Hey. Have question. So. I had a mx6 and mazda millenia atx. And I am driving long distances, lets say 1500 km without any stop just for filling up gas. And I noticed that after 1300 km running both cars looses power. So now I have a Prelude and I would like to know how to make car run long distances without any damage to the engine. How to increase life of it. How to upgrade engine for long distances. Oil cooler? Larger radiator? I already place bigger radiator, extra fan with switch which working independent. Sry for my english. Any help would be appreciated

 

Forgot to mention that engine has:
# New 4 layer steel head gasket
# Head milled 1mm
# New head bolts
# 3 inch exhaust piping, cat delete
# Ported head and manifolds
# New valve stem seals
# New timing belts
# Adjusted valves
# CAI

 

Your first step would be to figure out what is actually reducing power, and how noticeable is it.

My first guess would be heat soak of the intake system, which could be helped by eliminating any coolant lines to items such as FITV or IACV, and using a thick thermal gasket such as Hondata. Also deleting or blocking the EGR system.

Keep in mind that all of these things can have an impact on your emissions, and possibly fuel mileage.

You could also look into heat wrap on the exhaust system in the engine bay, using foil wrap or such to block heat going to the intake etc.

If you are still using stock fuel injectors, it could be worthwhile to switch to a newer Bosch EV14 style of injector, and get the car well tuned for all of the modifications as well.

Last thought is to ensure that the fuel pump and fuel filter system is in good shape, as if it runs hot and is reducing flow, will not help anything.

You will want to ensure that air flow through the radiator is good, and that air is exiting the under hood area well, possibly achieved by adding a vented hood, or raising the back of the hood. Also your cooling system needs to be in good shape, and working properly.

 

Oh. Thanks for reply man. Well about those two cars I have. After aprox 1300 km I can feel a realy big power loss. I would say about 30% easily.. very weird. I dont know one guy said it might be that as u said bad ventilation and to much air can escape only thru the intake by sucking it into engine. Another said I might using bad engine oil and I def need oil cooler. For those cars all the time was using w15-40. But for my honda I jumped to w5-30. Thx I will try to play with that FITV and IACV. Yeah I heard people just throwing out that egr. I will see. My intake is far away from the engine and yes it has a went near the passenger side headlight. And or course I will buy that heat wrap for exhaust. Forgot to mention that injectors fully working. Previous guy change them to stock factory, ~ 30.000 km ago. Also Yes new oil - petrol filters, bosh better flow fuel pump, cleaned tank. I didnt drive this car yet that far but soon I will. And I hope she would manage to travel hard long distances. I heard f22a series engines are very strong. Thanks again bro. I'm apprciated for reply

 

are you using stock ecu? F20A engine?

It might not "understand" those changes whats been made there and your fuel maps are all wrong now

 

Yea my ecu is stock. engine is f20a5. I'm not professional of honda. A bit new guy. When I got all my small updates as I mentioned ealier I just tookd advice and dissconect battery for 45 mim, then short cables for 15 min, then start car and let it run for 30 min. The car pulls better than stock I can feel also better throttle response for sure. U think I need ecu upgrade or remap?

 

3" is way too big exhaust for F20A engine

 

hah lol okay. When I own this car full exhaust was 2,7 inch so thought okay its prob factory one, lets put 3 inch lol