Highest lift cam on stock pistons

QuantumMotorsports · 05-28-2001, 09:45 PM

What's the highest lift cam you guys have ran on stock pistons without clearance probs? I want to run a motorsport X303 cam. I believe lift is .542 Does anyone know if this cam will work with stock pistons? Also, is anyone running a similar combo?
Stock shortblock (or 306, 308)
ported E7TE heads
GT40 lower
Cobra Upper
65mm throttle body
24# injectors
X303 cam
1 5/8 equal length shorties
2.5" H pipe
40 series flowmasters
underdrive pulleys

If anyone has a similar combo, what kind of power are you making? or E/Ts? My cougar weighs 3500 and I will have 3.73 gears, it is a 5 speed. Any estimates on E/Ts?? I'm planning on building this engine this summer and have some of the parts already, I'm thinking hopefully mid to low 13s. What do you guys think? Thanks.

------------------
Michael Black
Quantum Motorsports
Norman, Oklahoma

1988 Merc Cougar 5.0 HO, Ported and Polished E7TEs, 2.25" duals w/ 2 chamber flowmasters, T5 tranny
New E/T!!!
14.626 @ 94.94mph, 2.194 60' time, a little better than last time. Keep in mind this thang is heavy (3590lbs) Finally 14s!!!!

Idhomustang · 05-28-2001, 10:31 PM

If you are building you will not know until you check. Try and get .100 on ex. and the same on the intake side. This is plenty
of clearance.Every engine is different even if made on the same day by the same man.
Good luck, hope you get the ponies you need, to kick some bow-tie butt.

Idaho Mustang

------------------
393,9.5" 351W
830 Holley HP
Victor Jr.
Home made Cool Air Pan
Pro Billet MSD

Mach 1 · 05-29-2001, 01:51 AM

yes, it will clear stock pistons. i have more lift, and mine clears. with 5 speed, low 13's should be no problem

------------------
1993 GT/AOD
'93 Mustang GT

2FastLX · 05-29-2001, 09:36 AM

I am running a similar combo but with a GT-40 upper and F303 cam. I can tell you I was VERY close to the minimal clearance with this cam (.512 lift) and .030 shaved from my heads, which if you figure it is about the same as you will be. You should be close so I would check it with some clay just to be safe.

It will definately be a 13 second car. With gears and traction you could come close to 12's but with a car that heavy it may take a 50 shot =)

------------------
Too much to list. Best ET on the car so far with stock 2.73 gears - 13.73@102mph

Indiana Stangers Association
Buy your parts here
ICQ# 42269241

QUIN · 05-29-2001, 11:10 AM

i would not use 1.7 rr'ers either. have to recoment replacing the stock ones with a nice set of 1.6'es.
Q

------------------
Quin, 87 GT,306,forged/cut pistons,edelbrock head\intak,steeda#18cam,1.7rr,MSD Blaster tfi coil,A9L,pro-m75mm,24#inj,accufab65mm,2.5"pipes,hooker headers,dynomax exhaust,3.73 gr,110 lph fp,180*therm,moroso cold air,ASP pullies, weld rims

See my engine on user rides.

I see your shwartz is as big as mine, now lets see how well you handle it!

86GT · 05-29-2001, 03:56 PM

Definitely clay the pistons to check clearance, its the only way to be sure.

I've got an F cam with 1.90/1.60 valves, 1.6 RR, no problems with it.. Had .117" on intake, .118" on exhaust.

QuantumMotorsports · 05-29-2001, 07:05 PM

Thanks for the help guys. As far as checking the clearance, I understand what you mean by using clay, but since the lifters will "deflate" since they aren't solid lifters, how can you be sure that the valves are getting lifted the right distance? Seems to me that when I replaced my lifters, the lifters would compress slightly when hand cranking the engine. I might be wrong though. Is there some trick to keep them up all the way? At first I thought that you could put the piston at TDC and then push the valve down with a spring compressor and measure how far down it would travel, but I don't think the valves are at max lift at TDC. Anyway, it'll be a while before I start having to check clearances, but I'd appreciate some help. Thanks again.

------------------
Michael Black
Quantum Motorsports
Norman, Oklahoma

1988 Merc Cougar 5.0 HO, Ported and Polished E7TEs, 2.25" offroad H pipe w/ 2 chamber flowmasters, T5 tranny
New E/T!!!
14.626 @ 94.94mph, 2.194 60' time, a little better than last time. Keep in mind this thang is heavy (3590lbs) Finally 14s!!!!

Unit 5302 · 05-29-2001, 07:29 PM

What MAF are you going to run?

If you are SD, I don't think the car will run for crap with the X cam.

At .542/.542 lift 224*/224* the X-303 makes the F cam look puny.

