head porting

[discostu]

Dynojets almost always read higher numbers then Mustang dynos...
Dynojets are "unloaded"... Very little load against the engine.
Mustangs put a load on your engine, and because of this, they show lower numbers. But they are also considered to be more realistic with respect to actual conditions.

[SappySE107]

Right, which is why you can't compare numbers. Hell, you can't really compare between different shops and be 100%. Too many things you can do with a dyno to get different numbers. Thats why you need before and after on the same setup to have any real idea of power gains.

130 hp 3.1? What did that come in?

[Arns85GT]

Maybe I am out on the 130 hp. It was a 1990 Cavalier. Was it actually 140?

Anyway, it went real good while I had it, but it wouldn't beat the Fiero.

Arn

[SappySE107]

140 hp. What does the fiero weigh? I figured both being a manual, the cavalier would be a good race.

[Guest]

Arn with your carb setup you only wound it out to 5200 rpm. It started falling off on power at 5k rpm. So for you to say it pulls to 6k is wrong. It pulls to 5k rpm.

So you went toa 3.1, did a carb and ported heads, a fresh engine and you picked up 25 whp. Most of that is probably just from the displacement increase and nothing else. Like I said, weak. I saw pics of your portjob. I gotta say they didnt' look all that impressive. Subpar I think is the word I want to use.

My 2.8 did 115 with stock heads stock everything through an auto. I dont' know if I have the graphs anymore as it was on my old 85 GT but I dont' know what the curve looked like. your 107 whp dyno run was on a dynojet, so was my 115 hp run.

If you say it pulls good to 6k rpm then when on the dyno wind it out to 6k rpm so we can see just how good it really is.

[RedBird]

liek was just said, you were on different dyno's, if they were set slightly different that could do the 8-10 hp difference between the two of you.

Also, there is no WAY that going from a 2.8 to a 3.1 is gonna give you 25hp. stock mpfi 2.8 is rated 130 and the 3.1 140. the head porting surely helped.

[SappySE107]

I agree, 2.8 to 3.1 is not 25 hp. Its rated 5 hp but id imagine the low end would be better on a 3.1 as well, which isn't something you compare when you just talk peak numbers.

So this thread is about head porting. Shaun seems to know everything so lets hear it shaun. Whats not subpar.

[bszopi]

Beretta's were rated for 160hp in 94, and then 155hp in 95 and 96. GM does wierd things sometimes.

[Guest]

arn didn't you say your motor was a 3.1? Even so the heads between are the same.

By the way for everyone here. tHe fiero was rated at 140 hp. Not 130 like the aluminum head or camaro 2.8's

How much do you think a fresh stock 2.8 puts down in a Fiero? aobut 115 hp or so. I have seen countless dynos around 115. So all that work got you 15 hp over a fresh motor. Since yours is fresh you have to cmpare against a fresh motor. Like I said. weak. But if you are happy with your mid 15 qtr mile times so be it. Just don't act like a hardass next to a stock LS intregra. You will probably lose

[SappySE107]

I want to see these countless dynos around 115 for a stock 140 hp fiero engine.

[SappySE107]

12-15% from an auto? Now where is this coming from? Is the fiero trans (3t40) that much better than the beretta (3t40). None of this makes a damn bit of sense to me.

Im also lost on what was done to go from supposedly 115 to a known 132 hp.

[Arns85GT]

Thanks. And much appreciated.

Arn

[Guest]

Where did my post go?

[SappySE107]

moved to off topic, called fiero crap.

[fivepointhustla]

Just don't act like a hardass next to a stock LS intregra. You will probably lose

I got a laugh out of this because I used to lose to modded VTEC Integras when I was stock cause of that $hitty intake, but that was only on the street. In the 1/8 I win.