Im curois about a hemi

butterbagz

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So a guy gave me a really good deal on some expensive parts since I'm a kid and he wants to help me out for 150 he gave a hemi rod pvl flywheel 28/25mm hemi racing head a header a new crank stainless valves a 310 cam air filter adapter and some valve springs I'm curois what a build like that would hit rpm and horsepower wise?
 

Rat

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Takes more than a box of parts to make an ok engine great.
What a Hemi lacks in compression, it makes up for in flow volume and velocity through the head.

The only good thing about not being able to really go nuts with head milling is that unless you have the chamber welded, ground, polished, and redecked you'll never make enough compression to use higher than 87 pump gas or 90 non ethanol gas
 

butterbagz

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Takes more than a box of parts to make an ok engine great.
What a Hemi lacks in compression, it makes up for in flow volume and velocity through the head.

The only good thing about not being able to really go nuts with head milling is that unless you have the chamber welded, ground, polished, and redecked you'll never make enough compression to use higher than 87 pump gas or 90 non ethanol gas
That stuff had already been done to it
 

Thepartsguy

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Takes more than a box of parts to make an ok engine great.
What a Hemi lacks in compression, it makes up for in flow volume and velocity through the head.

The only good thing about not being able to really go nuts with head milling is that unless you have the chamber welded, ground, polished, and redecked you'll never make enough compression to use higher than 87 pump gas or 90 non ethanol gas
You don’t understand how right you are! I saw a stage 1 kit today in the forums and it was a good post.

He wanted to buy a stage one kit and a Nibbi carb..

I was thinking that 90% of the stage one kit wouldn’t be used if he switch to the nibbi the only thing he would use from the kit is the header and air filter 2 pieces out of a 15+ piece kit.

It’s like zipties and clamps a header wrap it’s all unusable and the nibbi alone would make more power about the whole stage 1 kit. Not sure why people buy it..
 

butterbagz

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Takes more than a box of parts to make an ok engine great.
What a Hemi lacks in compression, it makes up for in flow volume and velocity through the head.

The only good thing about not being able to really go nuts with head milling is that unless you have the chamber welded, ground, polished, and redecked you'll never make enough compression to use higher than 87 pump gas or 90 non ethanol gas
I'm going to run the hemi if I do like it then I'll keep it like this , but if not I'm going to try to get lucky finding a 32/28 non hemi cheap used
 

butterbagz

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Takes more than a box of parts to make an ok engine great.
What a Hemi lacks in compression, it makes up for in flow volume and velocity through the head.

The only good thing about not being able to really go nuts with head milling is that unless you have the chamber welded, ground, polished, and redecked you'll never make enough compression to use higher than 87 pump gas or 90 non ethanol gas
Yeah that's why I really didn't want a hemi but this guy is really experienced with hemi engines and uses hemis, hopefully I find a non hemi head but this is a good start right parts for decent price and I'm going to build but he's clearencing the cam for me and other things
 

Rat

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Yeah that's why I really didn't want a hemi but this guy is really experienced with hemi engines and uses hemis, hopefully I find a non hemi head but this is a good start right parts for decent price and I'm going to build but he's clearencing the cam for me and other things
A Wedge with large ports (30/27) will flow about as well as a stock Hemi (27/25 or 27/24) So if you're going for maximum then a milled large port Wedge might be the better choice.

I've head swapped both ways and until you get really wild the differences in performance are negligible
 

Rat

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You don’t understand how right you are! I saw a stage 1 kit today in the forums and it was a good post.

He wanted to buy a stage one kit and a Nibbi carb..

I was thinking that 90% of the stage one kit wouldn’t be used if he switch to the nibbi the only thing he would use from the kit is the header and air filter 2 pieces out of a 15+ piece kit.

It’s like zipties and clamps a header wrap it’s all unusable and the nibbi alone would make more power about the whole stage 1 kit. Not sure why people buy it..
I never bother with stage kits... I'd rather pay more and get exactly what I want then get a box of bullsh★t. Stage kits are for lazy builders and know nothing newbs.

I don't do Nibbi carbs, I do Keihin (COPY) Koso PWK24 on 196,208, and 212 engines... I'm working on a Hemi 301 that is getting a Genuine PWK28.
 
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butterbagz

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A Wedge with large ports (30/27) will flow about as well as a stock Hemi (27/25 or 27/24) So if you're going for maximum then a milled large port Wedge might be the better choice.

I've head swapped both ways and until you get really wild the differences in performance are negligible
Is there wedge heads for predator 212?
 

Rat

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There are some ugly PWK knockoffs out there.
Ya gotta be sure ya be getting the real deal.
I know. Keihin (OG) is Now parented by Sudco-Japan and the "Sudco" is often the tell... but the embossed name label never is.

Sudco/Keihin has never made the PWK series under 28mm so anything claiming otherwise is a scam or uninformed seller.

In my experience with copies and clones, OKO is NOT OK unless you modify it right of the bat due to an inadequate fueling problem both into the bowl at the needle valve and into the main jet pick up (over shrouded).

I wont touch a Nibbi, my preferred is a Koso simply for being so dead on of a PWK28-PJ copy in form and function just smaller by enough to run perfectly.

Genuine PWK 36 BELOW
20240522_200911.jpg1000002158.jpg
 

panchothedog

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So in your first post you described the head as a racing hemi head. I say run it.
It might be Killer. Many of the modified heads are the non hemi. But if it's been done correctly, and with the higher tension valve springs, it could perform very well. You list all the parts you have. Do you have the engine?
 
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