It's way, way, too much cam for stock heads. The X cam is made for power up to 6500rpm, your intake isn't the best for it, and your heads won't come close. Even fully worked stockers won't make more than about 220cfm intake. That's with bigger valves and everything you can do to them. A decent port job with stock valves will probably put you into the 170cfm range.

Not to be the voice of dissent here, but even an F cam is overkill on stockers.

If you want the X cam, throw a set of serious heads on it. Or N20, since from what I've seen posted, it's a good nitrous cam.

QuantumMotorsports · 05-30-2001, 12:04 AM

I was thinking that the heads might be a problem. The only thing is, I want to stay cheap. What would you suggest for the best flow for the buck? I've seen people port stock heads and put big valves and they are able to get pretty descent flow #s, but you're right, you won't get the same flow as some aftermarket heads. Anyway, thanks for all the help guys.

------------------
Michael Black
Quantum Motorsports
Norman, Oklahoma

1988 Merc Cougar 5.0 HO, Ported and Polished E7TEs, 2.25" offroad H pipe w/ 2 chamber flowmasters, T5 tranny
New E/T!!!
14.626 @ 94.94mph, 2.194 60' time, a little better than last time. Keep in mind this thang is heavy (3590lbs) Finally 14s!!!!

Unit 5302 · 05-30-2001, 01:34 AM

To make the most of your combo, get the heads ported, some flow numbers and either use an B cam if you are S/D, or an E cam if you are MAF, otherwise, get a custom grind.

If your combo is matched, you'll do much better than with a cam that will make power between 2500-6500 an intake that will work between idle to 6000, and a set of heads that will flow well to 5500rpm.

You need a cam that will make power from idle to 5500/6000rpms. Have the heads milled for higher compression and better consistancy. If you have traction, I'd expect low/mid 13's with solid driving. You're about 500lbs heavier than a T-5 Fox, running low 13's would be the equivelent of a high 12 on a Mustang.

What were you thinking on the MAF sensor by the way?

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05-28-2001, 09:45 PM	#1
QuantumMotorsports Registered Member Join Date: Jul 2000 Location: Norman, Oklahoma, USA Posts: 597	Highest lift cam on stock pistons What's the highest lift cam you guys have ran on stock pistons without clearance probs? I want to run a motorsport X303 cam. I believe lift is .542 Does anyone know if this cam will work with stock pistons? Also, is anyone running a similar combo? Stock shortblock (or 306, 308) ported E7TE heads GT40 lower Cobra Upper 65mm throttle body 24# injectors X303 cam 1 5/8 equal length shorties 2.5" H pipe 40 series flowmasters underdrive pulleys If anyone has a similar combo, what kind of power are you making? or E/Ts? My cougar weighs 3500 and I will have 3.73 gears, it is a 5 speed. Any estimates on E/Ts?? I'm planning on building this engine this summer and have some of the parts already, I'm thinking hopefully mid to low 13s. What do you guys think? Thanks. ------------------ Michael Black Quantum Motorsports Norman, Oklahoma 1988 Merc Cougar 5.0 HO, Ported and Polished E7TEs, 2.25" duals w/ 2 chamber flowmasters, T5 tranny New E/T!!! 14.626 @ 94.94mph, 2.194 60' time, a little better than last time. Keep in mind this thang is heavy (3590lbs) Finally 14s!!!!

05-28-2001, 10:31 PM	#2
Idhomustang Registered Member Join Date: Sep 1999 Location: boise,idaho Posts: 220	If you are building you will not know until you check. Try and get .100 on ex. and the same on the intake side. This is plenty of clearance.Every engine is different even if made on the same day by the same man. Good luck, hope you get the ponies you need, to kick some bow-tie butt. Idaho Mustang ------------------ 393,9.5" 351W 830 Holley HP Victor Jr. Home made Cool Air Pan Pro Billet MSD

05-29-2001, 01:51 AM	#3
Mach 1 Registered Member Join Date: May 1999 Location: Georgia Posts: 3,866	yes, it will clear stock pistons. i have more lift, and mine clears. with 5 speed, low 13's should be no problem ------------------ 1993 GT/AOD '93 Mustang GT

05-29-2001, 09:36 AM	#4
2FastLX The Photoshop Guru Join Date: Feb 2001 Location: Mecca, Indiana Posts: 1,419	I am running a similar combo but with a GT-40 upper and F303 cam. I can tell you I was VERY close to the minimal clearance with this cam (.512 lift) and .030 shaved from my heads, which if you figure it is about the same as you will be. You should be close so I would check it with some clay just to be safe. It will definately be a 13 second car. With gears and traction you could come close to 12's but with a car that heavy it may take a 50 shot =) ------------------ Too much to list. Best ET on the car so far with stock 2.73 gears - 13.73@102mph Indiana Stangers Association Buy your parts here ICQ# 42269241

