370ci TMS forged iron block
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From: Howell & Fenton MI
370ci TMS forged iron block Just to give you all a heads up i've been out of the game for the last few weeks since my motor took a dump on me 
It basically threw a rod bearing and the only thing that was really salvageable were the heads. With that said I just purchased a new forged TMS 370ci iron block with a new cam...612/612, 236/242, 113+4. I'll be keeping the my PRC 5.3 heads and LS6 intake for now though. Plus I will finally be doing my nitrous now too...a 100 shot for now since i'm still on the stock 10 bolt. Now from what I can tell the 5.3 heads are milled to either a 61cc or 62cc by Texas Speed, and my compression was around 10.8:1 with the old setup. That was also with the GM gasket set. I'm curious with the same gaskets, but new cam and shortblock, what will my new compression be at? Kyle at TMS (hell of a nice guy BTW) seems to think somewhere between 11.1 to 11.8:1, but i'm curious to get other opinions as well. How much more power do you think this setup will produce compared to my old setup? My old setup is still listed in my sig, so let me know what you all think if you will.
It basically threw a rod bearing and the only thing that was really salvageable were the heads. With that said I just purchased a new forged TMS 370ci iron block with a new cam...612/612, 236/242, 113+4. I'll be keeping the my PRC 5.3 heads and LS6 intake for now though. Plus I will finally be doing my nitrous now too...a 100 shot for now since i'm still on the stock 10 bolt. Now from what I can tell the 5.3 heads are milled to either a 61cc or 62cc by Texas Speed, and my compression was around 10.8:1 with the old setup. That was also with the GM gasket set. I'm curious with the same gaskets, but new cam and shortblock, what will my new compression be at? Kyle at TMS (hell of a nice guy BTW) seems to think somewhere between 11.1 to 11.8:1, but i'm curious to get other opinions as well. How much more power do you think this setup will produce compared to my old setup? My old setup is still listed in my sig, so let me know what you all think if you will. Thread Starter
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From: Howell & Fenton MI
Thanks man! Yes old numbers were 405/370, but the previous owner made 460. Both were Dynojet dynos too, so who the hell knows really lol. Regardless of the numbers i'm just curious as to how much more power this setup will produce overall
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Thanks Lemons! Yeah I think you are right on the money about the 460 being too high and my 405 being a bit low, but all i'm caring about is the real world gain that i'll get here. I'm gonna throw it on the same dyno as last time too (where I made the 405) so i'll know where I stand. What will be interesting is how it will respond to the nitrous since it's a larger cubed motor, bigger cam, and more compression
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Yeah I know I hate the added weight part too, but the extra 40hp and added torque should easily make up for it and then some. At this point in time i'm not worried about it. I see a 2000 T/A is your sig with a 370...is that what you have now? Similar to what i'm doing? Just curious...
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Yeah what do they say...something like every 100 lbs is like 10 hp or so. Even if that's not exact i'm sure it's not like 30-40 hp to every 100 lbs lol
Yeah I know I hate the added weight part too, but the extra 40hp and added torque should easily make up for it and then some. At this point in time i'm not worried about it. I see a 2000 T/A is your sig with a 370...is that what you have now? Similar to what i'm doing? Just curious...
Ls3 top end
TSP 231/236 cam (bad choice)
11.9:1 CR
Built for a 300
That setup is gone.. I now just have the 408.
The added weight matters a little more since it is on the front. It will knock off about 15Rwhp of your gains I would bet.
I hated the added weight... I highly recommend getting rid of it where you can. A Kmember is a good idea... After that I would consider buckhart bumper support for the front. That will get a nice chunk of weight gone that you added on the front.
https://ls1tech.com/forums/drag-raci...-supports.html
62cc w/MLS gaskets and Piston Out of the Hole .005" (Kyle told me that's what they avg) is 11.28:1.
61cc is 11.42.
I'm debating on whether or not I want to pull the trigger for the 6L block. You get 20cid more and more bore, but you also gain 100lbs. Either way, it should make 10HP more and that would be enough to overcome the weight penalty in a straight line. The added weight to the front just means you need stiffer springs and stiffer front swaybars to balance it out.
61cc is 11.42.
I'm debating on whether or not I want to pull the trigger for the 6L block. You get 20cid more and more bore, but you also gain 100lbs. Either way, it should make 10HP more and that would be enough to overcome the weight penalty in a straight line. The added weight to the front just means you need stiffer springs and stiffer front swaybars to balance it out.
62cc w/MLS gaskets and Piston Out of the Hole .005" (Kyle told me that's what they avg) is 11.28:1.
61cc is 11.42.
I'm debating on whether or not I want to pull the trigger for the 6L block. You get 20cid more and more bore, but you also gain 100lbs. Either way, it should make 10HP more and that would be enough to overcome the weight penalty in a straight line. The added weight to the front just means you need stiffer springs and stiffer front swaybars to balance it out.
61cc is 11.42.
I'm debating on whether or not I want to pull the trigger for the 6L block. You get 20cid more and more bore, but you also gain 100lbs. Either way, it should make 10HP more and that would be enough to overcome the weight penalty in a straight line. The added weight to the front just means you need stiffer springs and stiffer front swaybars to balance it out.
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From: Howell & Fenton MI
Thanks Senical, I might look into that when I recoup some money lol
Jake, from what Kyle at TMS has said the biggest thing that you will gain is torque with all else being equal.
Would you agree with that Lemons?
Jake, from what Kyle at TMS has said the biggest thing that you will gain is torque with all else being equal.
Would you agree with that Lemons?
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From: Howell & Fenton MI
Okay, I just got the new TMS 370 shortblock and it looks great, but I have a question for all you experts out there. I'm told that it's not a good idea to even start the car once it's all back together before some type of base tune, because it could wash the rings and they may never seal right after that. I was told the best way to go about all this is to have it towed to my tuner (prior to even starting the car) have him download a base tune first, then start it and let it run for a few minutes, then change the oil, then finally have a full on tune put in. Does this sound right? I mean how necessary is this? Now mind you the car had a dyno tune previously. My concern is that I have it towed to my tuner (and hour away mind you) then come to find out that the car my not even start for whatever reason...then i'm kind of screwed right lol? So now if it does start I then have my tuner change the oil, and then do a all out performance tune lol. This sounds like a total pita lol So lets hear it guys
Lemons, what did you do?
So lets hear it guysLemons, what did you do?