ysi trim question

[venm4u97]

Just got my ysi trim unit in the mail for my current build.looking to spin the blower as much as I can without having belt slip issues. ...so I plan to run a iw 18% crank pulley and now just wondering how small of a head unit pully to run....not sure what my shift point will be at since my new combo isnt done yet....2.8 or 2.9 inch pulley? ...

Run down on setup

Mmr big bore 314 ci with fox lake stage 3 heads and cams...kooks exhaust...9.5 compression on e 85. Thanks

 

[98 Saleen Cobra]

Sounds like a awesome build man.. Similar to my build.. I would go onto Vortech's calculator and do it to max impellar RPM..

BTW the 18% O/D crank is a great setup but you HAVE to run a electric water pump so keep that in mind..

Make sure you have a 8 rib setup as well.

 

[98 Saleen Cobra]

Alright based on a 7000 shift point here is what I came up with from their site

7.75" crank pulley
7000 rpm shift
2.95" blower pulley
_________
63444 rpm blower speed..

Max RPM of the YSI is 65k, but I know people who spin them to 75k lol.. The main thing with the YSI is that it's such a huge blower it needs to be spun and spun hard.. You can only go so small on pulley combo's before you have to start adding engine RPM.. Big Bore strokes dont' like to spun high from what I've read and talked to to quite a few engine builders.. a stock stroke would have suited you better for turning 7500+rpm.

I wouldn't go much smaller on a blower pulley as you will probably have belt slip.. BUT you never know.

I just did the same specs with a 2.75" pulley and it's 68058rpm.. I have a 2.75" pulley for sale that's a 8 rib if you want.

 

[venm4u97]

Already have the 8 rib set up...was prolly gonna get a aftermarket tensioner as well.....any decent electric water pumps?.....yea sounds like a 2.9 pulley might be what I need

 

[98 Saleen Cobra]

Yep get a ThumpRRR tensioner its what I run..

Meziere electric water pumps is what I've seen on most cars..

 

[MOTOWN M]

I have a YSI with a 15% od IW balancer, and a 2.9 blower pulley which gives 22+ psi , dont bother with a 18% od you wont have clearance for the tensoiner pulley (it will hit the balancer), i run a Thump Tensoiner with a 76mm idler pulley, and it barely clears the balancer!

 

[Lightning&Mach1]

On our Mach we have the 18% od crank with the thumper tensioner and it clears. It's super tight, but it clears. I would highly recommend the Meziere electric water pump also. We have the heavy duty race pump.

Also that max speed rating is how fast they recommend you to spin for the BEARINGS sake. Needless to say we are spinning the crap out of our V2 with a 3.0 blower and 18% od.

 

[MOTOWN M]

On our Mach we have the 18% od crank with the thumper tensioner and it clears. It's super tight, but it clears. I would highly recommend the Meziere electric water pump also. We have the heavy duty race pump.

Also that max speed rating is how fast they recommend you to spin for the BEARINGS sake. Needless to say we are spinning the crap out of our V2 with a 3.0 blower and 18% od.

Dosent the Mach1 use the single bolt tentoiner?:shrug:

 

[Lightning&Mach1]

Dosent the Mach1 use the single bolt tensioner?:shrug:

Yes it does, I didn't know which one you were talking about.

 

[98 Saleen Cobra]

I have a YSI with a 15% od IW balancer, and a 2.9 blower pulley which gives 22+ psi , dont bother with a 18% od you wont have clearance for the tensoiner pulley (it will hit the balancer), i run a Thump Tensoiner with a 76mm idler pulley, and it barely clears the balancer!

This is because you have a 76mm idler, you can get a smaller idler pulley, which is what I recommend.

On our Mach we have the 18% od crank with the thumper tensioner and it clears. It's super tight, but it clears. I would highly recommend the Meziere electric water pump also. We have the heavy duty race pump.

Also that max speed rating is how fast they recommend you to spin for the BEARINGS sake. Needless to say we are spinning the crap out of our V2 with a 3.0 blower and 18% od.