05-29-2001, 11:10 AM	#5
QUIN Registered Member Join Date: May 1999 Location: Chillicothe, OH. Posts: 1,289	i would not use 1.7 rr'ers either. have to recoment replacing the stock ones with a nice set of 1.6'es. Q ------------------ Quin, 87 GT,306,forged/cut pistons,edelbrock head\intak,steeda#18cam,1.7rr,MSD Blaster tfi coil,A9L,pro-m75mm,24#inj,accufab65mm,2.5"pipes,hooker headers,dynomax exhaust,3.73 gr,110 lph fp,180*therm,moroso cold air,ASP pullies, weld rims See my engine on user rides. I see your shwartz is as big as mine, now lets see how well you handle it!

05-29-2001, 03:56 PM	#6
86GT Sniffed too much n20 Join Date: Oct 1998 Location: Ont, Canada Posts: 1,018	Definitely clay the pistons to check clearance, its the only way to be sure. I've got an F cam with 1.90/1.60 valves, 1.6 RR, no problems with it.. Had .117" on intake, .118" on exhaust.

05-29-2001, 07:05 PM	#7
QuantumMotorsports Registered Member Join Date: Jul 2000 Location: Norman, Oklahoma, USA Posts: 597	Thanks for the help guys. As far as checking the clearance, I understand what you mean by using clay, but since the lifters will "deflate" since they aren't solid lifters, how can you be sure that the valves are getting lifted the right distance? Seems to me that when I replaced my lifters, the lifters would compress slightly when hand cranking the engine. I might be wrong though. Is there some trick to keep them up all the way? At first I thought that you could put the piston at TDC and then push the valve down with a spring compressor and measure how far down it would travel, but I don't think the valves are at max lift at TDC. Anyway, it'll be a while before I start having to check clearances, but I'd appreciate some help. Thanks again. ------------------ Michael Black Quantum Motorsports Norman, Oklahoma 1988 Merc Cougar 5.0 HO, Ported and Polished E7TEs, 2.25" offroad H pipe w/ 2 chamber flowmasters, T5 tranny New E/T!!! 14.626 @ 94.94mph, 2.194 60' time, a little better than last time. Keep in mind this thang is heavy (3590lbs) Finally 14s!!!!

05-29-2001, 07:29 PM	#8
Unit 5302 Registered Member Join Date: May 1999 Posts: 5,246	What MAF are you going to run? If you are SD, I don't think the car will run for crap with the X cam. At .542/.542 lift 224/224 the X-303 makes the F cam look puny. It's way, way, too much cam for stock heads. The X cam is made for power up to 6500rpm, your intake isn't the best for it, and your heads won't come close. Even fully worked stockers won't make more than about 220cfm intake. That's with bigger valves and everything you can do to them. A decent port job with stock valves will probably put you into the 170cfm range. Not to be the voice of dissent here, but even an F cam is overkill on stockers. If you want the X cam, throw a set of serious heads on it. Or N20, since from what I've seen posted, it's a good nitrous cam.

05-30-2001, 12:04 AM	#9
QuantumMotorsports Registered Member Join Date: Jul 2000 Location: Norman, Oklahoma, USA Posts: 597	I was thinking that the heads might be a problem. The only thing is, I want to stay cheap. What would you suggest for the best flow for the buck? I've seen people port stock heads and put big valves and they are able to get pretty descent flow #s, but you're right, you won't get the same flow as some aftermarket heads. Anyway, thanks for all the help guys. ------------------ Michael Black Quantum Motorsports Norman, Oklahoma 1988 Merc Cougar 5.0 HO, Ported and Polished E7TEs, 2.25" offroad H pipe w/ 2 chamber flowmasters, T5 tranny New E/T!!! 14.626 @ 94.94mph, 2.194 60' time, a little better than last time. Keep in mind this thang is heavy (3590lbs) Finally 14s!!!!

05-30-2001, 01:34 AM	#10
Unit 5302 Registered Member Join Date: May 1999 Posts: 5,246	To make the most of your combo, get the heads ported, some flow numbers and either use an B cam if you are S/D, or an E cam if you are MAF, otherwise, get a custom grind. If your combo is matched, you'll do much better than with a cam that will make power between 2500-6500 an intake that will work between idle to 6000, and a set of heads that will flow well to 5500rpm. You need a cam that will make power from idle to 5500/6000rpms. Have the heads milled for higher compression and better consistancy. If you have traction, I'd expect low/mid 13's with solid driving. You're about 500lbs heavier than a T-5 Fox, running low 13's would be the equivelent of a high 12 on a Mustang. What were you thinking on the MAF sensor by the way?