Don Terrill’s Speed-Talk

Im surprised no "Expert" has recommended their "speed secret" Rotella oil......Im a big fan of Rotella......in my diesel pick up :) Use of diesel rated oils was big right around 2007 when the API oil specifications put limits on ZDDP for passenger car oils and the cam lobe wipe-...

The big question to ask is "what additive pack does a break in oil have, that a regular oil doesn't, that will make a difference during the break in period?" I've never seen any solid tests or studies that prove a certain additive pack helps with break-in. Flat tappet cams require adequate...

I run a SBC 383, about 450HP. Most here would not consider it radical, but it has plenty of vacuum for power brakes and no issues running the A/C compressor. Ideally it would have some kind of solenoid or servo to bump up the idle speed a tad when the compressor kicks on (it is carbureted), but othe...

Is the mechanical/vacuum advance locked out? If so then that explains it. You need a start retard box. MSD used to make one but I still see quite a few floating around on ebay. https://www.summitracing.com/parts/msd-8982

Ok,, read the 'reduced TQ' bit. And realise that with a full system after that , its not realistically going to be increased HP. Deliberatly making the h pipe smaller?,,, save the welding wire, time and pipe. Once you kill a harmonic its gone. Put the T-box (not my personal choice) or H pipe at ide...

I did a little more research on Pipemax. It seems whatever it gives you as your ideal collector length (4th harmonic), it will also tell you to put your H pipe right at the same spot. This makes sense for a full exhaust system, the H pipe is an easy way to get some sort of cross sectional area incre...

Perhaps the most important aspect of H-pipes is that to my knowledge, no one has ever reported more noise or less power when using one. :-k I think that's probably the best and most to the point lesson on the H pipe that I've ever heard. :lol: Now if I could just the part of my brain that always as...

Pipemax is one program that suggests H-pipe locations. Those are related to the "optimal" collector lengths in the sense that the full-diameter cross-over looks a lot like collector end to the pulses. The same way the optimal collector length is not zero, the optimal location of the H-pip...

Since the replies have slowed down I'll go ahead and say thanks to everyone for the input. I think I understand better what the needs are in terms of overall design. I do want to run an H pipe now. I'd like to talk about optimal placement. I know most cars place it where they can, usually after the ...

Another option...spintech can make you a muffler in about any configuration you want. I had them make me a dual 3" in/single 3" big case muffler for my suburban because i needed something relatively quiet and drone free that would fit into the existing muffler spot and connect to the exis...

In response to the recommendations for running a single large box, I agree that it would probably be the more efficient way to do things but I'm not so sure that will work with the layout of things underneath the truck. If there was a single large box it would have to live right behind the transmiss...

To address the collector/pipe size recommendations, I would agree that my engine would probably do best with 2.75, just based on what other people are saying about their engine/exhaust combos. The headers I have use 3" pipe for the collectors and I have plenty of 3" pipe that I already own...

That is almost identical to what I put on my TransAm. Except I had 2 3/4" pipes out of the header and 3 1/2" after the wye going into the muffler. Worked out quite well. I made my own termination boxes out of oval tubing. I believe I've seen the ones you made back when I doing a lot of re...

A couple of comments. These aren't informed by much practice, but I've been thinking about the problem for a little while. So take these for what they're worth. I think the proposed setup has a lot going for it. It combines the pulses and reduces the cross-sectional area a little bit at the tail pi...

I had a similar exhaust on my old F100. It exited under the passenger side step. It was *way* quieter than the old system exiting out the back; I'd guess the pipes themselves transfer a lot of noise to the vehicle, and by making them shorter there's less to transfer. The short pipes didn't have the...