When I was ruminating about my engine build, I decided I wanted roller-tipped adjustable rockers, and had no opinion as to roller pivots,or ratios.
I had read from various sources, that the Mopar 1.5 stamped arms might not be a true 1.5ers.I also read that the roller pivots put most of the spring pressure into just one or two rollers.
I wanted to run a hydraulic flat tappet cam, for several reasons. 1) the retro-rollers in '99 were more than I needed and very pricey, and needed block mods to work, and did I mention they were pricey ?But more than anything I was building a DD, and after having several solid-lifter set-ups in the past, I was kindof done with lashing. I just wanted to drive it.
I also knew that having lived with a stick-car since 1970, that missed shifts were inevitable, and I really wanted a SBM that would more than survive that. Plus I was done with short-shifting, to avoid lifter pump-up. My baby was gonna rev. So that lead to high spring pressures and very low lifter preload, which lead to adjustable arms.
I wanted the roller tips cuz I had just blown a major amount of the budget on the Eddies, and I didn't want to wear out the guides any time soon.Since I was buying arms I might as well buy 1.6ers, was my thinking.
I had chosen the Eddies cuz I wanted closed chamber heads, and I wanted to get away from that dog-leg factory exhaust port.
Then I also wanted to exploit the "tight quench" theory and max out my compressions.
Keep in mind that in 99, there were very limited head selections. I could have machined the snot out of Ma's heads but that would have brought the cost up to that of the stock Eddies, and I was still stuck with that ugly exhaust port, and now I might be married to whatever intake I stuck on there.So Eddies seemed the logical way to go.
I knew I wanted a torquey motor, so a big cam was out. But I wanted the big-cam pull at the other end. After some time spent searching, I found that there were only two or perhaps three companies out there that build cams to sortof address this idea. I wanted a short period advertised cam, with a lotof 050 time and as much lift as the Eddies would support. That's a tough call. It requires a very fast rate of lift, and very generous springs.So I found a guy that I thought knew what I was trying to achieve. He made his recommendation.
Then I got side-tracked, and greedy, and stuck in the 292/508 cam. I knew right after the break-in that I had made a mistake.You know that cam made a heck of a top-end run. But it was a slowmobile til it got going. So I bumped up the compression with thinner headgaskets. Still soggy. So I messed with cam timing. But no change. So I installed some 4.30s. Now we were talking. 'course I no longer had a DD.
I pulled the cam.
I went back to the drawing board. I remembered what that cam-guy had recommended. I installed his itty-bitty 2430 cam. 223@050! Are you kidding me. However I had made up my mind that I knew chit about cams, and would have to trust somebody who did.That cam is a 276/284/110 advertised. Pretty teensy I thought.
I stuck it in, and reusing the felpro .039ers. I was prepared to test-drive that beast around the block, come back, and pitch that little guy.
Well surprise,surprise. That little guy was capital B,Big on performance. It was everything the cam-guy said it would be.But the big surprise was that it didn't know when to quit. It just pulled to no end, 5500,6000,6500,6800. I quit.
Well that cam, I expected to be in there forever, but around 2004, the beast dropped two lobes into the pan. So sad.So I called that same cam guy. After a little discussion we moved up to a 3037 cam. This is a 230@050. Just a little hotter.This cam lost a bit on the bottom, but I had had so much before, that after a while, I got used to it. But the midrange was terrific! And again, it didn't know when to quit.Since I had missed a few shifts with the earlier cams, I knew the engine could rev, and survive, deep into the 7s, so I decided to push it a little. I quit at 7500. It was still pulling. Now 7500 with 4.3s is 100mph in 3rd gear/1 to go.Fast enough I said.
Out came the 4.30s, in went the 3.55s, and I already had the GV by this time. The 2430 cam had registered some phenomenal mpgs with a double O/D. But I knew this cam was not gonna be able to pull that combo(1.97final drive). So now with the 3.55s and .78 O/D the final drive is2.77. She pulls that easy enough, requiring just2200 to vacuum peak which makes 64 mph.
-So finally, here's what has worked for me; 1.6 arms(roller tips only), Eddies, .035Quench, a fast-rate cam,designed for the.904 lifter,.020lifter preload, Static compression right around 11/1. a Dcr around 8.7,a starter gear of 3.55 x 3.09 =10.97.
I offer this cuz I spent thousands of dollars and hundreds of hours, figuring it out.It may not be a DD anymore for some guys, but the diaphragm clutch makes it so for me.It burns 87E10 at WOT with full-power timing of 34*, +/-2
-It has gone 93ish in the 1/8th, using the GearVender as a splitter. First,1od,Second, 2od, equals 93@7200,with 4.30s.Once out of the hole, the tach drops about 1400 at the shift. Shazzam!!
It's not real quick tho, with street suspension. 60fts are 2.00 to 2.24 with 325/50-15DRs, and the only successful ET I have is 7.92@92.9x@3650 total lbs.
-Summary
--Long story short those 1.6 aluminum arms,roller tips only, purchased from the Chrysler dealer in 99, are still on there; and the heads have never needed guides.After the cam break-in, I readjusted the preload, and in the 11 years since, I only recall 2 readjustments, one of which was a test. 1/4 turn preload is not enough.
OOps I think I got sidetracked. I might be in the wrong thread, again.
But no way I'm gonna erase an hour and a half's worth of typing, sorry Numax.
So for you, after reviewing your posts, about the only thing here that could be useful,to you, might be the summary.