I have a bit of a problem.

I have SLP replica headers, which are identical and very high quality, which I was planning on installing my 95 Regal with the L67 swap. However, they will not fit, and the only option I have is to have the headers modified by a performance shop; Milzy Motorsports.

I was planning on using them, which is why I bought the 3.4.

My planned modifications so far are as follows:

Autolite 104'*
180 t-stat
3" downpipe with 3" catback exhuast
CAI

I was hoping that and the headers could allow me to run a 3.4. That, and I couldn't find a 3.5 pulley, and wanted more power than just the stock 3.8.

The question I'm posing to the L67 expert is, can I run a 3.4 with only the modifications I listed minus the headers? How big of a difference do those headers actually make?

If not, does anyone here have a 3.5" pulley they'd be willing to sell me?

Oh, and to add, this will all be tuned with hptuners, scanning for KR in the process.

There'* no way to say for sure you can run that pulley. I ran that size with a set of PEMs, free flow cat, and CAI with little to no KR. Had a GP here with that size pulley with headers, rockers, CAI, cat delete and had about 5* of KR. Headers help, but only as good as the most restrictive part of your exhaust, and your valves is that part. Rockers of a cam is what will really help. However, adding a cam or rockers do little good without headers.

So, it'* kinda like... play it by ear?

If you have no kr then you're good, but if you have a lot... do exhaust mods

right?

BTW, I'll be facing the same issues because I have a naturally aspirated bottom end.

There are different opinions such as port the top end. I'm a believer of open the exhaust. What goes in must come out. As for your NA bottom end, ya, your going to have to run lower boost because you have a higher compression ratio to start with.

In that case, I'll need to rent the zzp puller, unless someone here has one that they're willing to rent me for less than $30.

So nobody has a 3.5 pulley? I have a feeling that would be a lot easier to fit.

I would suggest you getting a MPS with a 3.5" pulley. That way you can switch pulleys without a puller. The 3.5" pulley seems to be the hardest to find.

I have heard that the reason for porting the top end is to reduce intake temperatures. I can certainly do the work as I have some experience porting, but the problem is that I need it to work perfectly before it gets to my house, which means the pulley has to be on, it has to be tuned, and it has to have 0 kr.

The problem there as well is cost, as those things aren't cheap, and I already have a 3.4 pulley. Know anyone who'* selling one?