Valve Springs and shift points

[MR2turbo93]

alright hears the situtation...

I have a Stock MR2 turbo ... well its has suspension work but no power adders. When i get on it ... (cough, race , cough) it feels like i pulls harder and goes faster if i shift a 6500rpm rather than 5500rpm as suggested elsewhere in these forums. My tires are 255/40/17 in the back and 225/45/17 in the front. Idk if that has something to do with it but I was looking for imput.

One of my friends said that I might have valve float above 6000 rpm and that why it doesnt pull hard. I explained to him how the CT26 isnt as good a high rpms. Bottom line its not valve float. I still wanted to upgrade my head to rev a little higher....(i'm not looking to drag race i like doing timetrials that what my car is getting setup for) I want to get the HKS valve springs and the MR-S shimless bucket conversion. I was wondering how high i'll be abled to go relieably. And how this would affect my power curve.

I currently have these parts waiting to go on i just need to get my car checked out to make sure its good enough to be beefed up....(17psi is my goal)
-tanabe DP(on its way)
-Blitz Nur Spec Exhaust(on its way)
-Greddy Intercooler
-Fans for engine lid (installed)
-Turbo XS 2 stage boost controller
-Apex-i S-AFC
-CT20B (buying in about a month)

Idk if this will effect how high i can go but any imput would be nice....thanks

[JekylandHyde]

You really need a dyno plot of your car to locate the ideal shift points. See the sticky in the drag racing forum on mr2oc.com for the math on figuring out your shift points.

Revving higher with the CT26 would be pointless since it can't carry boost till redline. I see you mentioned getting a CT20B ... that will definitely help you pull till redline.

I did not see your mileage, but I am over 200,000 miles and I am now revving to 7500 and occassional spikes to 8,000 and I am on a 100% stock, original head except for new, long-duration staggered cams.

[MR2turbo93]

I'm just under 140,000 so i need to get everything checked out to make sure my motor is good enough to handel the new parts. i'm not sure if the motor was abused before i bought it a year ago so i want to do the normal stuff, leakdown test, compression test, full fluid change... the whole 9 yards. I noted that you said you have new cams now... what do you shift at now?
And i was wondering if the springs could be worn easily.... or rater if when going to 7500 you'd notice if there werent closing?

Thanks for the info, the forums have been a big help for me on choosing which parts to buy for my style of driving.

[MR2turbo93]

Oh one more question .... what the best coolant for a MR2? ( i dont drive in the winter (December to late March-early April))

[JekylandHyde]

I use the factory coolant.

[MR2turbo93]

do you get it from the toyota dealership or from autozone and use what it says in the manual?