I see ads for header wrap all the time in magazines and was thinking about getting some. It's supposed to lower underhood temps. But, it is like $70 to do my headers, and the note that came with the headers said it would void the warrenty. Well, I already did that when I had the O2 sensor welded in. So, I was curious if anyone has used it and if it was any good or bad? Or, should I evven bother?
Thanks!

 

I know is works the header harder. Once wrapped, the header hold more heat like it is supposed to. The problem is, the flow creates more heat in the curves and burns out the metal. Wrapping really shorten the life of the cheaper headers. Thats why it voids the warranty.

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1992 Pontiac Firebird 350/Six Speed
1987 Toyota Pickup 383/500+ HP

 

Thats some good advice. The wrap will make the headers hold more heat than they are designed too. Thus it will shorten the life of your headers and cost you more in the long run. Besides, the underhood temp you would gain would do nothing for the performance of your engine, and isn't that what you are really after!!

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88 GTA
L98 350
700R4
3:27 axle
MODS,
Edelbrock TES headers, 2.5" straight pipe, Flowmaster 80 series, K&N filter, Accel 8.8mm wires, Bosch Platinum plugs, Wells cap and rotor button, Wells ignition module, MAF screens removed, Hypertech TB air foil, Thermomaster stage II chip, 180* Powerstat, Hypertech cool fan switch, B&M shift kit, B&M power clutch pack, B&M servo, GM fuel filter.

[This message has been edited by speed88 (edited November 14, 2000).]

 

Well I can tell a major difference in underhood temps with my header wrap. I am talking like 20-30 degrees here that can be like 5hp compared to when your pulling the hotter air. ALso it help the exhaust flow faster giving a little more hp. Remember the saying "If you want to add 10hp then find 1hp in 10 differnt places" This is one that will come into effect. Oh I have had my wrap on for 2 years and never had a problem. My Borhter has them on his to with the same header plus wraped the maifolds of his old 97 GTP and never had a problem with any car. I would recomend doing it, but we did ours off the car so we could get a much better wrap

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86 Trans Am 355 TPI Rebuilt 700R4 with Corvette servo, modified valve body, and a B&M Torque Converter (2000 rpm stall w/ lock up), 87 350 block bored .30 with new crank, bearings, rings, and magnafluxed rods. Reworked 305 heads with 3-angle valve job. Added in the rebuild was an SLP TPI cam, BBK 58mm Throttle Body,SVO 24# injectors,MSD 6A, Hypertech Power Coil, 1.5 Crane roller tipped rocker arms, SLP Intake Runners and Port matching in upper intake including fully ported plenum, TPIS adjustable fuel pressure regulator @ 46psi, Hooker shorty style headers w/ Thermotech heat wrapping, Custom 3” exhaust with Flowmaster muffler and chrome quad tips, Hypertech Thermomaster Computer chip, K&N open element cone filter on modified MAF per TPIS specs, MSD Wires, removal of A/C hardware and a 1LE firewall cover installed. Also there has been a PST front suspension kit with Hotchkis strut tower brace
http://geocities.com/SunsetStrip/Garage/9548/kyle.html

Kills:
95 Talon TSI, 96 Probe GT, 91 T/A L98, 89 RS, 86 Mustang GT, 88 Mustang LX 5.0, 92 Thunderbird V8. couple or ricers that I think were Civics or Preludes not sure what year, 95 Celica GT-S, 94 Chevy 1/4 ton 350, one of those NASCAR F150's

 

Actually the header wrap will help make power in two ways.

1. Keeping heat in the exhaust system will help maintain the velocity of the exhaust gases which aids scavenging and removes restriction downstream.
2. Cooler temps in the engine bay mean cooler air into the engine(rest your palm on the TPI plenum sometime after the engine's been running two or three hours - observe the nice parallel burn marks on your hand caused by the plenum's "cooling fins"). The common formula for lowering intake temps is: a 10 degree decrease in temp will yield a 3% increase in hp.

Header tape has a bad reputattion for two reasons:
1. The aforementioned burnthrough caused by using the tape on cheap(read thinwall) headers.
2. Improper installation and can allow moisture to get between the tape and the headers. The moisture gets trapped and causes corrosion(rust).

If you have thick guage, coated or stainless, headers neither of the above should be a problem. As long as you take care to apply the tape properly.

as an alternative you may want to look at having a "thermal barrier" coating applied to the inside of the header tubes. this will doubtless be more expensive than tape, but should be more effective as the the heat is kept away from the inside of the tube. offhand, the only place I know of that does this type of coating is Bohacz Advanced Technologies(yup, that Bohacz). I believe he's located in New Jersey, but I don't know the address. If no-one here knows the address, you may want to drop a line to Ray at "GM High Tech Performance" magazine.

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He who hesitates,... is lost!

 

There are several places that coat headers: JetHot, Paul Barry (I forget his URL), among others I forget at the moment. Most of these companies will coat the headers inside and out, at least I know the 2 I mentioned do. Another possible problem with header wrap is if you get a fuel or oil leak and it gets on the wrap, it'll start a fire. I know of a guy (Tom Byrne) that had his car go up in flames because of this...

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Greg Westphal
'87 IROC 305TPI/A4

 

Most headers coating are only as corrosion prevention or dress-up. Though I imagine there more places than just BAT doing thermal barrier coatings.

another idea i've been playing with is having thermal barrier applied to the plenum, runners and underside of the lower manifold. should lower intake charge temps, but really won't do anything for underhood temps.

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He who hesitates,... is lost!