1UZ FE in SFA Hilux Exhaust system help needed

[Blitzkrieg]

Good day gents.
I need some comments regarding my Hilux Lexus exhaust system.

Ceramic coated branches are being made with stainless steel free flow.
I need to know what tipes of pipe to use.

Options:
1. Single 76mm pipe from front to back or
2. Two 63mm pipes next to each other from front to back.

I want the V8 to sound classy (not like a backyard hotrod).
What will the difference in sound and performance be between the 2 options?

Any other ideas and facts are welcome!!

[MOFASA]

Good day gents.
I need some comments regarding my Hilux Lexus exhaust system.

Ceramic coated branches are being made with stainless steel free flow.
I need to know what tipes of pipe to use.

Options:
1. Single 76mm pipe from front to back or
2. Two 63mm pipes next to each other from front to back.

I want the V8 to sound classy (not like a backyard hotrod).
What will the difference in sound and performance be between the 2 options?

Any other ideas and facts are welcome!!

Try getting hold of A VIPER exhaust branch near you and they will be able to tell you all the facts......

[Hangover]

I believe you will lose a too much back pressure as your 1UZ is not turbo'd. Mark Watson is going to use 2 x 57mm pipes with a balance pipe which gives you a nice sound. For maximum power and torque 2 x 57 that go into a single 63 for the non turbo 1UZ motors was the advice of Jean of Dutch Auto.

[swartvark]

I believe you will lose a too much back pressure as your 1UZ is not turbo'd. Mark Watson is going to use 2 x 57mm pipes with a balance pipe which gives you a nice sound. For maximum power and torque 2 x 57 that go into a single 63 for the non turbo 1UZ motors was the advice of Jean of Dutch Auto.

Dis hoe ek dit ook verstaan het.

[Hoppy]

I use two 50mm pipes from the branches to the first box, a single 63mm pipe to the second (76mm) box

The second 76mm box must be as close to the back as possible, i fit a 120mm round box behind the mudflap in the top cavity with a 45deg bend out the back.

When we did the first one about 6 years ago, the client wanted the twin pipe setup, it sounded like a breakdown truck, the rear pipes were made smaller and we went for a single midle box, still noisy, but we gained about 8kw.
The third try was a single rear box, much quieter and we gained another few kw's
Finaly the system was rebuilt as above, we gained a lot of midrange torque with the 50mm front pipes and yet another 7kw, so since then this is the way we do it.
This system is silent on normal driving and gives a nice deep v8 roar at full throtle without resonating.

[Hangover]

I use two 50mm pipes from the branches to the first box, a single 63mm pipe to the second (76mm) box

The second 76mm box must be as close to the back as possible, i fit a 120mm round box behind the mudflap in the top cavity with a 45deg bend out the back.

When we did the first one about 6 years ago, the client wanted the twin pipe setup, it sounded like a breakdown truck, the rear pipes were made smaller and we went for a single midle box, still noisy, but we gained about 8kw.
The third try was a single rear box, much quieter and we gained another few kw's
Finaly the system was rebuilt as above, we gained a lot of midrange torque with the 50mm front pipes and yet another 7kw, so since then this is the way we do it.
This system is silent on normal driving and gives a nice deep v8 roar at full throtle without resonating.

Thanx for the good advice hoppy! I asked mark to fit me 2x57mm pipes with a balance pipe as a want to fit a long range tank later on my cruiser and he says its difficult to get the pipe in the... will this work ok or should i rather go for the single end piece? As you said this will give +- 7kw gain?

[swartvark]

I use two 50mm pipes from the branches to the first box, a single 63mm pipe to the second (76mm) box

The second 76mm box must be as close to the back as possible, i fit a 120mm round box behind the mudflap in the top cavity with a 45deg bend out the back.

When we did the first one about 6 years ago, the client wanted the twin pipe setup, it sounded like a breakdown truck, the rear pipes were made smaller and we went for a single midle box, still noisy, but we gained about 8kw.
The third try was a single rear box, much quieter and we gained another few kw's
Finaly the system was rebuilt as above, we gained a lot of midrange torque with the 50mm front pipes and yet another 7kw, so since then this is the way we do it.
This system is silent on normal driving and gives a nice deep v8 roar at full throtle without resonating.

I'm playing around with Swartvark's exhaust system a bit.
1st: I changed it to dual 50mm pipes with an X pipe under the gearbox.... . by the rear wheels the 50mm pipes become 63mm with a big volume round box on each just before the tips.
It sounded okay, but was resonating by the X pipe when I take my foot off the gass.

2nd: I cut out the X pipe, so same as above but without X pipe. LOTSA crackling noises out the back....horrible.

3rd: I the fitted a resonator on each pipe, by the gearbox, where the X used to be. The sound was acceptable when driving slowly or a small rev, but when under load it sounds like a VW Beetle with one dead spark plug. No good.

NOW......My next step will be to fit a +-400mm long twin in and twin out box directly behind the resonators. My thinking is that this would serve as a "balancing pipe" an muffler combo??????
If it sound good I will dyno the vehicle again to see how it compares to before I started messing around.

If it sound bad or have poor dyno results I will put a Y pipe after the two 50mm resonators into a single 63mm up to the rear wheels and then another Y into the two 63mm pipes with their boxes just before the tips.
I guess I will need a muffler on the piece of single 63mm pipe?

Any input from you guys??

[Mr_B]

I would suggest taking your bakkie to Roddey at Powerflow Bellville. They've done many of these Lexus exhaust systems and know exactly what works and what doesn't... else your school fees bill could get expensive!