MikaylaHunterCig

Anyone tested all the popular aftermarket 496 exhaust options ?

Outside of CMI what is the best for the buck ?

Cost ?

LAKESIDE RESTORATIONS

Outside of that, Stainless Marine & Dana. We sell & install all of them. It depends on what you want & want to spend. They all will add some pep, but they almost never bring the 5-7 mph that some mfg's claim.. It is truly more like 1-3 best case scenario the majority of the time depending on boat.. Jamie / Lakeside

Undertaker

Installed Dana exhaust on my 05 Donzi 22 classic 496 HO saw noticeable mid range punch, about 2 mph on top end, up one pitch in the prop...price was reasonable for performance gains... purchased from Jaime @ Lakeside, he also did the install.. Good Luck

Undertaker

tblrklakemo

Save the exhaust for when you have intake mods too. All options are too much money, IMO, for very little gain over stock manifolds. Pull your risers and polish them up if you want bling.

bowtye8

The dana website has some decent info and dyno sheets for thier new 496/HO manifolds. My only grip would be to perform a before on their dyno.
http://www.danamarineproducts.com/in...er_HighRes.pdf
Maybe Raylar will chime in.

They have after results. 496=423HP/534tq and for the HO 478HP/548tq. Their sheet shows the HO is still making good pwr at 5000 RPM.
Would be nice to see if the stock 496HO is at 425HP?? on the dyno it may be pumping out 450HP?????????

The price is beater compared to the CMI's.

Raylar

Bang for the buck and real world results we at Raylar like the Dana Flo-Torque exhaust. The kits are complete, easy to install and they really do produce the power and torque levels that Dana claim, cause Raylar did the dyno testing on our dyno with bone stock 496Mags and 496MAGHO's. To start with the 496Mag will consistently produce about 375-385 HP in stock trim and the 496MAGHO's produce between 421 to 432HP stock on our dyno. Unbolt the stock manifolds and bolt on the Dana header manifolds and the results will be what they show.
The Dana's can be provided polished or powder coated in color and about the only drawback is they are a bit wider than stock manifolds, about 3/4" per side, so on a tight twin install they could be a problem if the engine hatch ram is between the motors. We have seen some twin engine users just remount their ram a little forward of the motor and create the extra room.
CMI's headers are good headers and are sexy looking in polished stainless and they will make about 5 hp more at 5000 rpms than the Dana header manifolds. At twice the cost for CMI's per engine and about twice the time to install the CMI kit versus the Dana kit, you can see why we lean toward the Dana's. Don't get me wrong, the CMI's are great headers and they make slightly more power, +5HP.
Dana also offers their header manifolds hard anodized and powder coated for the boaters who spend all their time in salt water.
As for the other headers on the market, such as Hardin, Eickert, Lightning, Stellings we have seen them used successfully in stainless on 496's and power levels on all are similar. These are all true 4 tube headers.

As for just using upgraded exhaust manifolds (non-header type) you can see a slight increase in power over stock manifolds with usually about 15-20HP max over stock on stock engines. Remember that these units as manufactured by Stainless Marine, Eddie Marine, Revolution, Gil and certain models of Imco and others are short runner manifolds with larger diameter single pipe risers and not a true 4 tube header (from exhaust port of head to collector in riser) so on normally asspirated engines they will not scavange quite as well and therefore will be down on power as compared to Dana, CMI, Lighting, Hardin, Imco Powerflo 4 tube and Stellings and such. These after market exhausts all tend to be good products from good companies they are just an older, simpler designs. Some such as Eddie and Hardin have taken the time to actually provide these manifolds in kit form so as to make the conversion less painless and not a custom job it can become if one converts the exhaust on a 496 without all the adaptor brackets and fittings.
If you plan to add addtional upgrades to your 496's like our kits or aftermarket superchargers in the future, invest in the good header type exhaust now because with increased power levels the true header will become even more important with higher horsepower levels produced from a deeper breathing engine.
Also remember most no two boat model exhaust routings are the same and things like double s-pipes, captains call-silent choice, corner exit exhaust routings and such will scrub off some power gain froma aftermarket exhaust. The turns, bends, junctions, convolutions all affect the overall effectiveness of the exhaust.
Raylar, Bob at Full Throttle , Tyler Crockett and others have seen and can demonstrate in actual engine testing that water being introduced in the exhaust path prior to the actual transom tip can and will drop horsepower anywhere from 15-25HP versus just a dry exhaust on most 496 models.

This now concludes aftermarket exhaust for 496's -101 class for all those who needed to know but might have been hesitant to ask!

Good Luck with whatever exhaust upgrades you choose to make and know any improvement is an improvement.

Best Regards,
Ray @ Raylar

bobl

Here's a link to dyno testing we did on the 496.

http://fullthrottlemarine.com/496%20...%20Article.htm

bowtye8

Excellent write up on the 496HO with Dana exhaust and then the Raylar kit.
What would be a good qoute for Dana and the Raylar kit about 10K per engine?

bobl

10k is pretty close for parts, not counting labor and tax. Figure another couple of grand per engine if you pay a shop to do it.

Keith Atlanta

CMI eTops are the best bang for the buck followed by Danas.