| Moderated by: Greg Fletcher | ||
| Author | Post | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
Dakota123 Member
|
I think I understand that only later JH engines ended up with cast iron exhaust manifolds. Somehow 10628, a Mk1 from 1972, has a cast manifold. (Not noted in the service records, of which I have every one up until about 1990.) I'm finishing up my 2.2L, should be ~200 hp trim when all is said and done, and wondering if I'll be leaving much on the table by not going to a header. The cast manifold has been trouble-free, and doesn't seem like a horrible design, really. TIA |
|||||||||
|
Esprit2 Member
|
I don't know which cast manifold was used on the JH, but the one used on the Lotus 907 was actually very free flowing and efficient. A good tuned length tubular header could still deliver more horsepower, but not much. On the order of 3-5 hp more. Not a big deal. Regards, Tim Engel |
|||||||||
|
Dakota123 Member
|
Thanks, Tim -- from what I've seen from online images, it looks like the same part, or very similar - 1 and 4 joined and 2 and 3 joined, with separate tubes running down to a 'Y' |
|||||||||
|
Brett Gibson JH5 20497 Member
|
This is the later version of Delta's header, really has a nice free flow. http://www.deltamotorsports.com/products/pg15d-jensen-healey-headers.html |
|||||||||
|
Dakota123 Member
|
I may get it, or the one from the club store, just because they look so freakin’ cool — but then again, you can’t see it when it’s installed... |
|||||||||