backformore
New member
Any opinions on this header? It's 1/3 the cost of a Skunk2 or equivalent. Trying to find the sweet spot for cost vs ultimate performance with bolt-on engine parts.
Thanks.
Rory
Thanks.
Rory
DC Sports 4-1
- Thread starter backformore
- Start date
backformore
New member
Thanks Greg. Just the sort of first hand info I was after. Are you using a 4-1 or a 4-2-1?
ITA_honda
New member
4-2-1
darthmonkeyIT
New member
I did some research into headers a few months back for the CRX.
A 4-1 header will generally give you more high end power and is better for high RPM applications.
A 4-2-1 will give you more low end and mid range torque.
Exhaust pipe size also matters. Smaller diameter pipe will increase your back pressure which helps on low end torque but suffers at higher RPM's. Vice versa for a larger diameter pipe. Most Honda-Acura (early 90's 4 cylinders) exhaust write ups I have seen recommend either a 2.25" pipe or a 2.5" pipe depending on tuning levels. A 10/10th's engine will be putting out more exhaust flow for more of its operating cycle and can make more use of the larger diameter pipe.
So when changing headers make sure to look into what the effects are going to be on the system. A higher flow rate (4-1 header) could be hindered by using a smaller diameter pipe thus negating its added flow rate.
Note: This is coming from an internet junky who reads forums, tuning articles, and others personal experiences to make informed (seems like a good idea) choices. Take what I said with a grain of salt. Ask some experienced exhaust techs.
If you already knew what I said then well someone else one day may find this useful.
-Sean
A 4-1 header will generally give you more high end power and is better for high RPM applications.
A 4-2-1 will give you more low end and mid range torque.
Exhaust pipe size also matters. Smaller diameter pipe will increase your back pressure which helps on low end torque but suffers at higher RPM's. Vice versa for a larger diameter pipe. Most Honda-Acura (early 90's 4 cylinders) exhaust write ups I have seen recommend either a 2.25" pipe or a 2.5" pipe depending on tuning levels. A 10/10th's engine will be putting out more exhaust flow for more of its operating cycle and can make more use of the larger diameter pipe.
So when changing headers make sure to look into what the effects are going to be on the system. A higher flow rate (4-1 header) could be hindered by using a smaller diameter pipe thus negating its added flow rate.
Note: This is coming from an internet junky who reads forums, tuning articles, and others personal experiences to make informed (seems like a good idea) choices. Take what I said with a grain of salt. Ask some experienced exhaust techs.
If you already knew what I said then well someone else one day may find this useful.
-Sean
backformore
New member
Thought I'd add this. Since I've started my research, Skunk2 has come out with their Alpha series of headers for the B engine. They say it is the same design with some "manufacturing changes" to allow them to offer them for less money. Seem like they are available for a little over $400 and they have a 2.5" collector.
My opinion is that this is now the sweet spot. I will be keeping my eye out for a deal on one of these.
My opinion is that this is now the sweet spot. I will be keeping my eye out for a deal on one of these.
mossaidis
New member
Rant: I was on d-series.org ALOT back in the day, even got me some H-T. The understanding was that two headers proved to be the best for the D-series engine, and some argue even the B series. Both Hytech and SMS-P offer custom designs and off-the-shelf. Last study I saw showed that the off-the-shelf Hytech would produce about 1whp more than the SMS-P on a D16a motor with simple I/H/ECU mods. Hytech went for about $1400, which is $700 more than the SMS-P. That was 2 years ago and I am sure other brands have joined the best of breed header market. DC was, perhaps still is, considered the best value. Yet, I don't see much of apple-to-apple comparsions these days, though I don't read tuner mags anymore. I have a custom built 4-1 SMS-P header currently. It was purchased used, the original owner had it coated by swain and designed it for a medium street d16a motor as it does have a 2" collector.
I have a custom built 4-1 SMS-P header currently. It was purchased used, the original owner had it coated by swain and designed it for a medium street d16a motor as it does have a 2" collector.
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For what its worth, I just purchased a Alpha series for my type R to replace what looks like a skunk clone 4/2/1 with 2.5" collector. As for exhaust, we run a 2.5" straight pipe with turn down having a 24" cherry bomb at the end.
http://www.summitracing.com/parts/IMM-87529/ The pipe ends before the fuel cell and it has both a turn down, and I install a deflector so to reduce the chance of exhaust heating the tank.
Something I do is put a piece of tin between the downpipes and the block to prevent the header from heating the block. I keep the vertical downpipes unwrapped to prevent really high temps from causing cracking. I do wrap the lower downpipe where it passes under the oil pan to reduce heat transfer to the pan because its really close.
A final note is to flange and bolt everything,use a flex joint at the end of the header and do not forget to install a hanger from the engine to the header. Most header failures are due to non support of the header from the engine. I use the stock rubber hangers for the pipe, but I also put a metal strap under the pipe to prevent the pipe from dropping in case you bottom the exhaust out and it strips the hangers away. This approach has been bulletproof on CRX's, Del Sols and Integra's.
http://www.summitracing.com/parts/IMM-87529/ The pipe ends before the fuel cell and it has both a turn down, and I install a deflector so to reduce the chance of exhaust heating the tank.
Something I do is put a piece of tin between the downpipes and the block to prevent the header from heating the block. I keep the vertical downpipes unwrapped to prevent really high temps from causing cracking. I do wrap the lower downpipe where it passes under the oil pan to reduce heat transfer to the pan because its really close.
A final note is to flange and bolt everything,use a flex joint at the end of the header and do not forget to install a hanger from the engine to the header. Most header failures are due to non support of the header from the engine. I use the stock rubber hangers for the pipe, but I also put a metal strap under the pipe to prevent the pipe from dropping in case you bottom the exhaust out and it strips the hangers away. This approach has been bulletproof on CRX's, Del Sols and Integra's.
mossaidis
New member
The d-series header from PLM is not compatible with PS and AC components, otherwise it looks like a sweet deal.
https://www.privatelabelmfg.com/product_p/plm-hd16-header.htm
https://www.privatelabelmfg.com/product_p/plm-hd16-header.htm