Yes it'll work like I stated above, just get the smaller MM idler when you order.

 

[MOTOWN M]

Yes it does, I didn't know which one you were talking about.

I have the 96-99 front cover which uses a 3 bolt tensoiner, and has better belt wrap around the balancer.

 

[MOTOWN M]

This is because you have a 76mm idler, you can get a smaller idler pulley, which is what I recommend.

I think you misunderstood, i Have a 15% od balancer and my tensoiner fits perfectly, i was saying he would run into problems with a 18% od balancer on a 96-99 front cover which uses a 3 bolt tensoiner, not to mention as stated he will need to run a electric water pump to clear that huge balancer which is going to result in well over 25psi:dw:

 

[98 Saleen Cobra]

I think you misunderstood, i Have a 15% od balancer and my tensoiner fits perfectly, i was saying he would run into problems with a 18% od balancer on a 96-99 front cover which uses a 3 bolt tensoiner, not to mention as stated he will need to run a electric water pump to clear that huge balancer which is going to result in well over 25psi:dw:

No I understood what you were saying, I have the same setup.. Except I don't have a 76mm idler I tried one and it was to close for comfort, I have the stock one which is smaller With the 18% he could use the stock idler pulley which is smaller than a 76mm and should be fine, and he's going to have to run a electric water pump which isn't a bad thing..

He's going to need to run a 18% if he doesn't want slip.. a smaller blower pulley will slip more.. even with a 15%..

You gotta remember every motor is different.. Your combo it might make 25psi but with his Big bore stroker, stg3 heads and cams and huge exhaust it will make less because the motor will be using more of the air and there will be less of a restriction.

 

[MOTOWN M]

No I understood what you were saying, I have the same setup.. Except I don't have a 76mm idler I tried one and it was to close for comfort, I have the stock one which is smaller With the 18% he could use the stock idler pulley which is smaller than a 76mm and should be fine, and he's going to have to run a electric water pump which isn't a bad thing..

He's going to need to run a 18% if he doesn't want slip.. a smaller blower pulley will slip more.. even with a 15%..

You gotta remember every motor is different.. Your combo it might make 25psi but with his Big bore stroker, stg3 heads and cams and huge exhaust it will make less because the motor will be using more of the air and there will be less of a restriction.

I agree about the stroker with ported heads boost not being as hi, but he doesnt need an 18% od balancer to avoid belt slip, i have a Aluminator 10.1 comp motor it came with the single bolt tensoiner cover, i had belt slip up the ying yang, not because of the balancer , but because the single bolt tensoiner has terrible belt wrap that only contacts about 25% of the balancer, i swapped out covers from a 96-99 cobra and as you may know the belt wraps completely around the balancer and eliminates the belt slip issues, if you have a Mach 1 setup which uses the single bolt tensoiner the pulley is nowhere near the balancer anyhow.

 

[98 Saleen Cobra]

Ahh I gotcha.. Yea that makes sense.. I didnt' realize that the single bolt tensioner belt setup was that much difference.. On my setup it wraps around 75% of the crank pulley..

He also has a 97 Cobra so he has the 3 bolt tensioner and the same timing cover as we do

 

[venm4u97]

Thanks for you help guys....so what size with the tensioner pulley?

 

[98 Saleen Cobra]

Stock which is 70mm iirc

 

[venm4u97]

What would u guys do....2.9 or 2.75 pulley with the 18% od

 

[98 Saleen Cobra]

Well how much power are you trying to make lol?? How much do you wanna push your motor and your setup? More power means more wear and tear on shit.. You have EVERYTHING built to handle 8-9xxrwhp?

 

[SVTPete83]

Well how much power are you trying to make lol?? How much do you wanna push your motor and your setup? More power means more wear and tear on shit.. You have EVERYTHING built to handle 8-9xxrwhp?

This...

If you are built to handle some serious power I would still probably go with a 15 and a 2.9. It's still gonna make a crap load of power and u won't have to worry about an electric water pump failing in the middle of a drive.