mopower

Here's a question for the TB IV ignition garus out there. I have an idle problem that's been driving me up a wall
My 540's will sit there and idle all day at 8/900 rpm when put in gear they want to stall. OK , so I set the idle to 7/800 rpm in gear , shift to neutral and I'm up to 14/1500 rpms.
I had it suggested to me this afternoon that when idling near 900 the advance may be starting and I'm not at my initial timing setting. So when I put it in gear and it drops some more I may be losing a couple of * of timing causing the engine to slow some more . I didn't have a change before work to try this theory but it sounds reasonable.
Was talking to Dean Nickerson and he said toss the 330 module for the V6 that should clear it up.
Carbs have been checked , rechecked , adjusted and readjusted and they are fine.

Gotta do some work now but will check back in an hour or so
Thanks

bobby daniels

It the CRANE boxes you need MSD they have super extreme unreal gosh darn wild terrible mean current to the plugs and the crane well ,, I let my 2 year old hold the plug wires to check for current he smiles when its firing ,,NAAA

the v6 box will help for sure but try locking it at 30* at idle and it will idle better and dock better ect ,,,30 to 32* is all the total you need ,, SMILE ITS CHEAP AND EASY

mopower

Phew , I knew that was coming
Problem is , I don't have Crane boxes. Just plain ole' ordinary vanilla Thunderbolt IV. Mainly because they keep on working.
Because of the idle speed of the engine , I'm getting into the advance curve of the TB and causing the idle to go high when shifting to neutral. When these engines were dynoed they used a locked out GM HEI set at 36* Also we couldn't "put them in gear" at an idle on the dyno.

HiPerf2000

iTrader: (2)

i may have a used pair of v-6 modules...i'll have to look for them.

i use one on my 575sc, and it works great to control the idle.

bobby daniels

yes its a common problem ,,just lock the timing and enjoy

mopower

Hi-perf...You got mail

jpclear

T-bolt IV is a good system. I had a similar problem with my 540. Some of it was a bit too much carb. with the 1050 Dominator. The V-6 module, which gives 14 deg. adv. on a V-6 will give you only around 8-10 deg. when used on a V-8. So, If you want, say 34 deg. final advance, start at about 24 deg. initial. That should boost things considerably at idle but make for hard start cranking when hot. I have found that Merc's 20 deg. HP module works best for me set at 14 deg. initial. I can look up that pt.# if you're interested. --- Jer

mopower

Jer,
I'd like to know where the 20*HP mod starts its advance curve. That seem to be my problem. When I set the idle to run ok in gear , when I go to neutral the rpms go up to the 1000 range and I start to get advance and the next thing you know its running 1500/1600 and sometimes 1700 rpms.
What would be nice is 20* advance starting at 1500 rpms full by 3000

jpclear

I'm sure I got that chart in the shop. Will look it up and post for you tomorrow. --- Jer

mopower

Thanx