Hello,

I recently put a LT1 350 with iron heads & 10.5 to 1 CR into my Z28. In the near future I plan on doing a head and cam swap. I believe LT1's have roller cams and roller lifters.

My Goals are to:

1) Keep the car streetable and highway drivable
2) Make around 425hp and good torque #'s
3) Not have a rough or crazy idle
4) Have a nice powerband where I can utilize my 2400-2800 stall
5) Keep good vacuum to the power brake booster
6) Not have to use steeper gears than 3.73 (preferably 3.42)
7) Use pump gas
8) Use 1.6 rockers

So my questions to you guys are, what should I be looking for when selecting a cam and keeping all that in mind?

What determines how good heads are (what are the most important #'s beside price) and what should I be looking for when choosing a set plus keeping all my goals in mind?

If you guys have any suggestions on which would be a good head and cam package for me, feel free?

Furthermore, any opinions about my goals are welcome also.

Last question: If I was to build a 383 LT1 or 396 would your suggestions still apply?

Thanks in Advance,
Jay

 

I thought the factory LT1 heads were quite good. (oh, iron? not AL? This is like a caprice LT1?)
Maybe try porting those, I was under the impression they were good.
Or look for a 190CC aftermarket equivalent.

Then look at a cam in the 220/225 duration @ .050". Like a compxr264 or something. That'll keep your powerband fairly low to use that stall. I don't think that'll quite hit the HP you want though, you'd need more cam, and a bit more stall, like 3000RPM.

1.6 ROCKERS - not lifters. That won't be a big deal.

I'd seriously look at the stroker conversion, at least to a 383, if it's not hugely expensive. Make the power easier, keep the powerband lower, etc etc. Very good idea.

 

Sonix,

Yeah this is the iron-headed Impala SS motor.

Okay say if I were to get that cam (compxr264) and have some aluminum LT1 heads ported. How much HP do you think I would be around?

Also if I went with the 383 stroker LT1, more cam ( what type?) and 3000RPM stall would I be able to get the HP I want and still keep my driveability?


Thanks,
Jay

 

I just thought that I would mention that Summit has a head and cam package for an lt1 that makes 425 horse.It's pretty pricy but you should look at it.It will give you ideas on what cam and head specs you should be looking at.

 

got a link jocool?

I think that setup would bring you in the high 300's, AL LT1 heads and that cam, almost 400HP at the crank say.

If you went 383, you can go up to a 276hr or so, and the 3000RPM stall would give you the 425HP I think, along with keeping the powerband mild. I think the LT1 AL heads might still work for this. I remember hearing they flow well, but i'm not sure how well. I think the chamber size might need to be opened up with a 383 though, or else the CR would be too high.
-Jay

 

Try this.LT1 to LT4 conversion kit.I'm not sure how much power you would really make with that setup.However it should be a fun read for you and will give you something to base your build off of.








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