Going to preface with: I am not currently considering long tube headers. I understand they are more optimal, but it's just not what I want to do to my car and spend money on at the time being.

My valve stem seals are leaking so I have the top end torn down to get into that job. While I'm tearing into things I'm thinking about swapping the factory headers for a set of Hooker super comp block huggers. I have them on the shelf and they seem reasonably close enough to work with the factory Y pipe. I have an '87, L98 with 113 heads, but not the raised D port of the later aluminum heads. Motor has a large port intake/runners with ported plenum, 52mm TB, and 1.6 ratio rockers. I am going to keep the EGR and emissions for the time being, but I can cut the tubes off the factory headers and weld them on the hookers. That all being said I have a few options so I'm curious about opinions on whether I should:
A. Port factory manifolds to be less restrictive, leave everything else alone
B. Install hooker headers I have on hand and transfer emissions equipment
C. Leave it alone

One other question regarding block huggers, there seem to be "angle plug" and "straight plug" variations. The angle plug headers seem to have the center two header tubes in come into the collector closer to the block, and the outer two tubes on the outside. Straight plug versions seem to have this pipe arrangement reversed. The hooker super comps I have seem to be the straight plug orientation. If anyone has block huggers on their early C4, how close were the collectors to fitting with the factory Y pipe, and how accessible are the plug wires? If anyone has pictures, a picture is worth a hell of a lot.

Thanks!

 

I read somewhere that shorty headers are no better than what is from the factory. I did not look into it further, You may want to do that so you do not spend foolishly.

 

C. Leave it alone.

Shorty headers are notoriously terrible. There might be a few ponies to gain, but it will likely take more effort and trouble than it is worth. Especially since the the L98 is a lower RPM torque oriented engine and shorty headers usually only provide a slight gains in higher RPM range. Shorty headers or block hugger style headers aren't really a performance piece, they are really designed to solve fitment issues for engine swapped cars. Or, they are an alternative to oem style manifolds if you can't find a set that work with a particular vehicle.

Problems/issues you might face:

Broken exhaust stud/bolt, removal/repair
Y pipe needs modification
Spark plugs harder to access
Might need different plug wires, or a mix of different style of plug wires
Melted plug wires, or the need for ceramic or heat shield boots on the wires
Exhaust leaks
Under hood temps rise
You spend a lot of time/money/effort troubleshooting just to find out that the headers hurt performance and/or you don't like the sound.

 

Thanks, I like this option. I'm just stubborn and sometimes like to push into things that I shouldn't. My life will be one helluva lot easier if I don't touch the headers at all and I appreciate the feedback.

 

stock headers go from 160cfm at tubes to 115cfm at collector and thats ported at collector . A good shorty header will flow csa x 115. Most after market headers are 1.625 will flow around 200cfm. In most cases i would agree that shorties don't help. In this case i think they will. Hedmen full length headers fit nice

 

There is improvement to be had with the manifolds, along with porting. You didn't mention the rest of your exhaust, if it's stock and you still have cats I doubt you'd be accomplishing
anything with shorty headers, and I suspect it's choked up with your mod list as it is.

 

this is what the stock exhaust manifold looks like at collector.
these measurements come from a 84. but all these style exhaust manifolds look like they are pinched off the same at collector.
stock csa .88.6. 88.6 x 115 = 101.89 cfm
ported stock csa 1.03. 103 x 115 = 119 cfm
next restriction would be cat and mufflers