I'm looking for some headers.

I was comfortable getting the Hooker 2055's and was gonna order from Advance with 20% coupon code. However, they have been totally out of stock for over a week now.
By the time I would get the a.i.r. pipes welded shut, pay to ship and have them jet coated, I'm starting to add up time and money.

So now I'm thinking about Dyno Don's. I've done some searching and most everyone who's bought them are using 350's or bigger.
Should the 1 3/4 primaries on my LB9 concern me? I don't wanna defeat the purpose of doing headers by going too big and losing torque or something.

Would Hooker 2460's get me better gains across the board?

I'm getting the engine rebuilt w/ported heads & new cam.

BTW: I know it's just a 305

 

You will gain over all better power with Dyno Dons Headers. Don't believe that crap that they are too big for a 305.

 

You will be just fine with 1 3/4 headers on a 305. Most people didnt know that SLPs 1 5/8s and 1 3/4 headers use the same size tubing. I didn't for a long time either until I measured my 2 off the car sets..

 

I have Dyno Dons 1.75" primary headers on my '91 LB9. I was amazed at how much power it picked up across the RPM band. No noticable loss of low end torque and quite and increase around 2200rpm-up. For comparison I had Edelbrock TES headers on my '85 LB9. And those didn't feel like they had nearly as much improvement.

 

Have you been to the track after you install the headers?

 

So ALL SLP headers are 1 3/4" or are they 1 5/8 " ?

-- Joe

 

They have both.

 

I realize that they have both advertised. His statement was they were both the same size..

-- Joe

 

I have not yet.

 

I believe he meant the y-pies are all the same.

 

Interesting about SLP.. Also interested in your comparison to the Edelbrock TES headers, which I have now and was considering painting them and wrapping them.. Perhaps it would be wise to just invest in a set of DYNO don's ceramic coated one instead? Does he route the y-pipe through the stock location?

 

Nope, the tubing for BOTH header designs are the same size.. Both are 1.622OD as measured on a straight unclamped area of the header primary piping.
I have a few sets of both. Even the early and late sets, all the same size tubing for the headers..
Sooooooo the design was the (diff, if any) in power between the two..
The Y pipes are around 2 1/4"(edited pipe size due 2 my fat fingers) outside dia and are not mut much bigger than the factory stuff. ( I only have dual cat stuff so I'm not sure about the single cat stuff.)

 

They route the same for single and dual cats

 

THey didnt accidently send you 2 of the same headers? They couldnt possibly be selling 1.622" headers as 1.75"....that makes no sense. Their 4th gen stuff seems to be correct from what i read.

Anyone else verify this?

1 3/4 is big for a 305 if a long tube but I guess the shorties doesnt effect it as much. 1 3/4 primary is good to 600+ hp depending on the combination.

 

Nope, I just went out and measured BOTH designs that I have. The 1 5/8 tri-Ys and the 1 3/4ones that Dyno Don based his off of. Both of these sets are early sets built in 1991-2. I ordered one set and the other is documented being installed on one of my cars in 92 when new.

The Tri-Ys do merge from 4 into 2 then the 2 into 1.. maybe they are measuring the the 2 pipe area on the tri-Ys.(just measured that pipe at 1.669 but it was a bad spot and it could be a out of round clamped for bending section)
The 91-2 Hawks came with the tri-Ys...

I just measured my 92 Tri Y dual cat Ypipe, its 2.25" OD for each pipe and advertised as 2 1/2".

SLP was very,very generous in their measuring..

 

Dyno Don base his headers from the SLP 1 3/4 and made Improvements plus easier to install and get to the spark plug better.

These headers will work just fine for a 305.

 

Looking to get a set to go with the upcoming CTW Motorsports' project Camaro...

 

To jump on the 305 testimonial bandwagon, I have Don's on mine as well, and notice a pickup around 2500 RPM as well.

 

Do Dyno Don's headers have better clearance for aftermarket flaming river steering shafts? SLP's would rub slightly on those IIRC.

 

Yes! Better clearence than SLP even the same for spark plugs.

 

Doing spark plugs with Dyno Don's is easier than any other header, even the stock manifolds.

 

I put a set of Don's headers on a buddies 87 IROC with 91 motor and 87 TPI accessories. Had to move the coolant pipe on pass side to clear the passenger header.

On the drivers side the header hit the crossmember. The correct factory motor mounts clamshells were installed in their proper location & previously installed Edelbrock TPI TES header system had no clearence issues. Had to install POLY motor and tranny mounts to lift the motor a little higher so the DD headers would no longer make contact with the crossmember on the drivers side.

Check headers closely for clearance before ever touching the Y-Pipe !!!!!

The 87 IROC also had a factory Oil cooler,..... that was never an issue when installing DD headers.

No proof of performace gains, this post is only intended to share my experience with those members that plan to install DD headers on a TPI Thirdgen.

 

I had the SLP Tri-Y's when I was running my 305 and loved them! I stepped up from the Edlebrock TES along with some other goodies so I don't know how much of a gain they were but the overall combo matched good! My lil engine that could produced 240rwhp and 309rwtq and the car ran 13.6's at 101mph. Never could find a sweet spot for launching though but I never had drag radials at that time either. IMO a 1-3/4" is a lil big for the initial powerband of a 305. It's the initial torque/power your relying on for launching. Gear for a stick and converter for auto is a must though! Although there really isn't much choice in headers anymore so might have to go that route. And the 1-3/4" will always help in the long run if you decide to do more ci's! Good luck!

 

I just noticed the note on your engine rebuild.... any particular reason you don't find you a 1pc rear main 350 truck block and rebuild that? Costs would be almost identical, then you would definitely benefit from DD's headers. Just my opion.

 

Not sure who you're referring to, but if it's me then I don't know it was rebuilt before I bought the car. I would have gone 383 if I could do it over (it's coming soon actually).

 

The original poster noted about a rebuild.

 

I went with the Hookers, I ordered them from summit. I feel as though they flow plenty for a LB9 which is what I have as well. It most definatly made a difference. My next set of mods will be to open up the intake