[97mustanggt]

bhead

[Mach Boy]

I was agreeing with you, but extending the answer. Whenever you shorten the runners you gain HP but lose TQ.

[97mustanggt]

oh yea cuz i saw an earlier comment saying that u gain tha horspower and dont loose any low end

[shadow98gt]

i have Complete B-heads for sale... PM me if your interested!!

[acidtonic]

You dont *always* lose low end unlike the commonly held beliefs.

Nazman can port the intakes for less than a grand if I remember. I dont want to quote his prices but I remember hearing 700.

He has before and after dynos proving it actually gains a tiny amount of low end until the peak where the first(before) stops and the second(after) keeps going up and out another 20-30hp with a higher peak.

Basically when it feels like your motor is running out of steam at around 6200-6600 or so the short runner will allow you to basically keep reving for a bit longer before it wants to fall off.

[Mach Boy]

Yeah basically 7000RPMs is where the power goes to with a ported short runner intake. This is a link to Naz's site where it has the dyno graph of a ported intake to a ported short runner intake and the torque dropped by a little over 6rwtq. But the gains in HP are greater than the loss in TQ and racing is done in the upper RPM band anyway though. Oh but before you go and order one find out if he is behind on his orders still. Last I heard, he had some health problems and family problems he was going through. So it may be a while before you get it.

Nazty Performance -Your Source!

[acidtonic]

Thanks for the backup. He pm'ed me a few charts over at Corral which showed gains down low from 0-5hp and some torque as well.

I think that was just for a short runner but not ported. I think the porting is what hurts low end more.

Didnt hear anything about his health. Wish him the best.

[Mach Boy]

It's the shortened runner length that hurts the low end TQ. Here's a link to his ported intake (not short runner). There are gains in TQ with a ported intake.

Nazty Performance -Your Source!

[acidtonic]

Originally Posted by Mach Boy It's the shortened runner length that hurts the low end TQ. Here's a link to his ported intake (not short runner). There are gains in TQ with a ported intake. Nazty Performance -Your Source!

Thanks for the correction and the link. I knew my memory was telling me something along those lines

[dcook_14]

Originally Posted by Mach Boy There's also a difference between the Mark 8 B heads and the 96-98 Cobra Bs. The Cobra Bs are better.

Nope. Mark VIII heads and Cobra heads are the same. The Cobra's intake cam has a little longer duration, that's why the cobras have a little more power.

[acidtonic]

Originally Posted by dcook_14 Nope. Mark VIII heads and Cobra heads are the same. The Cobra's intake cam has a little longer duration, that's why the cobras have a little more power.

Wrong. See side by side pics here with an explanation. Small but when going NA every little bit can help.

All B heads are not created equal - Corral Forums

[dcook_14]

I've read that several times before, and I guess technically we're both wrong. It doesn't say there is a difference between mark heads and cobra heads... it says that there is a difference between early b heads and later b heads. I'd like a little more proof of this, but for now this is all I got. Post #4 the guy says the heads from his later mark are the PN xxxxxAD which are the same as the cobra heads. So I guess yeah, early mark heads are different from cobra heads but the newer mark heads are the same.

Doesn't matter so much to me being FI, but I agree N/A you need to squeeze everything you can out of them. But if you're getting the older b heads ported anyway, which most people would, you could have them re-work it to make it flow like the later b heads in the cobras and later marks.

[acidtonic]

Agreed. I'm more interested in at least passing on the knowledge that something could be different and to account for that if your build is more serious.

[dcook_14]

Yeah there are a lot of misconceptions about 4v heads and the whole mark VIII vs cobra heads is a big one. Good link!

[acidtonic]

Speaking of these home brew B head intakes, here is a good thread with pictures and some write up.

b heads direction - Corral Forums

A few others have asked about how to get a hold of Nazman so here is a link to his site advertising his services. Over on Corral he is a well respected guy and many recommend his work.

Nazty Performance -Your Source!

Also search up on the Sullivan B headed Intake. That better come out soon though because it's starting to lose interest with such a delay.

[dcook_14]

What's the difference between the 96-97 cobra head and the 98 cobra head? I called MAC Performance and questioned them on their headers for these cobras, and they said that the 98 is different and they make a different header specifically for the 98 cobra.

[acidtonic]

96-97 used aluminum IMRCs and 98 had plastic ones which were harder to gum up and being plastic they were a bit better for heat dissipation.

I'm not sure about the headers but one thought is 96-97 had the older fuel pump mounting setup compared to 98 when it was a bastard year for the switch to returnless setups.

Basically pre 98 were the old style,
98 had newer style mounting with old return style pumps,
and 99+ had the newer style mounting with new returnless fuel systems.

Remember that return style fuel setups are better for everything except emissions.

My guess is something might be different with the fuel tank which could change the rear exhaust mounting. Making the headers shorter to slide everything towards the front for more clearance? Thats a guess but I really dont know why 98 would be special for just the headers and not anything else. Only way it stands out is the fuel differences along with IMRCs and of course the deleted dash clock. I bet it's that

Anyone else hear of 98 being special? Never heard about that myself.

[97mustanggt]

i so envy your quarter mile acidtonic seeing its all stock

[acidtonic]

Originally Posted by 97mustanggt i so envy your quarter mile acidtonic seeing its all stock

But its not stock, I've pulled a tremendous amount of weight from the vehicle, and shed weight wherever possible. I also weigh 160 dripping wet being a shorter guy at 5'11. I mean the car is gutted man, no doors, no center console, no carpet, no deadening behind the dash. You can hear the diff working and its loud. You cant talk on the phone its so loud in there just cruising at 60mph in 5th. All road noise.

I used to answer my phone and quickly roll the windows up to talk. Now it does absolutely zero and rolling them up just stops the wind noise but you still cannot have a conversation without yelling. I personally dont care and love the extra attentiveness it brings.

Besides 12.68 is freaking slow for how rough the car is right now. I'd still rather go 12.68 with a full interior with carpet and such. That just requires more money than I'm willing to spend right now. Far cheaper to pull weight and use the power you already make.

The front tires were bumped down to a 225, I had just changed the oil and replaced the air filter right before the run. I also had better traction than the tires I'm running now and a good day at the track.

It all adds up. I'd say the car is probably an average 12.8 to 12.9 car and I got some good numbers on a good day with many things lining up to help out that time.

Also the B headed Cobra has such a pathetic low end that removing the weight really makes a difference because its not only less weight to move, but more importantly less weight bogging the motor. So it can spin up to where it *does* make power much faster since there is less weight in the bog zone (0-3500 rpm) slowing it down.

And having the low end come back without switching gears I can still go 0-45 in 1st, 45-80 in 2nd and 80+ in 3rd, which is perfect for daily driving and fuel economy. I do want 4.30s at least though when I get around to it.

I think with some 4.30s or 4.56s and a couple bolt ons she will run much better than a 12.68 if I keep up on the weight.

[97mustanggt]

dam no joke on tha weight reduction, yeah with some bolt ons, who know what you can pull off...i agree i hate tha low end, if we are to race from a roll, at what rpms is our prime what will give us tha edge?