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Learnings from revamping engine

2K views 5 replies 3 participants last post by  Tokyo Torquer 
#1 ·
Here are some pics of the revised and newly detailed engine. Here's what I did and the learnings that came with it...

http://www.cardomain.com/ride/689541/2

-Changed engine block color from black to cast iron grey. Good thing I found out before I installed the engine because the cast grey paint is more like primer and it rusted in the garage due to humidity during a rain storm. I was so disgusted I walked away from the project for 2 weeks. I disassembled half the engine and repainted same color, but used a heavy clear coat this time. Doesn't look like the cool raw cast anymore as the clear darkened the grey a lot and made it very glossy, but it still looks good and wont rust this time.
-I added brass freeze plugs to replace the Dorman steel...the color contrast looks much better and more detailed. Removing rear-side freeze plugs can be a bi#tch compared to the rest.
-I polished the aluminun heads..looks good, but not worth the time. If you do it, only do the fronts, as the sides and rear cannot be seen with the engine in car and headers installed. Doing the whole head takes foorrreeevvvver.
-I learned that unless you are 100% sure it needs replacing..don't touch it! Since I had it all apart, I decided to change the main & rod bearings, even though they were still in good condition after just 800 miles. I changed to a full groove Speed Pro race bearing and then found I could not get enough crank end play. After 10 hours of grinding (thrust face of rear bearing) and fiddling and throwing tools, I could only get .002" of play. I went back to the Clevite bearing (H-series this time) and managed a minimum requires .004" of play. I wasted much time and money. Should have left original bearings alone. I blame the difficulty in getting enough end play on the @*&*%$ Eagle crank. I will never buy another item from them as I have had several machining issues with this crank.
-Installed Stef's pan..expensive, but a cool piece..hope it fits the frame rails good. I made a change since I beleive it was the chrome pan causing my rear leak dumping oil into my bellhousing.
-Super Comp headers were recoated after the Jet Hoat coating turned white when I blew a blower gasket and she started running lean. This time I use AirBorne Coatings. The finish is very different than the Jet Hot Coating. It is an aluminum-ceramic, but looks more like chrome compared to the Jet Hot coating. The finish is also much harder than the Jet Hot coating, impossible to scratch or mark unless you took a knife or sharp screw driver to it. The only negative I can see so far, is that they did not do a perfect job polishing the new finish between the header tubes.
-I went to stiffer valve springs and much titanium to address by 6000rpm valve float issue. Many people found it hard to beleive that I had a valve float issue with the mild roller cam and rev-kit, but I did and couldn't rev to peak RPM/ horsepower. When I felt it hit the wall about 6000-6200 rpm and let the rpms come back down, the engine would run rough and pop through the exhaust for a minute until the hydraulic lifters re-adjusted themselves. I now learned that many hydraulic rollers should aim for 140-145 pounds seat pressure no matter what the Cam manufacturer recommends. I set the valve lash at 1/4 aditional turn after taking up the pushrod play. I had recommendations from "experts" ranging from 1/16 to 1 full additional turn of pre-load on the rocker nut, with less preload improving rpm capability. I found 1/4 turn easier than 1/16 of a turn to adjust consistently on all rockers. I would never exceed 1/2 a turn, in spite of recommendations in the engine building guides. I thought some Titanium parts might help too, but they don't feel that much lighter than the steel ones..they are still more than half the weight, but many times the price!! ..especially the titanium valve locs. I over did it.
-I went to an 8mm blower drive and gold zinc-plated allen-head bolts to match the brass freeze plugs. Boy does aluminum really expand when hot. I would leave the blower belt loose with 1" play cold and it was like a guitar string when it got hot. I loosed the 1/2" pitch belt some more so I didn't shear off the end of my crank and the belt would jump teeth. The new 8mm drive set up will never jump teeth even if I leave the belt loose. The blower whine will also be different. 1/2" pitch belts can be louder, but only make the cool blower noise when engine is under a load above 2,000 rpm. An 8mm drive set up does not have quite as loud a whine, but makes it more frequently even without much of a load on the engine, such as reving at a stop. However, I had to replace everything to make the change. I thought I could just change the belt and pulleys, but the spacers and idler all had to be replaced as the 8mm competition belt is wider than a 1/2" pitch drive. Always something ..and never as simple as you think.
-I am running more boost than I had originally planned, so I switched to Cometic MLS gaskets..expensive at over $150 a pair.

I know how it all works out when I put the engine in. Hoping my valve float issues are solve and hoping the rear main seal doesn"t leak anymore with the new rear main seal and the different pan. I think the chrome pan was the culprit, but now a fearful thought has come to mind..what if the leak is caused by mis-machining of the eagle crankshaft diameter where the seal rides. I will freak if it still leaks. 550 ft pounds of torque and a amnual transmission aren't a good combo with engine oil dripping into the bellhousing. There was much mis-machining of sizes on this crank, including the pilot bearing hole..I had to have a custom bearing made as the hole in the crank end was too big.
 
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#2 ·
On polishing the AFR aluminum heads...they are generally very high quality heads with fantastic out-of-the box flow, except for the quality of the exterior casting itself. The biggest difficulty was the numerous big pits and holes in the casting surface. The pits really stood out once polished and required removing a lot of metal to get most of them out. Several were too big to eliminate. My Canfield heads had almost no flaws in the exterior of the casting.
 
#4 ·
Yes, I have had it to the track, however..

With the old NA 355 engine, auto trans and 3.9 gearing I was running high 12's at 106-108mph...then I added a whole bunch of power and took it to the track at the end of last year to see what it would do on street tires (BFG TA Radials) before I put it away for the year..big mistake.

Car weighed in at 3,818 lbs with me in it and a 3/4 tank of fuel.

We effective launch gearing is 4.33, so with this much low end torque I launched at idle in 2nd gear and still ended up smoking the tires past half track no matter how much I back peddled. I knew a solid launch would be futile, but just wanted to confirm trap speed to get a sense of how much hp I was making, but even that turned out to be futile. My best mph was 115 with a 3+ sec 60 foot (yes, I was trying to back peddle, but..) and 1/4 time of 14+ secs. No joke!! I just sit and spin the tires going no where. With street tires, I can smoke them even at highway speeds.

I later discovered on disassembly my new clutch was burning up and have purchased a stronger set up. Car should be capable of low 11`s or perhaps high 10`s at 123+ mph. I don`t have a roll bar, so my goal is to be able to do the legal limit of 11.5`s all day at 120+ mph with an easy 2000rpm launch. Rest of the car is legal for 10`s except for the roll bar which I definitely do not want in the car.

I have since purchased a set of new 10 X 26 MT ET Drag slicks to help with the sorely need traction, but won`t be able to try them out until I get this new engine back in the car.
 
#6 ·
effectively I have 4.5" back spacing.. 3.5" on the rims, but my moser rear end is narrowed an additional inch on each side. For a stock width rear end, I think a 5" backspace would be the best.

Those are Weld Draglites 15X10's.. they make 3.5, 4.5 and 5.5 backspacing, but no 5.0.

There is a lot more work than just re-locating the springs.. you would have to narrow the fuel tank and relocate the shocks... and you would only gain a tiny bit of room unless you mini-tub on top of that.
 
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