Is it worth the extra money?

[281pony]

im building my 306 with edelbrock rpm heads/intake both gasket match ported by a machine shop. i also have a cam thats pretty borderline streetable, so im a little worried about lowend punch.

my question is, i have limited money right now and need to do a couple more things. first is sell my pro-m mam and 19# injectors for get 24's, and im considering longtubes now.

is it worth the lowend gain for me to find the money for longtubes/new h-pipe?

i know its been covered before, i searched under some longtube posts. the result i got out of it was "pain in the ass to install, gain lowend". well how much lowend can i expect and im installing them on my engine before dropping it in so that wont matter much.

exact combo is: dss pro bullet 306, 282hr cam, edelbrock rpm heads/intake gasket match ported, 70mm tb, 77mm maf, 1.6 rockers, march pulleys, ect. current exhaust is bbk 1 5/8 equal lengths, offroad h-pipe, flowmasters.

 

[DMAN302]

If not only for the sound then yes to compliment the now much increased exhaust flow..will help with your lower end torue.

 

[281pony]

ok, sound is always a plus. just dont want it to be a dog on the lowend.

i should probably stick with a 1 5/8" still since i just have a 306, dont you think?

 

[Michael Yount]

A couple of months back MM&FF did a test of 4 different headers on a modded 347. They compared unequal shorties, equal shorties (both 1 5/8" primaries) against 1 5/8" and 1 3/4" long tubes. There wasn't 3 HP difference at peak between any of them. But they showed almost 30 lb-ft more torque at 3000 rpm with the 1 5/8" long tubes. The 1 3/4" also showed more torque compared to the shorties, but not as much as the smaller long tubes.

They didn't show numbers below 3000, but I suspect the strength continued or was even greater down low. If that test is indicative, I'd say the long tubes would be well worth the bottom end gain. Just don't get carried away with too large a primary tube size. Up to 300HP, 1.5" primaries won't hurt your peak, but will help bottom end even more. When you start to move above that level, you probably need 1 5/8ths. Any bigger than that is only for really serious hp levels out of a 302.

Just goes to show you how clueless they are when it comes to most of their tech articles - not only did they not mention the HUGE torque gain down low, they didn't go back and rerun the test at a lower rpm to see what other differences they could uncover. It's beyond me...

 

[281pony]

wow, 30 pounds. hell that is worth the money definately.

thanks for the info michael. i need to get a subscription again to some type of mustang magazine.

 

[ratrapp]

they're worth it but i don't think you'll be able to put the headers on and drop it into the car though.

 

[281pony]

yeah i was thinking that would be a pretty severe angle to tilt it. if that doesn't work, i can just as easily put on some headers after the engine is dropped in.

 

[Michael Yount]

Lay the headers in the engine compartment while you're lowering the engine - once it's down low enough, hook them up - and drop it the rest of the way in. It's done all the time that way.

You don't need a subscription - I usually pick up that kind of stuff while waiting in the mag dept. for my wife to finish shopping at WalMart.

And remember the most important part of my previous post ---"If that test is indicative,..."