Has anyone used the custom headers from oldsparts.com? They look nice, are compact but pricey at $699. I can’t find any reviews or opinions on them but I am intrigued. I have a 69 cutlass that is in the rebuild process

 

Try these people, they made them.
https://www.thorntonmusclecars.com/p...***-350-engine

 

I bought Thorton shorty small block headers in 2019 and paid $270 shipped. I thought that was pricey at the time.
If you are looking for max power buy full size headers otherwise outside of the current price, I'd recommend them. They will connect right into the factory exhaust system with no mods.
I used Pypes Stainless Steel Exhaust Downpipes DOF10S and ran them into a 2 1/2 inlet muffler.
You can also install the headers while the engine is on the engine stand and drop right into the car.

My only complaint about them was they use metric exhaust bolt studs. (for connecting down pipes to the headers)

 

It's starting to seem that Oldsparts is the new (old?) Mondildo. Anything they sell is available from somewhere else, probably cheaper.

 

Cheaper….but maybe not so in the long run.

https://www.sitejabber.com/reviews/oldsparts.com

 

This thread is a doozy.

From the beyond brutal reviews, to the fact that the item went up 280 % shipped, over the past 5 years.

And the final caveat, shorty headers do almost nothing for our engines. Any measurable gains will only materialize on the extreme end of dyno tuning, or track testing. Essentially shorties are fake headers, created under the guise of not enough room. For those that don't really want headers but think they are still getting header power by compromising. Because the item shares part of the name.

P.S. TiscOlds69 this is not directed at you. Just a general observation.

 

They are "header flavored" manifolds and give you as much improvement as putting 442 badges on a Cutlass. These are not even short headers as the tube lengths are not uniform. A lot of cars come from the factory now with a short header under a shroud as opposed to a log manifold. It gives just a little help.

 

Curious as to what your evidence of "shorty headers do almost nothing for our engines" and "They are "header flavored" manifolds and give you as much improvement as putting 442 badges on a Cutlass."?
Are you saying the lack of proof of a performance gain means there is no performance gain?

While people are entitled to their opinions, problems arise when opinions are presented as facts.

 

I thought cutlassefi had posted dyno results for shorties vs full length headers.


Edit: found]d the post in a quick search:

https://classicoldsmobile.com/forums...eaders-177221/

 

It's even worse than that. There is performance loss on occasion.

Here are facts.







https://www.motortrend.com/how-to/hp...-vs-manifolds/

 

I wish the stock Oldsmobile small block exhaust manifolds were designed the same way the Pontiac log manifolds were.
The results of that test are more nuanced then you stated above. I like how you picked the data that backed up your case but left off the other charts in the same article.

Once again if your looking for HP obviously go with the long tubes. I haven't seen a back to back dyno test that compares the Thortons to the stock manifolds so I agree the jury is still out on what benefit or detriment they provide. But to say they do nothing based on an opinion isn't right.

 

Key quotes from the aforementioned article.


"Jim Wical at Hedman also warned that the shorties don't do much on a stock engine. I assured him that our 389 was not stock."


"I was told that the shorty hedders didn't do much on stock engines but less than logs was surprising. In another test performed by Terry McGean at Car Craft the shorties showed no horsepower gain over logs on a stock 455 but showed some torque increase (after mods the shorties performed well)."


With regards to the 455.

"Shorty headers do have a place in the line-up. In our second test with the mandrel-bent pipes they posted 1 hp better than the RARE manifolds and 3 better than the Performance Years pieces. They are much lighter than the manifolds and will provide some sparkle under the hood with HTC coating. On how they fit in an engine compartment we cannot comment since we did not install them in a Pontiac chassis."

I read that last paragraph as, they are a "feel good item".

https://www.motortrend.com/how-to/hp...-vs-manifolds/

 

V8AL

I get it trust me. A part of me wants Thorntons on the 69. I've had full length on a 67 and they were a pain in the *** on the street. The thought that I could have a little bit of that perceived oomph minus the headaches is very tempting. But I know its a fantasy unless my car is set up lights out. My ride is leaving 30 HP on the table as is, 4 more HP if that, and a little more sound is not worth it ... to me ...

For those that are interested and haven't pulled the trigger. If it's a must have, knock yourself out, go for it ! And I am not being sarcastic. They look cool and at the end of the day you have "headers". If you are building an engine and the exhaust manifolds are missing/need replacing, makes even more sense.

 

im not sure you realize it or not..that’s a Pontiac 😂😂😂

so those facts, are meaningless…not only because they are cast iron, not the stainless individual runner pipe style shorties this is about.

you are a clueless..im being nice

 

this guy is full of it…Im being nice

 

Interestingly, nobody has mentioned if the Oldsparts.com headers fit without modification with a BFH. I @$$ume they'd fit a Cutlass since they are shorties. Probably not a Cutlass S though.
​​​​​​

 

Usually people make comments when they don't fit. I didn't have to do any massaging when installing the Thorton 350 headers in a 72 Cutlass w/AC.

 

Thanks for the good advice. I was lured in by shiny things and the promise of no modifications. I hang my head in shame for my weakness lol

 

the truth is that price is way up there. I’ve seen them used for less than half that..which is worth it. the truth about the performance advantage is they are much much better than the factory small block exhaust manifolds… especially when used with 2.5” down pipes. they are also better than the Thornton cast iron small block split flow manifolds which are the same price…those need a lot of grinding to be made usable because they a poor Chinese castings

some guys just hate headers hanging down under the car, especially if it’s at stock ride height.

don’t get caught up in the internet hate for these things..think clearly, look at them as an in between solution to full length headers and stock iron olds manifolds

that test done on the Pontiac engine does NOT apply to the small block Olds..not even close

if you need more explanation, just ask. Here’s a test with them in a small block compared to Thornton cast ones and long tubes..they did very good