porting heads...

[ericjon262]

ok, I'm bringing this back from the dead. I've been working on my Fiero, and I've slowly been gathering parts. I've got a ported set of intakes, a gt 35 turbo, and a recently acquired a bigger camshaft too(224/214 @.050 537/530 lift w/1.5 rockers) . how much do you think having the heads ported would be worth HP/torque wise? if I do it, I'd be having someone who knows do it, not doing it myself.

Edit:

I'm planning to run about 16-20 pounds of boost all out.

[3400-95-Modified]

It was a 1280 intake and 1331 exhaust If I remember the cam grind numbers correctly.

Well I'll see what she does at the strip this year and make a decision from there on what I'm going to do... Right now my biggest issue was traction over the power so unless I plan on ditching the Nitrous I don't think I really need to change much. Later on I may go for more n/a power and back off on the Nitrous shot.

[mfuller]

As I recall you used what was at the time a NA stage 3 intake lobe with a NA stage 4 exhaust lobe.

[SappySE107]

That sounds more like it. I do recall it not being the right LSA, and I know the lobes were from different cams. I never sold another one like that grind. We have more aggressive lobes available now, that have more lift area below max lift.

[3400-95-Modified]

No way your cam is stage 3 boost. I thought it was done for nitrous, using a lobe off one cam and a lobe off another.

It was a lobe from one and a lobe from another, but I thought I remember it getting sold as a stage 3 boost a while back. I could be wrong. Its also 112 LCA and you originally wanted 114 but the grind was done wrong. You did a check and it was only worth about 2-4hp though so I didn't mind.

Maybe its the exhaust lobe is from a stage 3 boost cam and the intake was from the stage 3 N/A cam... I don't remember since it's been a while since you changed to the Comp lobes.

[SappySE107]

No way your cam is stage 3 boost. I thought it was done for nitrous, using a lobe off one cam and a lobe off another.

[robert 1980]

I love my 3500 heads i just wish i had more cam=)

[3400-95-Modified]

When I had my cam profiled a while ago I was given a stage 3 boost cam IIRC... so that's another one where I wonder if you've learned more since you did my cam profile or if this cam is still a good option to be running... Either way I do agree that I am not entering in the realm of forced induction since I have no positive pressure in my intake so flow is still very important to me. No argument there.

I guess I should revisit my cam profile and head porting choice this winter.

[ericjon262]

I looked at the heads today and they have damage. Both of them.

I'll keep looking for a set. I know a good set of heads and intakes would make HUGE power on my 3400 cause it has a huge, lumpy dirty cam. 280 / 288 .57X lift. I have no clue what the redline is cause the needle is way past the 6500 tach and it's still making power, noticeable loss under 4000 though, I have to rev it to 5500 to not bog launch on the street for a good launch.

Edit, this in on my Fiero, obviously. Camaro doesn't have traction on the streeet till roughly 90 - 100 MPH.

fiero! what fiero!? got a thread to show us?

[Mars]

Well then send us the heads you mentioned and put them on the Fiero motor. We know how much you like dyno time, and you know how much pride we take in our work - let's do it up

I looked at the heads today and they have damage. Both of them.

I'll keep looking for a set. I know a good set of heads and intakes would make HUGE power on my 3400 cause it has a huge, lumpy dirty cam. 280 / 288 .57X lift. I have no clue what the redline is cause the needle is way past the 6500 tach and it's still making power, noticeable loss under 4000 though, I have to rev it to 5500 to not bog launch on the street for a good launch.

Edit, this in on my Fiero, obviously. Camaro doesn't have traction on the streeet till roughly 90 - 100 MPH.

[ForcedFirebird]

I knew what you meant, but in the case of nos, I don't think all out heads are a good idea because it's more of an on-off type system unlike forced induction.

As Ben said, treat NOS like N/A, I was just implying the gains when spraying would be exponential, just like the adding of n02 increases the N/A power.

[ericjon262]

I knew what you meant, but in the case of nos, I don't think all out heads are a good idea because it's more of an on-off type system unlike forced induction.

[ForcedFirebird]

I agree w/ ben when it comes to nitrous as a power adder, build the engine like N/a, as far as the heads go, now cam on the other hand I've heard makes a bigger deal with nitrous.

When I mentioned power adder, I was referring to the fact that the head flow will exponentially increase power. The power will increase much more than an N/A engine when it starts to get more efficient - if that makes sense lol.

[ericjon262]

One I'm not N/A, I'm Nitrous... I also don't understand how 3400 heads will outflow 3500 heads at the same stage. Seems kinda odd but I guess that just means you can't duplicate what can do on the 3400 heads on the 3500 ones due to the casting changes which is understandable.... But essentially what you would be telling me is I'd be better off with 3400 heads and LIM over the 3500 stuff?

And I got $800 by going to the 3500 heads adding the port work, adding valve job (since you strongly suggest getting that) and also added Milling since its wiser to have you do that then bring them somewhere else after I get them back, that comes to $729 or $789 depending on the milling cut you get. SO for my investment I'm looking at around $800 plus shipping both ways to get this done. I need to know what these "flow numbers" are going to give me in the end to justify the cost. If its only 5hp total I don't know if it's worth it. I'd rather just clean up the casting and polish the exhaust ports myself then and keep using the 3500 stuff.

I agree w/ ben when it comes to nitrous as a power adder, build the engine like N/a, as far as the heads go, now cam on the other hand I've heard makes a bigger deal with nitrous.

[SappySE107]

After looking through my numbers, I have come to a conclusion. I tried entirely way too hard to test everything possible. I need to do this again, but not with every detail. For example, stock heads, stage 2 lower, stock upper, 52mm TB. stock heads, stage 2 stock upper, 56mm tb. stock heads, stage 2 manifolds, 65mm TB. Stage 2 heads heads, stage 2 manifolds, 52mm TB. Etc. I was, and still am far more interested in the complete engine setup being used on the flowbench. I have 3400 vs 3500 exhaust manifold tests even. All of this is awesome for dynomation, to simulate HP results and cam specs, but I didn't get everything done. It certainly helped me understand what the best potential setup was though.

I don't have numbers for stage 1 or 3, so I am going to wait until the bench is done and get everything to post at the same time. I had S2 and 3 for the 3100/3400 heads already and S1 are very much not labeled within all the tests that have been done. Sorry if that means you aren't going to consider our port work because of this.

An otherwise stock G6 with stock computer with drive by wire gained 10 whp with our 3500 heads and manifolds. I would imagine something tuned would do better, and something with more mods would do even more.