So im building an l67 ISH motor. The bottom end is from a 2000 firebird. Flat top pistons which are 9.4:1 vs the 8.5s the dome stock l67s have. 2.8 pulley, intercooler. Heads are ported, larger stainless valves and milled .030. Zzperformance NIC camshaft with headers. Im porting the blower and using a Northstar throttle body that will be ported. Manual 5 speed izuzu trans
Here's the questions I have:
1: pushrod length. Just wonder if anyone knows off-hand with 1.65 rockers, .030 milled heads and .063 head gaskets what size is best? I assume shaving .030 and then adding .050 on the rockers id be .020 shorter which is within tolerances. But maybe im wrong here?
2: on the subject of head gaskets... this engine was bored .040 over. Does anyone know or have a link to a company that has .050 or .060 bore multilayer head gaskets and or can I use L32 gaskets from like an 08? [Im actually a gm world class master technician, so ill just get them through my parts department if I could]
3: on a stock 99-03 pcm. Can they run a flex fuel sensor? I asked my tuner and he said hes never dealt with the blue and clear style pcms.
------------------ Matt Pelissier
[This message has been edited by Mattrevenir (edited 11-30-2025).]
Vintage-Nut
NOV 30, 10:25 PM
Welcome to forum Matt and you posted your questions in 'The Mall' which is for selling and buying ...
You want to repost this in the Technical Discussion & Questions section.
BTW, I very like your garage / shop - WOW!
------------------ Original Owner of a Silver '88 GT Under 'Production Refurbishment' @ 136k Miles
Mattrevenir
NOV 30, 10:44 PM
Oh damn lol
And thank you! Ive been putting it together for the last 3 years with side work money. Its my man cave/side hustle shop
fieroguru
DEC 01, 08:07 PM
1: Just buy an adjustable pushrod and verify the needed length for your specific combo.
2: Most of the headgaskets have the fire ring a little larger than the bore. You rarely need custom head gaskets for a simple over bore.
3: I don't think it has the Flex Fuel tables, but you could run E85 100% of the time and tune it for that.
pmbrunelle
DEC 02, 08:36 AM
quote
Originally posted by fieroguru: 3: I don't think it has the Flex Fuel tables, but you could run E85 100% of the time and tune it for that.
"E85" can be anywhere from E50 to E85, so I'm not sure how well that would work out.
