So I have a carbureted 1998 LS1 thats in an 85 chevy pick up. A few months back i cracked the heads so I bought a pair of 241's of an 2005 GTO i rigged up the my old coils on the center bolt valve covers and every thing worked fine motor fired right up. I let the truck sit for a couple weeks then when i went to go start it up again and it wont start. I replace the crank sensor cam sensor good battery i got the coils for the center bolt valve covers. and i just had msd test my timing control module they said it checked out fine. So my question is would the coils form the gto not be compatible with my msd box for the 1998 ls1 since it has different coils?

 

I know this may not fix your problem but are you sure they are 241's and not 243's? 2005 GTO has an LS2 but 2004 has an LS1.

 

why didnt you use the same coils you had on before? I would start by checking the plugs first. My car sits outside for weeks at a time and sometimes I have trouble starting it. ...or try spraying some starter fluid and see if it gives it a bump. Keep us posted

 

do you have fire when turning it over?

 

i didnt use the old coils because they wont fit on center bolt valve covers. And yes i've done a dynamic test of the coils and plugs they all fire off. And lastly i have resorted to using starter fluid but with no luck
And the casting number on the head says 241 the guy i bought them from said they were off a gto but he could have been blowing smoke up my a$$

 

Are you throwing any codes? fuel pressure?

 

its got a carb with the edelbrock timing control module by msd. and i dont have the software to plug in to the msd box to check my self but when i sent my box in to msd they said everything checked out fine.