Head And Cam Questions

[mustang8998]

I have brand new set of GT40Ps, all ready to bolt up. I took the old heads off today and was looking at them, to see if anything had ever been done to them. Thing of it is, I can't find the casting number on them. I looked everywhere, but don't see it. From a little research, the numbers should be on the block side, in the unmachined area. Correct?

Next, I pulled the cam. The numbers on it are M6250, E or F (can't make it out), 303. So how do i tell, if it is an E, or an F? I measured the lobes (with calipers) and came up with 1.400 on the small end and 1.715 on the big end.

That also brings me to the question, of what is THE best cam, to run with the GT40Ps. If I can figure out what cam I already have, it would be nice to know if it is optimal, for the heads.

Thanks!

[93hulk]

Hey Jeff I looked at my e-cam i have laying around and has M6250 E-303 and it also has I would like to say a part number right above it 970722. Hope this helps. Im running an x-303 with my 40-p's. So far the car has went 12.83 @108 but has been 109. With a best 60 ft of 1.91.

[mustang8998]

Thanks Mark. There was another number there too, but I didn't think to post it. It is 320740. I couldn't find anything that pertained to that number.

[mustang8998]

Well.........after a little research, the heads I took off, turn out to be World Products Winsor J/Rs. So now the big (head) question, which heads will be best. J/Rs or, GT40Ps. Off to do a little more research. :rolleyes:

The Ps are brand new castings, with all the good parts. The J/Rs, will need to take a trip to the machine shop.

How about it, you F/S guys. :dunno:

[mustang8998]

Bump. :o

[Timido]

My old F/S car with the gt40P's explorer intake stock cam bone stock shortblock went 12.40's

A car to compare it to was 331Twistedwedges coupes old motor combo.

Windsor Jr heads Holly intake stock cam I think it ran mid 12's also. I cant remember.

I think it would be kinda a toss up I cant tell you one head is better than the other. I drove both cars on the street and the track and I couldnt say one was better than the other.

[331TwistedWedge]

tim your combo was quicker back in the day ... i ran the systemax intake with the windsor jr heads (no cam) ... not much traction (bf goodrich drag radials) and used to trap 104 on a good day ... im NOT a big fan of the windsor jr heads ... it was a combo i had back in 2000 on a 302 - did not like it ... i would run the gt40p heads and cobra/explorer intake with a decent cam ... there is more power to be made ...

[Timido]

With my stock shortblock I dont think the trap speeds were much different 103-104 Now when I had a purpose built 310 with lightweight stuff the same heads and intake made a BUNCH more power. Try 50hp+ Hp and 50+Lbs of torque at the wheels.

[331TwistedWedge]

tim i think we hit 12.90's on a good day with the bf goodrich dr's, i didnt care for that combo - but again i was new to the aftermarket world and could have done more for my car to get it to run ... via: slicks, suspension, more gear (3.55's) and such ........ i dont know, maybe its a toss up on the two combo's ... i guess either one will get the job done if you're looking for mid 12's ...

but come to think about it, my '87 trapped 105 with stock ported heads and a trick flow track heat intake ... love the speed density car when it was the silver stocker ... i used to beat combo's out there, isnt that right larry :lol:

[mustang8998]

Rick, I ran 12.95@105. This was a cool day, no air filter. Took off the belt, went 12.73. This combo dynoed 260/302, when it was a 5 speed.

My VB Garage. (http://www.stangbangerz.com/forums/vbgarage.php?do=view&id=234) Look at this. All is accurate, except the part about stock heads. As for the cam, it is either a E or F (the letters are worn).

I'm also adding, Cobra MAF, 24# injectors, long tubes, electric fan. I'm thinking about a Power Pipe (has stock meter and elbow now).

If you think any more info would help, just ask.

[mustang8998]

I still cannot find any good info, to help me figure out, what cam this is. I know it is either an E, or F.

I tried FRPP's tech line, they are only availible mon-fri, bankers hours. :mad:

Mark, do have a way, to measure the lobes on your E cam? Then I can compare the two.

[Jeff88coupe]

Well..using your ruff lobe measurements you get a lobe lift of .315" x 1.6 (rocker ratio)=.504" lift Isn't a E303 cam .498 lift? As far as which head is best...agree with Tim..it's a toss up. If the gt40p's are all ready to put on the motor with good valve springs already on them....I'd put them on. If it is a E cam you have I'd stick with it. You should be able to make 270-280rwhp with stock gt40p heads.

[chuck8950]

Yep the E303 is a.498 lift.

[mustang8998]

Well..using your ruff lobe measurements you get a lobe lift of .315" x 1.6 (rocker ratio)=.504" lift Isn't a E303 cam .498 lift? As far as which head is best...agree with Tim..it's a toss up. If the gt40p's are all ready to put on the motor with good valve springs already on them....I'd put them on. If it is a E cam you have I'd stick with it. You should be able to make 270-280rwhp with stock gt40p heads.

This is confusing me Jeff. My math was the same as your's, .504 lift. The E is .498, F is .512. I'm almost dead in between. I don't think the cam is wore out either, seems OK. :mad:

[Jeff88coupe]

I bet you have a E cam...it's hard to get dead on measurements of a cam lobe with just a caliper.

[mustang8998]

So, Jeff, if we are right (on E cam),is that an "optimal" cam, for the P's?

I've even thought to put the P's on it, dyno and run it. If it has hurt my previous HP, or ET, I'll get the JR's done up and try them.

[Pitviper1996]

or sell em to me:)

[mustang8998]

or sell em to me:)

One set, or the other, will be for sale. IF I ever figure out what I'm going to do. ;)

[dedpedal]

One set, or the other, will be for sale. IF I ever figure out what I'm going to do. ;)

Jeff, if you have a block that you can put the cam in and a dial indicator, you can measure that cam much more acurately. I have a shortblock on a stand that is cam free if you want to make the trek down here.

[mrstang-gt-46]

want to sell winsor jrs? if so how much

[331TwistedWedge]

just watched a kid last night run 12.40's at 108 on a slippery ass track, using a stock explorer (junk yard) motor & a stock mustang cam ... pretty impressive :bigthumb
probably has 12.20's in it on a hooking track ... he's on the stangbangerz board, but i forgot his user name (wild strawberry metallic coupe) just like mine ...

i like those p heads better than the windsors jr's ... i never trapped that hard!

[mustang8998]

Jeff, if you have a block that you can put the cam in and a dial indicator, you can measure that cam much more acurately. I have a shortblock on a stand that is cam free if you want to make the trek down here.

Do you have a dial indicator too? I could do that, if you do. :bigthumb

[mustang8998]

just watched a kid last night run 12.40's at 108 on a slippery ass track, using a stock explorer (junk yard) motor & a stock mustang cam ... pretty impressive :bigthumb
probably has 12.20's in it on a hooking track ... he's on the stangbangerz board, but i forgot his user name (wild strawberry metallic coupe) just like mine ...

i like those p heads better than the windsors jr's ... i never trapped that hard!

I think I'm going to go ahead, with the Ps, since they are all ready to go. I'll hold on to the J/Rs, incase I don't like the Ps. I'm getting a little anxious to get it going. Just trying to get it right the first time. ;)

[dedpedal]

Do you have a dial indicator too? I could do that, if you do. :bigthumb

Ill get jeff lange to come down with his.Want to do it one night this week? We'll be on vacation next week.

[mustang8998]

Ill get jeff lange to come down with his.Want to do it one night this week? We'll be on vacation next week.

Sounds good to me. I'll shoot you a PM. :bigthumb