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The mkiv Supra Owners Club

NA engines, who's in the know ???


Suprash

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Looking for a contact who knows the NA engine in the Supes. Have various questions that need answering related to the NA, and will have more in the future no doubt.

 

Could someone step forward that could offer advice/answer questions..........

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I have but people dont seem to answer them, I have already asked what torque a standard NA clutch can hold, also we need someone that works on these engines and knows. We have some queries reagrding some of the breathers, and I dont need people guessing, or asuming, I need someone I can ask directly for a eduacted answer, and not to be discussed with no final outcome.........which tends to happen on here ;)

 

Do you know alot about them then mate :conf:

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I think the problem is that theres not many people who actually get their NA tuned as the cost and complexity outweighs changing to a twin turbo.

 

Its basically a 3l NA engine which is the same as in the Lexus GS300 I believe, so Lexus Owners Club might be a useful port of call.

 

As its a non-turbo then pretty much all the usual NA tuning applies, flowing the head, improved breathing etc.

 

Would be interesting to see what you can find out.

 

JB

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Well were really going to town on the NA, so might have some usefull stuff.

 

Were pretty much going through all the breathing system on teh NA to find out whats needed and whats not (ie, used for cleaner emissions and stuff).

 

What we did notice is that the NA has a engine water feed onto the throttle body, is this used for frost purposes or other reasons as it seems it could be heating the air intake charge, if its not needed then it may be able to be blanked therefor giving colder air intake temps.

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I have logged on Supraforums under my ID, except I cant do anyting like post or PM, and I cant re-register as the cookies are picking me up. I cant see anyway of contacting the mods to get them to have a look at my account. Branners, whats the best way to sort this.....

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Originally posted by Ashley Willis

I have logged on Supraforums under my ID, except I cant do anyting like post or PM, and I cant re-register as the cookies are picking me up. I cant see anyway of contacting the mods to get them to have a look at my account. Branners, whats the best way to sort this.....

 

2 things, depends how long its been but they did require you to ask for a password reset at one point so get a password reset done and sent out to you. Other thing to check is that you arent blocking cookies from Supraforums as thats what allows people to register on here but not when it keeps asking them to log back in.

 

If that fails let me know and I will see what I can sort out with them.

 

JB

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Well it seems you can remove the coolant feed through the throttle body to reduce air intake temps, but you then risk loosing the cars ability to cold start, that all depends on how cold it gets where the car is located, for the US and Oz its probably not much of a problem, but I will still run this mod and see what happens in the winter.

 

I can search now after re-activating my account, but I still cant post, it said something about waiting 24hrs, would that be a similar process that we run on this board, ie, maybe not able to post until some sort of verification from a MOD or someone.....????

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hmm, strange, not seen the 24 hours thing before, but yes, its probably waiting for moderator verification.

 

I think Lust2luv currently has the fastest NA mkiv in the UK, at TOTB1 it was putting in similar times to a stock mkiv UK spec TT. Im sure theres more to come from an NA, just the cost keeps people from doing too much.

 

JB

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Originally posted by Ashley Willis

Well it seems you can remove the coolant feed through the throttle body to reduce air intake temps, but you then risk loosing the cars ability to cold start, that all depends on how cold it gets where the car is located, for the US and Oz its probably not much of a problem, but I will still run this mod and see what happens in the winter.

 

 

how about fitting an isolation valve in the feed line? that way when the weather is really cold you can just turn the tap on. or if you really wanted to be flash an in line solenoid wired to a switch in the car

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Originally posted by leett

how about fitting an isolation valve in the feed line? that way when the weather is really cold you can just turn the tap on. or if you really wanted to be flash an in line solenoid wired to a switch in the car

 

mmmmmmm, now we are getting fancy ;) :D

 

Good idea Lee, I like it........

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See Ash,

 

Getting a few decent pointers now mate. :) Fair play I know wht you mean about wafflein threads when all you want is good technical advice. I do not have a NA but I suppose all standard NA tuning applies here.

 

Air Intake (cold air feed where possible or shielded from heat as a minmum)

Properly sized free flowing exhaust manifold

Cat removal

Correctly sized exhaust system

Gas flowed cylinder head

Possibly larger valves depending on goals

Close attention to porting around valve throat and seat

Polished combustion chambers

Inlet manifold tidied up (depending on how rough it is internally)

Removal of manifold heating

Camshafts (again depends on outright goals but on a 3litre motor you can afford to go fairly wild without a huge trade off in low speed torque)

Lightened and fully balanced internals, pulley and flywheel assembly

Prorammable ecu (Motec, DTA, or similar)

 

Has anyone ever ran the NA on throttle bodies, any idea if there's any gains over the plenum chamber setup with its fancy runner length assembly. I would have thought that on anything less than an all out race engine the "stock based" runners and plenum would be sufficient.

 

Not sure on the safe rev limit of the bottom end, may be worth having a word with CW. I'd imagine no more than 7500 max without turning attention to the rods and bolts at least. I have no idea what sort of revs/power the stock pistons are safe to but this all depends if you're heading towards high rpm tuning.

Big £££'s if that's the case.

 

 

Dan

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Originally posted by Ashley Willis

What we did notice is that the NA has a engine water feed onto the throttle body, is this used for frost purposes or other reasons as it seems it could be heating the air intake charge, if its not needed then it may be able to be blanked therefor giving colder air intake temps.

 

 

100% correct, the NA does have one, and it is a common and easy 'mod' to do. Go for it! It is all on SF, so sign up again and sort out your account, a few seraches on there will bring up all you need. :)

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Originally posted by dandan

Not sure on the safe rev limit of the bottom end, may be worth having a word with CW. I'd imagine no more than 7500 max without turning attention to the rods and bolts at least. I have no idea what sort of revs/power the stock pistons are safe to but this all depends if you're heading towards high rpm tuning.

Big £££'s if that's the case.

 

 

Dan

 

Same goes for the top end. You'll probably end up needing different valve springs at least to stop you running into float.

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  • 2 years later...
Well it seems you can remove the coolant feed through the throttle body to reduce air intake temps, but you then risk loosing the cars ability to cold start

 

i was thinking of doing this mod myself .i wonder how cold it needs to be before you get starting probs as we know toyota is good at over engineering and we might not need it in our winters P.M me pls and let me know if you had any probs-- thanks bud

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how about fitting an isolation valve in the feed line? that way when the weather is really cold you can just turn the tap on. or if you really wanted to be flash an in line solenoid wired to a switch in the car

what a good idea well done mate wonder where i can get a valve that will fit such a small tube??

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i was thinking of doing this mod myself .i wonder how cold it needs to be before you get starting probs as we know toyota is good at over engineering and we might not need it in our winters P.M me pls and let me know if you had any probs-- thanks bud

 

Never done it in the end dude, me and the misses split, it was hers and then it was written off a few months later anyway.... ;)

 

Cant beleive this thread has been re-dug up, 2004 as well...... :D

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