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Full Version: 2.4 lt big four Exhaust ?'s
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JRust
I bought nice set of SS HE along with a dual tip Triad Muffler a while back. I got them from John Kelly (Ghia Specialties). He had them on a big 4 also. Just wanted some input as to wether these will be sufficient? I would like to retain my heat if possible. The carbs are 48 weber's I believe. Not sure on the jets or anything yet. Bought the engine from Craig at Camp914. The only problem is we don't have any build info on it. I figure to put it in & see how it feels/runs.

This may be a dumb question but it was built off a GC 2.0 engine. Are the spark plugs different when you build a big 4 or do you still use the stock plug & gap? Obviously this is a new arena for me with the big 4. Any advice is much appreciated. I am hoping to put it in early next month. Just getting to prepping/fixing my engine bay while it is empty blink.gif
PeeGreen 914
As to your exhaust it should be great. As to the other I have no idea.
jd74914
They should work, but will really choke the engine. If you want heat without spending a ton of cash they are your only option though. smile.gif
craig downs
The stock exhaust so way to small and your looking at trouble down the road. Being
way to restrictive your engine will run hot and will kill power. You really need to have a header with a that big of a engine
PeeGreen 914
If it is a triad it is not stock. The SSEs are perfect for a big four. I know plenty of teeners that are running just this with a big four and the Triad helps with good airflow. The weber 48s may be a bit big though. It will depend on the venturis you have in there, but most people I know that have 45s or larger are wanting to go down to 40s.
jd74914
QUOTE(Phoenix 914-6GT @ Feb 25 2008, 12:02 AM) *

If it is a triad it is not stock. The SSEs are perfect for a big four. I know plenty of teeners that are running just this with a big four and the Triad helps with good airflow. The weber 48s may be a bit big though. It will depend on the venturis you have in there, but most people I know that have 45s or larger are wanting to go down to 40s.


They really are too small. Just because other people are using them doesn't mean that they are correct. smile.gif 2.4L is a huge T4.

The Triad alone won't help that much. This engine really needs a good header, but you could make due with the SSIs if you need heat.
PeeGreen 914
Well sh!t, I guess I just don't know what to do for you 4 guys chair.gif You're right, a 2.4l 4 is bigger than I am used to seeing. I think the largest out here is a 2.6l 4 blink.gif that is using the Triad headers as it does need them. However, the 2.2s are fine with the SSEs. I would guess the 2.4 is a toss up with losing heat if you go with headers. If I remember right though the SSEs have a larger diameter than the stock HEs which do help in this case. Just lose the heat and go with headers.
Heeltoe914
Go headers, and try running a NGK BP5es plug. after run in look at the plugs check head temp and provide info to us on how it ran. Info on what you find and here while driving the plugs are a great way to tune the eng, but dont let it idel keep the revs up so you get a good reading on the plugs.
Jake Raby
The TIV is all about exhaust!! This engine is more exhaust dependant than most any other due to it's exhaust and intake port designs.

At 2.4L the exhaust is very critical to every aspect of the engine from rev range to MPG and running temperatures. I have, on many occasions seen a 20HP difference between 2 exhaust systems back to back in my lab, just last week I saw 27 HP between 3 different systems on a little 2.0L race engine.

It does sound like you have a bit of a misconfigured arrangement with those big 48mm Carbs and the exhaust that you mention. We START to use a 38mm carb at 2.7 Liters and up to that point a Weber 44 or Dell 45 always makes more power thats usable.

The largest engine I run through stock heaterboxes is my 145 HP 2270cc Daily driver spec engine. Development and direct experience has proven that anything over this needs a much more effective exhaust system and most of my builds have the Tangerine Racing system mandated.

Without proper exhaust we could never reach the insane power levels that we have today. It never ceasdes to amaze me how guys will spend thousands of diolars on induction, compression and cam/ head work only to bolt on a 300 buck exhaust and compromise the rest if the engine.

Exhaust IS everything.

