LayItLow.com Lowrider Forums banner
1 - 20 of 20 Posts

·
Registered
Joined
·
16,068 Posts
Discussion Starter · #1 ·
Anyone know the "best" spark plug for my buick 307 engine? How about the plug gap, (i think it should be .060, not sure though). I have a Haynes manual for buick 1974-1987 and it doesn't seem to give many specs at all for an 86'.

just want to make sure i get some plugs that'll last awhile and are the correct heat range.
 

·
Registered
Joined
·
15,195 Posts
ac delco. .035 should be good. im sure someone will come aroudn with a part number. do a search - its been covered before.
 

·
Registered
Joined
·
16,068 Posts
Discussion Starter · #3 ·
wow, .035 i would have thought more than that. I picked up a set of ac delco's already part # 41-630

Just seeing if there's something better out there before i put em in.
 

·
Registered
Joined
·
15,195 Posts
the first set i got was a set of nippon denso. fuckers fouled up, but kept on ticking. i played with a couple of different ac delco plugs before i found the right ones for my application :)
 

·
Registered
Joined
·
16,520 Posts
Originally posted by cashmoneyspeed@Sep 5 2005, 12:48 AM~3753779
wow, .035  i would have thought more than that.  I picked up a set of ac delco's already part # 41-630

Just seeing if there's something better out there before i put em in.

i got those same plugs in my cutty and it runs pretty good




WHAT EVER YOU DO


DONT BUY BOSH PLUGS OR PLATINUMS
 

·
59 imp 64 imp 77 mc
Joined
·
11,239 Posts
Go with a AC Delco plug, your part store will tell you the exact gap for your vehicle on these plugs. On my 87' cutlass with a 307 I gapped at .045
 

·
Registered
Joined
·
3,053 Posts
Really you can gap plugs more or less than spec, if you gapped it more you could probably get a little better mileage, the HEI should be strong enough... but .045 is whats in the book

and it has 'R45TS' for the plug unless the engine sticker says use another # then use that one
 

·
Registered
Joined
·
16,068 Posts
Discussion Starter · #14 ·
Thanks man. Just for reference, what page did you find that on?

Plugs that i got from autozone seem to be around .060" already. So basiacally they should be somewhere between .035 and .060, :uh:
 

·
Registered
Joined
·
3,053 Posts
Its in chapter one 'routine maintenance' page 1-4 its an older book though...

To answer your first question, AC-Delcos are the best plugs...

If this is a tune up youre doing and you already replaced the cap, coil & rotor you can gap them wider than stock without a problem because your ignition system will be strong. Up to you though, what I would do is make sure I have the right # plugs first, then do .055 assuming you already went through the ignition recently, if not, then .045 and call it a day

Gapping at less than spec. hurts gas mileage and plugs foul more often
 

·
Registered
Joined
·
16,068 Posts
Discussion Starter · #16 ·
Yeah i think i'll just put them to .055". I'm replacing cap and rotor, p;ugs, wires, and all other maintenance items at once. Not sure how long the coil has been in but i haven't had any problems from it yet.

I got the ac delco #41-630 plugs
 

·
Triple OG
Joined
·
11,047 Posts
I've got delco r45ts gapped at .035


they have alot of other ones though...r44ts r45t...ect

just heat ranges.

Try the r45ts and see how that works for your engine. If you have problems, switch heat ranges.
 
1 - 20 of 20 Posts
Top