Nassar

Hi All,

Going through threads with regards to long tube headers and fitment issues, I have decided to go for block huggers. The car is 1976 corvette with GMPP 385 crate. It comes with Fast Burn heads. Sanderson makes the CC1DP with 1-5/8" tubing. The McJacks 13425DPORTare 1.7.5" tubing.

What are your thoughts/recommendations?

Thanks all.

http://www.sandersonheaders.com/Sand...eader-Set.html

http://www.vetteheaders.com/servlet/...orvette/Detail

MelWff

I wouldnt use block huggers, but if you want to I would go with the second choice because they are specifically for corvettes.

jb78L-82

I have McJacks on my 78 L-82 4 speed and love them for the street. I have had long tube headers on other cars in the past and just don't feel that they are worth the hassle for the street, thus the Mcjacks choice which are a perfect fit dimensionally of the OEM cast iron exhaust manifolds in a shorty header. I specifically used the McJacks since I wanted to hook an OEM type dual 2.5 inch exhaust to the headers with no modifications and no clearance issues. road or engine. If you are planning to use an OEM type dual exhaust, I would spring for the money for the McJacks, if not, the Sanderson would probably work fine for less money. I also don't think that there is much if any HP loss using the shorty's versus LTH's.

I just ran my pretty stock L-82 on the dyno with the McJacks, true 2.5 inch duals, and Monza Turbo mufflers with a result of 233 RWHP which I was pretty happy with. Another forum member with a 78 L-82 with an Edelbrock Performer intake, a cam of unknown origin, and a magnaflow true 2.5 exhaust with stock OEM exhaust manifolds did 248 RWHP. My assumption is that the McJacks added some HP versus his combo. I run BBK shorties on my 1994 Mustang GT convertible versus the ford OEM tubular exhaust manifolds and the BBK's definitely added some power versus the OEM ford manifolds.

Hope that helps.

trainor

I did McJacks and never looked back. Best product and a awesome guy to deal with, a real pro.

Tim H

You looked at all the header threads and decided on block huggers? REALLY????
If you can find a better and cheaper set that fits with "0" fit issues like the Summit brand let me know!

terry82

mcjacks headers look great .they are made for the corvette .but they have the corvette tax on them .a lot of money, but if they are the best you wont be unhappy.

Rotonda

I would also consider the following:
http://www.stans-headers.com/tri_y.htm
These are tri-y design and are considerably less bulky than the 4 tube design; these are specifically designed for your C3; Stan's makes a spectacular quality heavy gauge product; and they come with a ball and socket mount to the exhaust.

Do some searches.

bluedawg

If you decide to go long tube, hooked comp fit mine with out issues.

ptroxx

I have the Sandersons on my zz4 with no issues, I used hugggers because my front end sits very low and was worried about hitting the flange...
I dont recommend using them without a gasket like the suggest...
Plus they are made in the USA about 60 miles from my house...

jb78L-82

There is nothing wrong with blockhugger or McJacks headers on a street car. Unless you plan to spend most of your time above 5,000 RPM the difference in power is negligible! In fact, shorty headers make better power in the low to mid RPM ranges than traditional LTH's-Check out Sanderson's website-they do a nice job of explaining the difference between shorties and Long tube headers. The clearance issues for LTH's is not just in the engine compartment but also road clearance. LTH's collectors generally sit lower than the OEM pipes would and reduce road clearance! Check out the pictures above-notice that you cannot see the pipes coming down from the engine.

blackbeauty74

I too have Mcjacks on my BB and I like the quality and fit. Also I got a great deal on them from a forum member.

Tim H

Sure Sanderson show positive results with shorty headers, they sell them!
There is no clearance issues in the engine compartment with long tube headers and I can't even see my headers under my car so no problems underneath either.
Shortys are not even a step above a stock manifold, they are not tuned length like long tubes, they are made for street rods.

jb78L-82

Sorry we disagree but that's the beauty of the forum and what makes the world go round

My experience with LTH headers in the past on SBC's, my current experience with switching out the OEM cast iron manifolds for the Mcjacks on the 78 (no other changes when I did the header install), and a similiar experience on my 94 Mustang GT with the BBK shorties in place of the Ford OEM tubular exhaust manifolds (no other change for that header install either-just the headers, NOT the exhaust system) does not bear out what you are saying.

One of the reasons that I did not go with LTH's on the Mustang (along with the positive results with the McJacks on the 78 and researching the subject) was that the Mustang forums were equally divided on the street benefit to the LTH's on the GT 5.0 for mild modified engines!

