Benefits of upgrading the manifold/exhaust?

[Pistacchio sprint 72]

For a Sprint FHC, would it be a good idea to upgrade the exhaust from standard bore to Fast road specs?

What can you expect?

[rgh0]

it will not hurt and you may get a bit better mid to top end torque and a bit more top end power but you will most benefit if you some other development work on the engine to match

cheers
Rohan

[Pistacchio sprint 72]

I don't intend to touch my engine.

Will the sound change? flames? bangs?

The question is, is it worth the bucks?

[gherlt]

>The question is, is it worth the bucks?

How much would you spend ?

[Pistacchio sprint 72]

Also i do?t want to cut footbox or do heavy modifications to fit it.
So a big NO for the race one.

Do TTR , miller , keveldon have the same supplier ? Or do the different fast road manifolds available out there are all different?

[adigra]

The reason I'm installing a fast road exhaust is that the rolling road showed my engine being suffocated by the standard system. On the bench my engine (which is built to Q420 spec) produced 145BHP on 97 octane, but in the car with the standard exhaust the best we could do was about 110 at the flywheel, with the power flatlining at 5300rpm (the power stayed roughly the same from 5300 to 6500, while on the bench it kept steadily climbing). I am not expecting to achieve the same power in the car as we did on the bench with a naked engine, but I'm hoping the larger bore exhaust will free it up to get past that power plateau. The fast road systems are rated for up to 160-165bhp, so I am hopeful and curious to see what it'll achieve. I'll have it back on the rolling road next month and we'll see.

So, from my observations, I would think most engines will benefit to some degree from a freer exhaust, but higher their tune greater the margin.

To answer your question regarding different suppliers. Kelvedon and TTR fast road manifolds are definitely different (their race systems look very similar though). The TTR one is modelled after their race manifold with equal length pipes, and it's mild steel, while the Kelvedon is more similar to the standard, just in larger bore, and in stainless. As you've noticed in my thread, I am fitting the TTR system, and from the replies I received it doesn't need any modifications short of the cutout in the chassis, which my car already had, I'm just having it strengthened as recommended.

Regards,
Adi

[Pistacchio sprint 72]

Back in the subject!

I like the Kelvedon manifold because it is in stainless steel so it's a shiny piece of kit. However you re right Adi, it is looking like the original manifold and the pipes have not the same lenghth

While the TTR, with equal lenghth pipe might be better balanced for the engine exhaust gazs, but looks dull in picture. Mild steel... why choosing mild steel? it can rust right?

[rgh0]

Stainless Steel manifolds are made of thinner material and tend to be noisier and can crack with vibration. Mild steel manifolds are thicker and quieter and more tolerant of vibration but can rust overtime and don't look as nice even when painted.

Mild steel manifolds with ceramic coating inside and out don't rust and are quieter still and reduce engine bay heat also and are the best option I believe. I prefer the aluminium metal finish coating but you can get in other colours and style.

cheers
Rohan

[Pistacchio sprint 72]

Thank you Rohan.
The coating add to the total price...

[rgh0]

It cost me A$235 to have my TTR manifold locally coated a couple of years ago after I shipped it from the Uk

cheers
Rohan

[adigra]

Thought to update this as I had the car set up on the rolling road after having the TTR system fitted. We didn't do any power runs, so I can't tell you the ultimate power, but during the setup the reading at 5800 RPM was 90bhp at the rear wheels with the standard system, vs 96bhp with the new. The biggest difference was beyond that though, as before the power flatlined at around 5300, and now it keeps climbing well beyond 6k. I am very happy with that.

[Uboat]

With TTR fast road You can say hello to a lot of noise from rear silencer, in addition to useful extra output. Earplugs will be a necessity on highway trips.
Ulf

[twincamman]

aaaa????? pardon?????? would you please repeat that????? ed

[adigra]

With TTR fast road You can say hello to a lot of noise from rear silencer, in addition to useful extra output. Earplugs will be a necessity on highway trips.
Ulf

It's certainly louder, but I wouldn't say a massive amount. The biggest difference I notice is when driving close to walls or parked cars as the noise bouncing back is much throatier. Now that we've dialled out all popping on the overrun, it sounds almost civilised.

[Pistacchio sprint 72]

Noisy is fun.
Keeps you alive in trafic