getrdunn

iTrader: (7)

I can only imagine what your thoughts were when it blew back up through the carb at 5,500. The last dyno session I had the exhaust tubing blew off one side at about 6,000. Scared the livin **** out of me. If your using the stock ignition from a 525SC then it should have a rev limiter built in however I thought they were set internally at 5,250. If you could only find another distributor to rule the back fire out would be helpful. I know a lot of guys using that ingnition flawlessly however if you plan to run above 5,250 then you'll have to see if you can send them out to be changed. The rev limiter wouldn't pop back through the carb though, it only drops cylinders. Did you take the distributor apart to check for play between the shaft and the housing? I would get it dialed in with the MSD and go find yourself a good MSD set up. Not sure if that's what your looking for as far as an answer goes but you could be fighting this for a while and still not have what you really want.

HaxbySpeed

They definitely like around 34/35 deg. Sounds like a great package, the little 177's do pretty good on a 454. I did this one a couple years ago with Edelbrock marine oval port heads, stock 525sc cam, and 8.5:1 comp, stock carb with 95's front and rear.

kreed

iTrader: (2)

Yea, very stressful! Lots of beer that day! Distrib shaft is fine. New pick up in distrib too. If there was a rev limit, it would be in module....right? Do all Thunderbolt modules have limiters in them??? Found a V6 module that Im going to try on the second engine on Wednesday....Or , can I use the thunderbolt distribs with Msd blue boxes instead of the modules???

kreed

iTrader: (2)

you got some great numbers! I was really surprised w/ my 580 HP! I want you engines numbers! Mine made at least 600 FT LBS through 4700 RPM. We have small jets in front at 87 and 96 in rear. Second engine going on on Wednesday...........

BenPerfected

Make sure the ground is good on your Merc ignition box. The only difference on the Merc boxes is the advance curve...no impact on a dyno testing. The Merc ignition system should work flawlessly to a least 6000 RPM.
Were the same plug wires used on both distributors?

getrdunn

iTrader: (7)

The MSD should be plug and play and also the Cranes. With either one of those you wouldn't need the module. I am not certain what TB systems have the rev limiters. My TB 1V's did not. I hate to give you any wrong info on this as I know your time spent is important you have everything ready to go for your next session. I would PM Griff in regards to your deal here. Did you confirm what you have. TB 1V or TB V. So your components you currently have are Dist, Module and Coil, correct? No ign. boxes of any kind. Just want to make sure you have all the correct components and your not missing something. I thought I remember a TB system I had years ago on a 525SC having an additional box. That was back in 1993. To many buds since then. PM Griff, I'm sure he'll answer your questions.

getrdunn

iTrader: (7)

I am going to put together some budget build SC's and wondered if you used the stock/original rec port intake or did you use an oval port? Unless otherwise this was not the Merc 525/177. Did a lot of back to back testing on this years ago with NA engines.

kreed

iTrader: (2)

plug wires were the same. Maybe my module is bad????

kreed

iTrader: (2)

Used stock stuff like u said, no extra box. Used rectangular port intake. I think these are original blowers that Hawk put on. They do not say Merc SC on the sides.

HaxbySpeed

The original intake was badly corroded at the Tstat housing which seems to be very common. I replaced it with an oval intake and the factory blower with stock pulleys.