CobraMarty

Get a bored 62mm TB. There are many sources. Around $100. Check the forums and Ebay. They use the stock spring/ The F+B also use the stock spring. I don't know of anyone that uses a heavier spring.

CobraMarty

You built a Torque Monster and not a HorsePower Queen.
Jeep Strokers and Jeeps with superchargers will put up impressive torque numbers and less impressive horsepower numbers. You have both.

Check out my DYNO page.
http://jeepm62superchargerkit.blogsp...g-page_15.html

CoffeeCommando

BBK. It felt like it was more suited to 300lb truckers. And I work out.

CoffeeCommando

I found a 62mm'er on Ebay. It's on the way. I'll pop that bad boy on after I get it back.

You guestimate another 1-2 PSI? So I guess that means I should up the fuel curves 5-10% in the tables as a starting point.

CoffeeCommando

Now that I think about it I bet the reduced airflow adds more parasitic drag on the belt line too.

concealer404

Why would increasing motor flow without doing anything to increase supercharger speed increase manifold pressure?

CobraMarty

Great, TY! The 62mm TB should add about 1 pound boost. Your fuel table should already have what you need for 1 more pound of boost.

IDK that about the BBK TB. For $299-$349 I never even considered it.

Any twin rotor SC needs as much restriction free on the inlet side as is physically possible, size wise and part availability wise. They can 'suck' air easier, more air, and more air in = more air out. The SC will work easier and make lower charge IATs and more boost. Next year I bet there will be a 70mm F+B TB under the Christmas tree.

Kind of like sucking thru a small diameter straw vs. a bigger diameter straw.

I also think that the real truth is that guys with strokers way overestimate the true power. 275hp maybe on an engine dyno, no accessories, large 4 barrel manifold and 4 barrel carb and good headers and no cat or muffler. Very few Stroker guys actually put them on a chassis dyno, I think they are afraid of the numbers. Strokers don't add much hp but they do add nice amount of low end torque.

CobraMarty

So you dyno'ed it, Are you driving it on the street yet? If so, how is it?

CoffeeCommando

So I just got a call. They checked the cylinder pressures and it's 65 PSI across the board. Why they're checking that now I don't know. That should have been identified before the Dyno so they owe me another one at the end. I think it made excellent WHP numbers considering 42% cylinder compression.

I'm going to call chad and tell him what we've done and get his recommendations, but I think my initial idea of ordering shorter push-rods is going to be the solution.

CoffeeCommando

I talked to Chad and he thought maybe the shorter pushrods are too short. So I called the place back and after talking to him about that and what they did cylinder to cylinder he said they got 110 PSI on the first cylinder with the stock pushrods with 5 .020 shims.

That was essentially a 9.540" pushrod vs. the stock 9.640". The ones in there now are 9.500", some with shims making them 9.480". So I told him to switch to the 9.560" rods I also ordered on piston one and shim from there to see if the compression goes back up. I might actually need a slightly longer pushrod from what I ordered.

I should have an answer within a few hours as to what that did.

CoffeeCommando

It appears the lifters are a major suspect. They've been noticing that the lash adjustment on the rockers have been adjusting after being set. I haven't made mention of it because it didn't seem like the issue. I figured the geometry was just off.

They adjusted the lash, then let it sit for 3-5 minutes. After that it was loose again, and they tightenend again. It happened again and there was no more room to tighten the rockers without really cranking on it with a breaker bar.

Suggestions? Has anyone ever experienced this jackassery? I want an easy solution but the only one I see is buying new lifters, specifically from a web site that specifies they're for 1998 model year engines and later. Which means pulling out the head, manifold, headers and supercharger.

I've only ever had completely failed (collapsed) lifters. Are the lifters for the older engines designed for less valve-spring resistance?

CobraMarty

This is so wierd. Just thinking out loud-
What springs are you using? close pressure? open pressure at .450" lift?
The hydraulic lifters do not have LASH, they have pre-load. IIRC about .030-.060" preload.
If the springs are too heavy at closing, they may be causing the lifters to 'bleed down', and then on compression test, it shows up 'low' due to low lift from the blead down lifter, but after starting the engine and there gets oil pressure to the lifters they 'pump up' and it runs, sounds well and makes good power. They lifters might be fine and the springs are too heavy/strong.
Maybe try and check a compression test quickly after running and turning off the engine before the lifters have a chance to bleed down.
Wierd problem.

CoffeeCommando

Stock 4.0 style springs through Golen. I specified it along with the use of a stock cam when I had it built.

I had them start the engine for the cylinder 1 test with the 9.560" rods. The results of leaking compression were still the same despite operating temperature.

I called Chad and asked him about it. He thinks the rods aren't the proper length. I have to agree. I ran the idea of worn out springs in the lifters from having rods that are too long across him and he didn't agree with that. He's never seen anything of the sort and he builds engines for a living.

I don't know if my shop got a hold of him or not. I was quite busy at work today. I'll follow up tomorrow when they open and see if he got a hold of him and found something out. 200 WHP on a low-H hi-TQ cam seems like 200 WHP might be about right... but I expected better since I designed every aspect of it to maximize full dynamic compression in conjunction with boost. This is clearly the reason it only got 3 PSI, but I want to see it at 4-5 PSI with maximum cylinder compression. I planned this build out expecting to see more impressive numbers, yet not over-the-top because I want it to last a long time and at the same time get better than 10 MPG's. I won't be a boy forever... and the zombie apocalypse is coming.

CoffeeCommando

Just sitting here thinking about the older cam style and you mentioning it walking.. and my transmission.

I wonder if the transmission problems affecting the thrust bearing, via pushing the cam shaft, are what was moving the cam around and if that's what caused the cam-synchronizer gear-wear-down.

Still waiting for the machinist to get back with chad about the measurements they got with the dial indicator while using the stock pushrods so they can get an estimate of where to move from there.

CoffeeCommando

Rods were too long for the new cam-lifter setup according to Chad. I ordered them from him yesterday. They'll be there Friday. That should be the final step.

Here's what I ended up needing with the Mopar cam/lifter setup:

Exhaust Rods: 9.640" (with 1.5 turns of pre-load)
Intake Rods: 9.600" (with 1.5 turns of pre-load)

Chad said that the lifter style is what would have made the differences in the setup. I understand that, but I don't see how that pertains to the differences in intake and exhaust lengths. Are the factory rods different lengths as well?

Kenny measured the ones that were in there from Golen and said they were 9.649" long. I assumed they were the stock 9.641" length when I made my first purchase of rods.

I didn't ask if everything else was in place. They tend to forget to do other peripheral things that need fixing whenever the main project on the vehicle comes to a standstill.