BTW- reading plugs on unleaded gas is near impossible to do with any repeatability at all..
JRust
The heat is not all that critical. It would be nice but heck I usually only drive if I can have the top off anyway. Having said that I will try my SS HE first & se how it performs with the triad muffler. I really don't know that much about the engine or it's build. So really the whole thing is kind of a crapshoot. I may be wrong on the Weber 48's. They look big to me so I just guessed. I'll get the numbers of it & find out for sure.
On the plugs? Jake do you just use a stock plug? How about the gap for them? I guess I'll run what is currently in it to start & see what happens. With as little as I know about the engine I need to just get it in & see if it will start. The figure out all the fine tuning by how it runs or if confused24.gif . I'm a little over my head with it but it will be a good learning experience idea.gif
Brando
Go with the Tangerine header. He makes one with heat now.
JRust
QUOTE(Jake Raby @ Feb 25 2008, 03:08 AM) *

The TIV is all about exhaust!! This engine is more exhaust dependant than most any other due to it's exhaust and intake port designs.

At 2.4L the exhaust is very critical to every aspect of the engine from rev range to MPG and running temperatures. I have, on many occasions seen a 20HP difference between 2 exhaust systems back to back in my lab, just last week I saw 27 HP between 3 different systems on a little 2.0L race engine.

It does sound like you have a bit of a misconfigured arrangement with those big 48mm Carbs and the exhaust that you mention. We START to use a 38mm carb at 2.7 Liters and up to that point a Weber 44 or Dell 45 always makes more power thats usable.

The largest engine I run through stock heaterboxes is my 145 HP 2270cc Daily driver spec engine. Development and direct experience has proven that anything over this needs a much more effective exhaust system and most of my builds have the Tangerine Racing system mandated.

Without proper exhaust we could never reach the insane power levels that we have today. It never ceasdes to amaze me how guys will spend thousands of diolars on induction, compression and cam/ head work only to bolt on a 300 buck exhaust and compromise the rest if the engine.

Exhaust IS everything.

BTW- reading plugs on unleaded gas is near impossible to do with any repeatability at all..

SO I got a chance to go check out my carbs. Here are the numbers on my Webers 40 IDF 19 1F . I guess my estimate of 48 idfs was a little off. I just noticed the air filters seemed so big. Guess I am used to the 36's that were on my 1.7. I am looking at doing the install in 2 weeks. Hopefully I make good progress this weekend. Then the following weekend hopefully I'll be ready to put it all in. chowtime.gif
ChrisFoley
40s are small for a 2.4L. Look at the primary venturi size. The number is usually cast onto the surface near the top.
Jake Raby
Yep, 40s are too small..
You need a pair of 44s for that engine to tune and operate at it's best.
JRust
QUOTE(Racer Chris @ Feb 26 2008, 04:01 AM) *

40s are small for a 2.4L. Look at the primary venturi size. The number is usually cast onto the surface near the top.

Will do! I'll post it when I get a chance. biggrin.gif
JRust
QUOTE(Jake Raby @ Feb 26 2008, 06:21 AM) *

Yep, 40s are too small..
You need a pair of 44s for that engine to tune and operate at it's best.

I may not have a set of 44's by install. I'll keep my eyes open & get a set asap. Even if I get it up in my car I doubt I'll do much more than that. Still unsure as to the build or it's overall condition. So I am expecting some issues. I'll update here when I get closer. Thanks again for all the advice. Please don't think I am not taking it to heart. I will probably go tangerine if I get it in & I know the engine is solid. Until I do that it would be premature. I realize the engine is a little misconfigured with the carbs to exhaust. I'll get there with it eventually. I really want to have it complete & ready for summer/ late spring. SO I have time to get everything done & done right. I'm a little behind the curve but your advice helps pray.gif ALOT!
PeeGreen 914
There are a few people that have 44s that want 40s. I have seen a few people ask to trade in the classifieds. You may want to try that.
JmuRiz
Would the Dell 45s be the best carb for this size motor? If so I have a set sitting for an engine build that'll probably never happen.
Jake Raby
QUOTE(JmuRiz @ Feb 26 2008, 09:58 AM) *

Would the Dell 45s be the best carb for this size motor? If so I have a set sitting for an engine build that'll probably never happen.

Possibly, depending on what other components he uses to comprise the combo.
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