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L67 build questions

J

Jonathan0498

New member
Hello, I have a completely stock L67. In my Fiero with a 5 speed, and I was walking the junk yard, the other day. When I found a gold mine. It look like some one was building a l67 and never got finished because It was not all together, but it did have brand new CNC zzp cylinder heads, xp cam, push rods, double roller timing chain and Billet fuel rail. So I grabbed it all. But now I'm wondering, If I should go with a bigger cam or modified rockers. Before I put it in.
Ok my questions Are,

  • would it be worth it to get a bigger cam?
  • would it be better to buy 1.9 rockers
I know that 1.9 would be a lot of lift like .617/.636 but the the cylinder heads are milled for .600 and modified retainers with valve seals that give, An extra .05. That gives a total of .650. which give a .0135 of Clarence. Is that enough Clarence? The heads have #136 valve springs.
 


cam is best, xp is as big as your going with out head work really.

rockers help, but they just mimic the stock cams profile.

and you run stock rockers on a aftermarket cam, or 1.6 roller rockers if you like rollers. not needed tho.
 
you could add rockers to the XP cam, just need to take measurements and not exceed the limits. you don't have to add 1.9 rockers, you could do 1.7 or 1.8 and maybe not be over the limit.
 
jesseC651 said:
And where is this junk yard?
Click to expand...
LKQ Pick Your Part Savannah. But I got all the parts sorry

Scottydoggs said:
cam is best, xp is as big as your going with out head work really.

rockers help, but they just mimic the stock cams profile.

and you run stock rockers on a aftermarket cam, or 1.6 roller rockers if you like rollers. not needed tho.
Click to expand...
The heads I got are ZZP CNC and a xp. I was just thinking with these heads, maybe go with a bigger cam
 
SgtMarshal said:
you could add rockers to the XP cam, just need to take measurements and not exceed the limits. you don't have to add 1.9 rockers, you could do 1.7 or 1.8 and maybe not be over the limit.
Click to expand...
Intense only sells roller rockers now and ZZP only have 1.65 and 1.9 now :th_nervous:
 


i got yt 1.95's. they killed off 5º kr when i was still stock and untuned. they do work.

id still run the cam if its not all torn up. xp cam, go back get the headers if you failed to take them, run them heads and a 3.2 pulley and it will be hard to stop grinning i bet. did you say it had head studs? if so take them too. cause they are way better then stock tty bolts and are re usable.
 
I think you are referring to the study zzp did to show the effectiveness of their "ER Rockers" for NA 3800's, which as it turns out is not applicable in supercharged applications. Plenty of people have made good power with roller rockers. you could just keep it simple and use what you have, but add an intercooler instead of a bigger cam and/or rockers.
 
My plans for the build are.
  • Gen v supercharger
  • 2.x-3.2 pulley
  • phenolic intercooler
  • CNC heads with 136# that is what's in them
  • 60 #injector
  • Double roller timing chain
  • stock l62 lower end
  • xp or bigger cam ?
hoping 350whp through the manual
 


be closer to 300-320. but all the same that cars gonna fly. its super light. think another guy here ran a 11 or a 12 with a cam'ed 3800 Fiero. no ic yet for him, and his is a automatic HD with a gear change.
 
You might knock off 350~ or so without the slushbox killing it and ethanol.

You WILL need a 2.6" or so to do it with just a little XP.

Do headwork and get a big cam. I'd also venture to tell you to find an L36, not a 26. Seems to have a better track record with rotating assembly strength.
 
1.9's are nowhere near the lift you noted. Stock Cam profile is. 278 or. 530 lift with 1.9's. And for power, the Cam is the best way to go. As Scotty mentioned, high ratio rockers will only pronounce the Cam profile, provide sliglty better ram rates and more air in/out. But power will come from the duration and lobe profile, etc. You can go Cam and rockers if done right, I'm running Overkill BBC Cam and 1.8's right now and absolutely love it!

Just take some time to do the research, these engines have no unicorns and the maps are there for what you may want to build, power, street, track, SC, Turbo, etc. It's all there, no mystery!
 
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