Transmission spline count?

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Re: Transmission spline count?

Postby Slinky » Fri Apr 24, 2015 12:23 pm

Slinky wrote:
GHOSTOWLGRID wrote:Hey Rettax3, What are your thoughts on this: ... %20%284%29
I kept thinking about turbo's since it was brought up and decided to try and compare a few on the manufacturers web page.
I'm not sure what I am looking at here as far as spooling up time and boost capabilities.
Says T25 inlet and 5 bolt outlet; Sounds right to me but I'm not sure if that is the same as what I have on my current T28 turbo.

If you plan on making over 250-300hp MAX efficiently, than that's a good turbo for you, IMHO that turbo is still a little small and you may choke out the hot side with to much air flow, i would use a turbo with a minimum of 35-45lb/minute, but that's just me.

Thats why I asked, because I'm not sure what to pick. lol
I will look through the listings for a 35-45 lb/minute range turbo.

I suggest this because our engines have enough hp+tq to spin a slightly bigger turbo faster than 4cyl engines, for example 4g63 4cyl engines with a 60lb/min turbo will have full spool at around 4000rpm which is laggy to me, but engines such as the RB series have similar hp+tq as us and will have full spool of a 60lb/min turbo at around 2800rpm,
A basic rule to remember 1lb/min is roughly 10hp

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Re: Transmission spline count?

Postby Beretta1234567 » Fri Apr 24, 2015 12:44 pm

cool. I will follow that.
Last edited by Beretta1234567 on Thu Apr 21, 2016 3:24 pm, edited 1 time in total.

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Re: Transmission spline count?

Postby 3X00-Modified » Fri Apr 24, 2015 1:10 pm

Ok lets get an understanding here... Hydramatic/GM made the 4t60... THEN then made the 4t60e, and both in their lifespan they had a HD variant... Now the reason why I said probably is because I do not know the exact internals of the 4t60 vs the 4t60e. There is a chance that they used some newer parts that are used now in the 4t60e in the 4t60-HD version... In the end that makes it no stronger than a 4t60e-HD, which minus it's HD diff is identical to it's non HD counterpart. That in turn means the trans you have contains the same, or older revisions of parts used in the most hated transmission in these cars. SO you will end up with worn 4th clutch shaft splines, and a worn/broken reverse reaction shell and the poorly designed low roller sprag and the 2nd gear drum that needs to be tig'd to strengthen it and (insert list of items the Gill Younger kit fixes)

My car made just over 300whp last year... and ran a 12.66@108. I was slipping stock clutches 7 years earlier than that and only running a 13.998... If your going to turbo it and increase the size of the turbo you will need to upgrade the internals no questions asked.

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Re: Transmission spline count?

Postby Beretta1234567 » Fri Apr 24, 2015 9:09 pm

I will eventually have it built up.

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