20v exhaust

[kolczak]

i'm right in the middle of doing a blacktop swap and i noticed that i'm gonna need a downpipe fabricated to finish my exhaust but i was thinking about going with an aftermarket header and downpipe. i was wondering if anyone has had good luck with some and since it is a blacktop will it still fit even though that motor came out of a front mounted car or if i will run into problems.
thanks

[tjmr2]

I used a 16v TRD header and modified it since I already had it and my exhaust just bolted up once I fabricated and had tabs welded on. (16v & 20v port spacing is the same but the bolt - stud holes are different)

I have heard that the 20v header is hard to beat, if you are starting with what used to be stock exhaust I'd have a muffler shop fabricate a down-pipe and work your way back from there.

And the BT 20v header came with a heat shield.

[kolczak]

ok. thats probably my cheapest option too. thanks for your help i'll just have that done.

[Mista 2]

Tjmr2 is correct about the exhaust ports for a silvertop 20V but the blacktop has larger exhaust ports. I was lucky with my blacktop as it came with custom headers and they still fit even with my starter on the exhaust side.

As for going for aftermarket headers made for a blacktop that will be ok if you have mounted your starter on the intake side.

[Raptor13x]

I'd definitely just have an exhaust shop make up a custom piece- that's the easiest and most likely cheapest way to go.

[te51levin]

Do you have a 20V upper header? I am building a 20V adapter pipe now and may build more if I can get the flanges done cheaply enough.

[kolczak]

yeah i have the upper header. that'd be awesome if you could give me a price. i'd be very interested.

[te51levin]

Here is the downpipe and catalytic converter I built next to the customer's hacked-up SC downpipe and undersized cat. I am still waiting on the header outlet flange (had to find a new source as the first shop was smoking crack) but other than that it's done. I can build you one like this for about $150-160, maybe less if there is reasonable volume.


My stuff is 100% bolt-in...

[fastrax203]

Originally Posted by te51levin

Here is the downpipe and catalytic converter I built next to the customer's hacked-up SC downpipe and undersized cat. I am still waiting on the header outlet flange (had to find a new source as the first shop was smoking crack) but other than that it's done. I can build you one like this for about $150-160, maybe less if there is reasonable volume.
http://www.carpron.com/multisite/d/231656-2/20vdp.jpg

My stuff is 100% bolt-in...

So, will that be $150-$160 for a bolt in product with the 20v flange and everything? If this is true where do I send money for one?

[te51levin]

I'll update you on that when I get the flanges and know that this project is fully cleared for takeoff

[te51levin]

A few more pics. I got the first downpipe done!











For those who are interested, I can make these for you too. This is 100% bolt in downpipe that couples the 20V header to the AW11 catalytic converter inlet flange. I have three more 20V flanges and enough supplies to build one more downpipe immediately, so I'm making one for fastrax203 right away, and I can have more supplies here within a week or so to build more if anyone else is interested. I can supply it with a two-bolt Toyota oxygen sensor flange or a regular 18mm threaded bung, whichever you prefer. I can put a flat flange like this one on it, or a grooved flange to take a standard Toyota crush gasket - that will make this a bolt-on to the SC cat inlet. The first few are going to look a little boogery (I'm a parts guy with a welder, not a pro fabricator), but my stuff fits and works right. Who needs one?

[fastrax203]

Originally Posted by te51levin

For those who are interested, I can make these for you too. This is 100% bolt in downpipe that couples the 20V header to the AW11 catalytic converter inlet flange. I have three more 20V flanges and enough supplies to build one more downpipe immediately, so I'm making one for fastrax203 right away, and I can have more supplies here within a week or so to build more if anyone else is interested. I can supply it with a two-bolt Toyota oxygen sensor flange or a regular 18mm threaded bung, whichever you prefer. I can put a flat flange like this one on it, or a grooved flange to take a standard Toyota crush gasket - that will make this a bolt-on to the SC cat inlet. The first few are going to look a little boogery (I'm a parts guy with a welder, not a pro fabricator), but my stuff fits and works right. Who needs one?

Thanks Aaron, I'd like an 18mm threaded bung instead, I'm gonna use a '96 Camaro O2 sensor to be cost effective. I also don't need a flex section, but if this has no effect on price than keep it in there, I also don't need a catalytic converter flange. Did I mention YOU ROCK?! IF NOT, WELL YOU DO

[Raptor13x]

That actually looks pretty good. What diameter pipe are you using?

[te51levin]

Thanks! The secondaries are 1 3/4" OD, which fits the 20V header outlet holes just perfectly. The stock secondaries are 1 5/8" OD. Main tubing is 2 1/4" OD. I picked these sizes because they'll allow a little more airflow than stock, but mostly because I wanted a smooth flowing transition between the primary collectors and the secondary pipes. The smaller 1 5/8" secondary pipes jut loosely into the primary collectors producing a sudden and jagged step from a larger pipe to a smaller one, which is never good for airflow. 2 1/4" is adequate for most 20V engines and mates well with the SC cat and muffler, and it's easy to build bolt-in replacement cats (I have a jig for that too) on 2 1/4" blanks that will bolt to the stock downpipe and muffler and/or anything I build.

[kolczak]

i would love to order one asap. how much are you charging?

[te51levin]

For this first batch I am charging $150 plus shipping, which is $10-15 depending on your location.

fastrax203: your pipe is done! I made it a little differently than the first one, but as I mentioned, I like it better in some ways. Here are the pics:









You can pay me via PayPal using my personal email address. Thanks man!

Oh, by the way - the downpipes fit into the header snugly enough that you may not even need gaskets. You can try it without and let me know how it seals up.

[curvesrgood]

Nice, that's exactly what I'm about to have to make for my 20v header. Just had Dad check out the flange so he can have me one made... . I'd buy one of these and save some trouble, but I live in race country and everything is about half the cost (or less) of most shops in the country around here. Nice work, looks like good quality!

[te51levin]

Originally Posted by curvesrgood

I live in race country and everything is about half the cost (or less) of most shops in the country around here.

No worries. I found pretty good pricing on my supplies and they still make up the bulk of my price.

[curvesrgood]

Yeah, I just thought that what I said might have sounded like I thought yours were expensive... didn't mean to imply that at all, actually that is a really good price for a good b-pipe, but I'm just lucky because I have friends at lots of shops around town and dad has spare metal for things like flanges from over at the custom machinery shop he works at. I really like the look of yours, hopefully whoever I let weld mine (if I don't tackle it myself... I might, good project and I've had a hankering to get back to welding again) doesn't botch it. I guess if I do it, I can blame myself if it ends up looking like one of those monkey's with the huge red behinds. I also learned not to use huge pipe like Dad did on his S/C... he might as well not have put an exhaust on the thing, lol. My S/C with an exhaust leak isn't as loud as his! By the way... this 20v exhaust header... will it work on S/C cars as well? I was initially planning on putting my 20v header on the N/A 16v out back, but it crossed my mind it might fit the S/C and would probably net me more power on that car with all the modifications and boost.

Here's an example of how crazy cheap SOME things are locally here... my buddy took his radiator from his 92 in to a shop in town because it started leaking... they took his side tanks, put in a 4 row center and essentially made him a race quality radiator for somewhere just under 50 bucks out the door! Porting and polishing around here is fairly cheap too, so I'll have to take advantage of that for the 16v head I've got sitting around with the 3 angle valve job already done to it.