron heads. If they are aluminum then they are probably the GT40X. Skyler __________________ 2001 BMW M3 6spd 12.79@108 RIP ---- 1993 Notch w/ 98 4V 4.6 Fasttt... -1989 Saleen Mustang #406- 12.32@109 -1999 Black Cobra Coupe- JBA Shorties, Bassani Cat-X, Magnaflow 3", Pulleys, 85mm Pro-M, Ported Intake, Soild Rear w/ 4.30s, Tubular Front End, X2C arms, 13lb batt, few others.

05-18-2002, 12:46 PM	#10
Unit 5302 Registered Member Join Date: May 1999 Posts: 5,246	Am I the only one that noticed "soon to be AFR 185's" in his post? Regardless, I can't figure out why you need such a monster cam. You don't have the engine for it, even with 185's. Not even close. What's the max lift on those AFR 185 springs? Probably gonna be doin some flycutting too.

05-19-2002, 12:26 PM	#11
Chevysucks Registered Member Join Date: Mar 2000 Location: Stroudsburg, PA, USA Posts: 150	unit- I didnt put the cam in it or the heads. It was all like it when i got it.. The only thing that I did to it was put 1.7's and crane cams hardend pushrods in it because the pushrods that were in it were way to short. When the guy had it before me he said it ran 13.0 and a 13.16 on slicks. He said that he broke two transmissions thats why he wanted to get rid of it. If my heads were gt40 or gt40x's wouldnt it say it on the out side or under the covers. all it says under the covers its GT. And yes they are cast iron. You guys tell me how to post a pic and ill post them , i just scanned them today. __________________ 88 Stang 306 ci. GT Mustang heads- ported and polished/milled---Soon to be AFR 185cc 1.7 crane roller rockers/extra hardened pushrods FRPP X-303 Cam Stock Intake-1 inch intake spacer BBK Cold Air Induction Stock Injectors--going to 24 pounders BBK Full Length Headers Mac 2.5 inch Cat-Back 8 Point Cage Sub Frame Connectors World Class T-5 Steeda Shift Cable,Quadrant,Firewall adjuster King Cobra Clutch Pro 5.0 Shifter Alunimum Driveshaft/ Drive shaft loop Kenny Brown suspension 3.55 gears

05-19-2002, 04:00 PM	#12
fiveohpatrol I'd rather be basketweaving Join Date: Feb 2000 Location: Indianapolis Posts: 2,551	to post a picture, all you have to do is hit the browse button inderneath the area that you type in when you reply to a post. Its titled Attach file: on the left hand side of the screen I believe you may have GT-40's, i think all they said on the head was GT, not GT40. __________________ NMRA O/C 9516 NA pumpgas stickshift 347 10.65@125.6, 6.73@100, 1.41 60ft

05-19-2002, 06:31 PM	#13
93GTDIN Registered Member Join Date: Jan 2001 Location: Live music capital of the world, TX Posts: 324	here's a slightly related question: If I have 1.6 rr's, 202/160 that flow 295/231 @.600" lift, what kind of cam can I run to get maximum lift without having to worry about piston/valve clearance issues on a 331 ci? __________________ 96 Cobra - a bit too stock. 14.0 @ 101

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