Log style header vs tubular header test results
 

I happened across this video this morning regarding testing a log style turbo manifold vs tubular header turbo manifold and was quite surprised at the results. The log style beat the tubular header handily! Log manifold made boost quicker and more of it

Tubular header: 603 hp and 560 lb/ft
Log manifold: 710 hp and 668 lb/ft

Test done by Richard Holdener on a 5.3 LS
https://youtu.be/dhK-lWFW7Jk?si=pAPcfULckULK1t2Y

I had the same results with my motor. It really improved the spool time .. So being it spools quicker i see more torque at the lower rmps ..

I just ordered 2 of those turbos .

I was meaning to visit his website to check them out. I had no idea they would be so affordable. Curious, are you going to run them in a twin configuration or are they for 4 cylinder projects? If these are sized right for twins they are a great deal!

https://richardholdenerperformance.c...ournal-bearing

No, I have a twin turbo car with GT45's on it. I couldn't stop thinking about how fast it would spool being he said that the gt45 spool slow compared to these. My car now spools fast so this is going to be really interesting to see what these do.

These are cheap compared to the $2600.00 precision turbo on the 4 cylinder. They are more than the gt45s I bought though. I didn't buy from him because he's just getting into selling them and figured it would take longer for him to get them shipped. He even said on his podcast that he's not fully going yet with selling them ..

Yeah, I just looked at the link you sent. Mine will be here next week. His site says late April... Not that it's a big deal but it was 10 bucks cheaper where I got them ..

Can I ask where you got them? I’m looking for a larger single around 88mm and I’d like to see what they offer. I think a single would be easier to package for me. I’m only wanting to make between 900-1100 hp. To package twins I’d have to move some of my hydroboost and catch can lines. Not terribly hard but you run out of room quick when you are trying to cram an intercooler, cold and hot pipes in the engine bay.

Do you have any pictures of your twins setup? I don’t think I’ve ever seen any posted.

Yes, I got them on eBay . https://www.ebay.com/itm/265755232392 Hopefully this link works.

You should get the gt42 like Richard tested. He said it's good for 1200hp.

No ive never posted it here . Ill see if i can get some to load up here of my twin setup

Here's 2 that I found ..

Just watched the test between the 800+ HP GTX3584 and the 1200-HP G42-1200. I’m definitely looking into the G42. I do have concerns that the G42 may have too much back pressure with my combo though. It will probably end up in the 461” - 466” range. I’m current at a 4.285” bore but will be reducing the stroke from 4.21” to 4”. It ain’t no little 5.3 LS :pound:

https://youtu.be/FDij2zpr3jo?si=_Mx8XENCoqNdHuQK

imo, you said you're looking to get into the 900-1100hp rang. That turbo should work. If you want over 1100hp then you probably should find something with a bigger turbine wheel. I've talked to Richard on the phone in the past. He's a cool guy. Try messaging him and ask him what he thinks about your concerns with your motor being too big. I think I remember him saying that the gt42 would be perfect for a 454 big block. I know that your motor is bigger, and I can see why you're concerned. If you're just going use your car for street driving with this turbo 900 is a lot of steam imo and I bet with this turbo it would be a light switch lol. I'm going to check out this video. Thanks for sharing it..

When i first put together my turbo setup, a told a friend I wanted to try a half turbo setup, one side n/a header and one side to feed the turbo. He swore it couldn't be done but I argued it could. I'll have to send him this video.

That was a pretty cool video, But I wonder with only one side taking all of the backpressure if it could eventually hurt the motor down the road..

Have you had a chance to swap out the turbos? Any feedback?

yes, I got them both on.

The spool time is cut at least in half.

The power seems the same on top, but it comes on sooner with less throttle which is exactly what I was going for. I'm 100% happy and glad that I did the change. So glad I saw Richard's video. I haven't turned it up yet, I'm expecting nothing less than more improvement.

How's yours coming alone?

I wanted to wait for your feedback on those turbos before making my decision. I think they will be a great fit for my combo and easier to package. I'm going to look around to see if I can find a mirror set.

I'm hoping to dig into the hot side fabrication in the next few weeks (I coach youth sports and All Stars is taking up my free time at the moment). I have a set of the 2.5" log manifolds from Stainless Headers. I'm running power steering (Hydro-boost) and used a custom remote tank set-up to give adequate room for the driver side manifold (hopefully lol).

Oh, ok cool, Yeah, the 2.5 will work very well. LMK how you make out. I look forward in seeing what you come up with.

Check put these turbos...

https://www.ebay.com/itm/13501091034...9ef6d69000d5a2

Fitting these turbos was very easy. It was much easier to fit them compared to the GT45s I had in there. I was surprised how small there are.

I really appreciate the recommendation! That’s a great price for twin ball bearing turbos. I’m 99.9% sure I’m going with those. I’m going to reach out and see if they offer them in a V-Band instead of a T4 without the cost doubling.

No problem, just double check on what you're getting before you buy.

LMK how you make out ..