Paul reached a goal, the old guy didn't !!

jeep_406 · Posted: Thu May 24, 2012 1:57 pm Post subject:

Maybe New England Dragway can't handle 2 SMOKEmUP members at the same time Very Happy

jeep_406 · Posted: Fri Jun 08, 2012 10:40 pm Post subject:

I finally did a compression check and leakdown test on my 408. All cylinders had a leakdown of 5-6%. Compression on 6 cylinders was 195. The other two were at 190. Next I'm going to check the valve spring pressures. We had a friend that picked up a bunch of MPH years ago because his springs had gone away. The 408 can still pull to 7000RPM. We'll see. I remember that Adam had suggested we look there.

Driving

clay · Posted: Sat Jun 09, 2012 1:05 am Post subject:

So far so good! When I ran a 200R4, the forward clutch gave up and it failed in a way it was almost impossible to detect. Mine did as you describe - just slow down for no explainable reason. Followed your path almost exactly until I finally gave up and looked at the transmission and all I can figure is the forward clutch was just sort of "creeping" instead of outright slipping because I couldn't feel it. I say this because you are right where I had problems - high 10's. When I called Transgo and told him what I had found his first question is are you almost in the 10's. I said I run low low 7's - high 6's in the 1/8th so yeah around there. He said that's when most people call us and there's not a lot you can do without spending a LOT of money. Hope this isn't your problem but if you exhaust everything else something to look at. Clay

jeep_406 · Posted: Wed Jun 13, 2012 9:40 pm Post subject:

Well, the Valve Springs checked out fine. I'm using Patriot Gold dual valve springs with titanium retainers (PN # PAT-8401) I measured 135 @ 1.800 and 375 @ 1.150 which put them right on the money per their site.

Clay, the tranny was just done with billet stuff. Supposed to be good for 800 horsepower. I don't know who makes the converter but I am able to footbrake it to about 3200 RPM.

The only thing evident is that there is a noticeable difference in exhaust sound. It was considerably louder last season. I'm figuring that has something to do with the loss of power.

We're going to look into the electrical system. I've noticed a pitch change in the fuel pump when I kick on the dual electric fans. I also have the ignition system and the fuel pump on the same circuit.

Driving

clay · Posted: Wed Jun 13, 2012 10:34 pm Post subject:

Glad to hear that on the transmission (and spings too). When I was trying the 200R4 it didn't have quite the aftermarket support it does now and I was using all stock parts - about the best factory parts but still factory stuff none the less. I don't know what type of mufflers you have but how about a baffle coming loose and partially blocking exhaust flow. Maybe a wad of packing came loose and has something partially blocked. Long shots but trying to think along the lines of you saying it's quieter. Clay

jeep_406 · Posted: Wed Jun 13, 2012 11:22 pm Post subject:

I run a 3 inch system from the headers to where they exit after the rear tires. The mufflers are Hooker and they are straight through.