Do I think that LTH's will produce the best increased HP versus OEM manifolds/Shorty's? Yes but to me it is not worth the 5-8 HP increase over a Shorty for a street car with mild mods. If someone has a 500 HP engine that they are building for maximum HP, then I would go with LTH. Just my opinion.

http://www.sandersonheaders.com/Lets-Get-Technical.html

Ganey

Those are tubular manifolds. If you must have shorty headers, then look for this design that comes out from the head & the outsides V down.
http://www.jegs.com/webapp/wcs/store...d=&showValue=1

jb78L-82

Yes you are technically correct! Two other anecdotes:

As mentioned above, the McJack's install was done on my 78 L-82 4 speed with zero other changes either to the exhaust or engine. Just the McJacks added to the already installed 2.5 true duals with Monza Turbos. After the install, the exhaust sound was MUCH louder for the McJacks only. That tells me that the exhaust flow increased dramatically.

#2 Forum member Karaol who accompanied me to the dyno run below has a 78 L-82 4 speed as well with a cam, Performer intake, and Magnaflow mufflers with 2.5 inch duals, and an open aircleaner K&N with NO headers (OEM manifolds) versus my setup above with Roller tipped 1.5 comp cams rockers and a K&N airfilter in the OEM dual snorkel air cleaner. His engine produced 248 RWHP versus my 233 RWHP. I have to believe that the only 15 HP difference is because his engine is NOT running some type of header/tubular exhaust manifold etc. 15 HP advantage for an intake and cam versus my OEM internal components? Maybe, maybe not-you decide! Just food for thought! Not hard facts here!

Tim H

So now were sayin running stock manifolds produce more horsepower than headers?
I give up in the thread, you might as well turn the lights on and say it just got darker.

jb78L-82

Nope-Not saying that at all. Maybe someone else can explain to Tim what I am suggesting!

ptroxx

Good luck with that. Tim has owned 82 cars and counting and thinks what ever he says is it. Good thing we don't have to listen to him other wise we maybe going thru cars like he does.

I have lowered my 77 close to 2,5 inches and I hit pebbles in the road with my oil pan/trans pan. And I know if I went with lth I for sure would be hitting them too.
Ok it's not that bad but I can't go over any speed bump without the chance oh hitting.

I love my sandersons On my stockzz4 dynoed at 265 and was. Very happy with that number well. Was. Getting ready for new cam and OD trans ASAP

See she sits low.... about 3.5 inch clearance from ground to exhaust..

terry82

would love to see the dyno results to prove long tube short tube .but we cant rely on the makers of the headers to give fair results.my idea is if i want the best flow at high rpm go with long tube .mostly street shortys are fine.

ptroxx

I found this on another site, grantes its not a corvette but gives you an idea... its an 89 trans am...


Dyno Test Long Tube Versus Short Tube

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I had a set of custom short/mid tube headers made to fit my car and allow me to use the exhaust termination boxes. Here are the results from the engine dyno.

The test was against a set of 1 3/4 inch long tube headers versus my chassis fit custom made 1 3/4" short-mid tube length headers. Joe Sherman could have wrote the script ahead of time on the results.

Basically my headers were down to the long tube headers at 3500 rpm 438tq/292hp to 406tq/271hp. From that point on the custom headers started to make a comeback and at 5000rpm the long tube headers were at 469.6tq/447.1hp and the custom headers 462.2/440trq. From then on to 6500rpm it was somewhat of a seesaw. The longtubes averaged 1.4 more horsepower over that span versus my chassis fit custom headers.

So with my 4000rpm stall I don't think I will be giving up much power at all for the rpm range I will be running down the track. Peak torque was at around 5000rpm and peak horsepower was at 6500. Shift point will be at 6800rpm as that is when the power starts to nose over.

Best dyno numbers with the long tubes was 526 horsepower at 6500 and 471 torque at 5200rpm.

Best dyno numbers with the short tubes was 524 horsepower at 6500 and 466.5 torque at 5300rpm with the same conditions.

We switched to Mobil one and let the intake manifold cool off but kept the oil hot and we managed to squeeze out 535 horsepower out of the short tube headers. This motor only likes a total of 30 degrees timing.

So bottom line above peak torque there is virtually no difference. Below peak torque you start to give up some power and torque. A lot of us have to much power down low and are trying to kill torque. So let's say I'm quite happy how things turned out. When this motor goes in my car I will loose very little power from the dyno with the these headers. The power loss will come from the accessories and the drive train.